Bee Health: The Role of Pesticides

Congressional research reportFeb 17, 2015

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R43900

Bee Health: The Role of Pesticides

Summary

Over the past few decades there has been heightened concern about the plight of honey bees as

well as other bee species. Given the importance of honey bees and other bee species to food

production, many have expressed concern about whether a “pollinator crisis” has been occurring

in recent decades. Although honey bee colony losses due to bee pests, parasites, pathogens, and

disease are not uncommon, there is the perception that bee health has been declining more rapidly

than in prior years, both in the United States and globally. This situation gained increased

attention in 2006 as some commercial beekeepers began reporting sharp declines in their honey

bee colonies. Because of the severity and unusual circumstances of these colony declines,

scientists named this phenomenon colony collapse disorder (CCD). Since then, honey bee

colonies have continued to dwindle each year, for reasons not solely attributable to CCD. The

U.S. Department of Agriculture (USDA) reports that CCD may not be the only or even the major

cause of bee colony losses in recent years. In the United States, USDA estimates of overwinter

colony losses from all causes have averaged nearly 30% annually since 2006.

The precise reasons for honey bee losses are not yet known. USDA and most scientists working

on the subject seem to agree that no research conclusively points to one single cause for the large

number of honey bee deaths. This general conclusion was reconfirmed in a 2013 joint report by

USDA and the U.S. Environmental Protection Agency (EPA). Reasons cited for bee declines

include a wide range of possible factors thought to be negatively affecting pollinator species.

However, one issue widely noted is the role that pesticides—in particular, neonicotinoid

pesticides—might play in overall bee health. Pesticides are the focus of this report. Pesticides are

among many identified factors known to affect bee health, including pests and diseases, diet and

nutrition, genetics, habitat loss and other environmental stressors, and beekeeping management

issues, as well as the possibility that bees are being negatively affected by cumulative, multiple

exposures and/or the interactive effects of several of these factors.

The focus of this report on bee exposure to pesticides is not intended to imply that pesticides are

any more important in influencing the health and wellness of bees than other identified factors

influencing bee health. Pesticides are one of many influences on bee health. The current state of

knowledge on pesticides and bee health is summarized in the USDA-EPA report:

it is not clear, based on current research, whether pesticide exposure is a major factor associated

with U.S. honey bee health declines in general, or specifically affects production of honey or

delivery of pollination services. It is clear, however, that in some instances honey bee colonies

can be severely harmed by exposure to high doses of insecticides when these compounds are

used on crops, or via drift onto flowers in areas adjacent to crops that are attractive to bees.

Some experts emphasize research supporting the hypothesis that “total pesticide load” is an

important influence on honey bee health, probably in combination with mite infestation, poor

nutrition, viruses, and perhaps other stressors.

The past two farm bills (P.L. 110-246, P.L. 113-79) provided for increased funding for bee

research, among other types of support to protect pollinators. Other bills in the 113th Congress

addressed pesticide issues more directly. H.R. 2692 would have suspended registrations of

neonicotinoids and banned new registrations of any pesticide in some cases. Another bill, H.R.

5447, would have amended U.S. pesticide laws to expedite the review and approval of products to

control “parasitic pests” in managed commercial bee colonies, and would have required USDA

and EPA to evaluate threats to pollinators and the availability of pesticides to manage bee pests.

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Contents

Background and Introduction .......................................................................................................... 1

U.S. Pesticide Laws and Regulation ................................................................................................ 4

Pesticide Laws and Statutory Framework ................................................................................. 4

Pesticide Registration Process ................................................................................................... 5

Neonicotinoid Pesticides ........................................................................................................... 6

Possible Role of Pesticides in Bee Health ....................................................................................... 8

Best Management Practices to Protect Pollinators ........................................................................ 11

Federal Agency Efforts .................................................................................................................. 15

National Pollinator Health Strategy (“Presidential Memorandum”) ....................................... 15

USDA-EPA Joint Report ......................................................................................................... 16

Environmental Protection Agency ........................................................................................... 17

EPA’s Pesticide Registration Review of Neonicotinoid Pesticides ................................... 17

EPA’s Consideration to Modify Thiamethoxam Tolerance Levels .................................... 19

EPA’s New “Bee Advisory” Labeling Requirements ........................................................ 20

EPA Support of State Pollinator Protection Plans ............................................................. 23

EPA Development of Voluntary Controls for Pesticide Drift ............................................ 23

Fish and Wildlife Service Memorandum ................................................................................. 24

Other Ongoing Efforts ................................................................................................................... 24

Restrictions in Some U.S. Cities and Counties ....................................................................... 24

Restrictions in the European Union ......................................................................................... 25

Restrictions in Canada ............................................................................................................. 27

Legal and Other Actions by Some Interest Groups ....................................................................... 28

Selected Actions by Environmental Groups ............................................................................ 28

Selected Actions by Agrochemical Companies ....................................................................... 30

Congressional Consideration ......................................................................................................... 31

Saving America’s Pollinators Act ............................................................................................ 32

Expedited Pesticide Registration for Managing Parasitic Pests .............................................. 33

Figures

Figure 1. Stress Factors in Honey Bee Populations ......................................................................... 3

Figure 2. Major Routes of Exposure of Foraging Bees to Pesticides ............................................ 10

Figure 3. EPA’s Bee Advisory Box ................................................................................................ 20

Figure 4. Pollinator Stewardship Council’s Analysis of EPA’s Bee Advisory Box ....................... 21

Tables

Table 1. Schedule for EPA Review of Neonicotinoid Pesticides ................................................... 17

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Appendixes

Appendix. Review of the Scientific Literature .............................................................................. 35

Contacts

Author Contact Information........................................................................................................... 43

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here is increasing concern both in the United States and globally about whether a

“pollinator crisis” has been occurring in recent decades. Reports worldwide indicate that

populations of managed honey bees, wild bees, and native bees have been declining, with

colony losses in some cases described as severe or unusual.1 Other reports indicate that many

insect pollinator species may be becoming rarer, which some say may be a sign of an overall

global biodiversity decline.2

Many reasons are cited for bee population declines, including bee pests and diseases, diet and

nutrition, genetics, habitat loss, agricultural pesticides, and beekeeping management. Because

pesticides have been the focus of concerns in Europe and in the United States, this CRS report

briefly describes recent scientific research and analysis regarding the potential role of pesticides

among the factors affecting the health and well-being of bees. The report concludes with a

summary of recent regulatory activity regarding neonicotinoids, a type of pesticide, and also

provides the statutory authority and regulatory activities related to pesticide use at the U.S.

Environmental Protection Agency (EPA), the federal agency charged with assessing risks and

regulating U.S. sale and use of pesticides.

The focus of this report on bee exposure to pesticides is not intended to imply that pesticides are

any more or less important in influencing the health and wellness of bees than any of the other

identified factors influencing bee health.

Background and Introduction

In the United States, honey bee colony losses due to bee pests, parasites, pathogens, and disease

are not uncommon. However, in late 2006, concerns about honey bees gained heightened

attention when commercial beekeepers along the East Coast began reporting sharp declines in

their bee colonies. Because of the severity and unusual circumstances of these colony declines,

scientists named this phenomenon colony collapse disorder (CCD). This issue was legislatively

active in the 110th Congress and resulted in increased funding for honey bee research, among

other types of farm program support to protect pollinators, as part of the 2008 farm bill (Food,

Conservation, and Energy Act of 2008, P.L. 110-246). The 2014 farm bill (P.L. 113-79)

reauthorized and expanded upon many of these provisions.3

The U.S. Department of Agriculture (USDA) reports that U.S. beekeepers continue to lose

colonies each year. Since 2006, USDA estimates that overwinter4 bee colony losses have

averaged nearly 30% annually.5 However, USDA reports that in 2012/2013, “there were more

colonies that dwindled away” rather than suffering from CCD, which is characterized by a sudden

loss in bee colony populations and the absence of dead bees.6 USDA also claims that “beekeepers

More information on the difference between managed honey bees and native bees is available in CRS Report R43191,

Bee Health: Background and Issues for Congress.

United Nations Environment Programme (UNEP), Global Honey Bee Colony Disorders and Other Threats to Insect

Pollinators, UNEP Emerging Issues, 2010.

For more information, see CRS Report R43191, Bee Health: Background and Issues for Congress.

Bee colony losses are common during the winter months, especially in colder climates. Hives should be strong and

healthy before going into winter in order to minimize losses.

D. vanEngelsdorp, et al., “Colony Loss 2013-2014,” May 15, 2014, http://beeinformed.org/.

K. Kaplan, “Fact Sheet: Survey of Bee Losses During Winter of 2012/2013,” http://www.ars.usda.gov/is/br/beelosses/

(continued...)

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did not report CCD as a major cause of colony loss” for overwinter losses reported in its 20122013 and 2011-2012 surveys. These data are tracked for managed honey bees only.

Comparable data and information is not collected available for native or wild bee species. Such

data collection is complicated by sheer number and solitary nature of native and wild bee species.

Managed Honey Bees and Wild Bee Species

Honey Bees

Honey bees (Apis mellifera; Family: Apidae) are the most well-known bee species. However, honey bees are only one

of the world’s estimated 17,000 described bee species, and one of the estimated total of 20,000 to 30,000 bee

species worldwide. Honey bees are not native to North America, but were introduced by European settlers in the

1600s. Honey bees are considered to be “social” bees in that they have a single egg-laying queen and sterile worker

bees that tend to work together in a highly structured social order, consisting of cooperation and division of labor

within a colony, as well as the presence of two generations in a single nest at the same time. Social behavior allows

bees to be domesticated and managed.

Some types of native bees may also be managed, such as bumble bees, orchard bees, and alfalfa leaf-cutting bees.

Some of these bees (such as bumble bees and some types of stingless bees) exhibit some of the social behaviors

commonly associated with honey bees. Some bumble bee species are managed in controlled environments to

pollinate greenhouse tomatoes.

Wild Bee Species

An estimated 4,000 species of bees are native to North America. With few exceptions, most of these are wild and

not managed. The five most common families of native bees in North America are Andrenidae, Apidae, Colletidae,

Halictidae, and Megachilidae. Andrenid bees are all ground nesters, and mostly comprise a large family of dark,

nondescript bees, although some are colorful. Bees in the large Apidae family include not only honey bees, but also

bumble bees (such as Bombus spp.), carpenter bees, squash or gourd bees, and others. Most types of wild bees are

“solitary” bees and do not have long-lived colonies. About 70% of native bee species are solitary ground nesting

bees, and about 30% are solitary wood nesting bees. About 45 species of native bees in the United States are social

bumble bees. Compared to most native species, bumble bees (Bombus) are better studied and, as noted by USDA,

among the most effective crop pollinators.

For more information, see: CRS Report R43191, Bee Health: Background and Issues for Congress.

To date, the precise reasons for honey bee colony losses are still unknown. USDA and most

scientists working on the subject seem to agree that none of the research conclusively points to

one single cause for the large-scale number of honey bee deaths. This general conclusion was

reconfirmed in a May 2013 report by USDA and the U.S. Environmental Protection Agency

(EPA), National Stakeholders Conference on Honey Bee Health (commonly referred to as the

“USDA-EPA joint report”).7 A 2007 study by the National Research Council (NRC) of the

National Academy of Sciences, Status of Pollinators in North America (referred to here as the

2007 NRC study), also provides a detailed scientific context for bee health. A series of other

(...continued)

index.htm. Whether losses may be attributable to CCD may be based, in part, on reported colony losses “with no dead

bees present, which is indicative of CCD.” See USDA, CCD Progress Report, June 2012, p. 9.

USDA, Report on the National Stakeholders Conference on Honey Bee Health, National Honey Bee Health

Stakeholder Conference Steering Committee, May 2013, http://www.usda.gov/documents/ReportHoneyBeeHealth.pdf.

This document, widely referred to as the USDA-EPA joint report, provides proceedings of an October 2012 workshop

convened by USDA and EPA (edited by the National Honey Bee Health Stakeholder Conference Steering Committee).

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reports documenting the findings of USDA’s ongoing research also describes the many factors

affecting honey bees.8 See Figure 1.

Figure 1. Stress Factors in Honey Bee Populations

Source: OPERA Bee Health in Europe, 2013, http://www.operaresearch.eu/.

Reasons cited for bee population declines include a wide range of possible factors. Potential

identified causes include bee pests and diseases, diet and nutrition, genetics, habitat loss and other

environmental stressors, agricultural pesticides, and beekeeping management issues, as well as

the possibility that bees are being harmed by cumulative, multiple exposures and/or the

interactive effects of each of these factors.

One issue widely reported in the media is the potential role that pesticides—in particular,

neonicotinoid pesticides—might play in overall bee health. As one of the potential causes of

honey bee colony declines, this report addresses what role, if any, pesticides play in influencing

the health and wellness of bees. Regarding honey bee health, the current state of knowledge of

pesticides was summarized in a 2013 report by USDA and EPA:9

See, for example, USDA’s annual CCD Research Progress Reports, available at http://www.ars.usda.gov/News/

docs.htm?docid=15572.

USDA-EPA joint report, p. 16. Attributed to conferees Reed Johnson (Ohio State University) and James Frazier

(Pennsylvania State University). The report references consensus by the Pesticide Risk Assessment for Pollinators in a

2011 Executive Summary, published by the Society of Environmental Toxicology and Chemistry (SETAC).

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There is broad consensus among all stakeholders that pesticide use should not affect honey

bees in such a way that (1) honey production is reduced or (2) pollination services provided

by bees are threatened.... However, it is not clear, based on current research, whether

pesticide exposure is a major factor associated with U.S. honey bee health declines in

general, or specifically affects production of honey or delivery of pollination services. It is

clear, however, that in some instances honey bee colonies can be severely harmed by

exposure to high doses of insecticides when these compounds are used on crops, or via drift

onto flowers in areas adjacent to crops that are attractive to bees.

This report examines in greater detail the role of pesticides, providing a summary of selected

scientific literature. The relative importance of pesticides in U.S. or global bee health is a subject

of numerous research projects, some of which are discussed in this report.

Some groups have expressed concern about the assessment of most experts that the causes of

pollinator health concerns are multifaceted and may involve the interaction of multiple factors,

since this may deflect attention from the potential role of exposure to pesticides. On the other

hand, some groups appear unwilling to acknowledge that pesticide exposure may play an

important role in pollinator health concerns, especially if this acknowledgment leads to

restrictions or reductions in the use of certain pesticides or related crop pest controls.

This report provides information regarding the potential role of pesticides in the health of bee

colonies, and also the importance of pesticides relative to other influences on bee health. The

report provides general information about the nature of pesticides, pesticide uses, and pesticide

regulation in the United States, as well as more specific information about the registration status

of a class of pesticides known as neonicotinoids, which have been implicated in some studies

concerning honey bee colony declines. This report also describes a range of options to address

pesticide exposure by bees, including implementing crop- and/or product-specific best

management practices (BMPs) regarding pesticide use and applications. Some U.S. cities as well

as some other countries, including Canada and those in Europe, have opted to institute restrictions

on the use of certain pesticides. Congress has introduced similar legislation, but has also

considered alternative policy options to address this issue.

U.S. Pesticide Laws and Regulation

Pesticide Laws and Statutory Framework

Pesticides are broadly defined in U.S. law as chemicals and other products used to kill, repel, or

control pests.10 Familiar examples include pesticides used to kill insects (insecticides) and weeds

(herbicides) that can reduce the yield, and sometimes harm the quality, of agricultural crops,

ornamental plants, forests, and pastures, or wooden structures (e.g., through termite damage). But

the broad legal definition of “pesticide” also applies to products with less familiar “pesticidal

uses.” For example, substances are pesticides when used to control mites, mold, mildew, and

other nuisance growths in hives or on equipment. The term also applies to disinfectants and

sterilizing agents, animal repellents, rat poison, and many other substances. An estimated 18,000

pesticide products are currently in use in the United States.11 Pesticides vary greatly in toxicity,

FIFRA § 2(u). 7 U.S.C. 136-136y. See also CRS Report RL31921, Pesticide Law: A Summary of the Statutes.

S. Kaiser, EPA, personal communication with CRS staff, December 16, 2011.

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persistence in the environment, and ability to bioaccumulate up the food chain, as well as in the

range of plants and animals that are likely to be affected in the event of exposure. Some are nearly

nontoxic to some species but exquisitely toxic to other species.

All pesticides are regulated by EPA under the authority of the Federal Insecticide, Fungicide, and

Rodenticide Act (FIFRA),12 and approximately 5,800 pesticide products used in food production

also are regulated under the Federal Food, Drug, and Cosmetic Act (FFDCA).13 FIFRA requires

EPA to regulate the sale and use of pesticides in the United States through product registration

and labeling so as to prevent unreasonable adverse effects on people and the environment, taking

into account the costs and benefits of various pesticide uses. FIFRA prohibits the sale of any

pesticide in the United States unless it is registered (licensed) and labeled to indicate approved

uses and restrictions. It is a violation of the law to use a pesticide in a manner that is inconsistent

with the label instructions. EPA registers each pesticide product for each approved use. For

example, a product may be registered for use on bee hives to control mites or as a seed treatment

for corn.14 In addition, FIFRA requires EPA to reregister pesticides first registered prior to 1984

and to review all registered pesticides periodically on a 15-year cycle, based on new data that

meet current regulatory and scientific standards.

For the 600 or more active ingredients in pesticide products that are registered for use in food

production, Section 408 of the FFDCA authorizes EPA to establish maximum allowable residue

levels (also known as “tolerances”) to ensure that human exposure to the pesticide ingredients in

food and animal feed will be “safe.” A “safe” tolerance is defined in the law as a level at which

there is “a reasonable certainty of no harm” from the exposure, even when considering total

cumulative and aggregate pesticide exposure of children. Under the FFDCA, foods (or animal

feeds) with a residue of a pesticide ingredient for which there is no tolerance established, or with

a residue level exceeding an established tolerance limit, are declared “unsafe” and “adulterated”;

such foods cannot be sold in interstate commerce or imported to the United States. Pesticides may

not be registered under FIFRA for use on food crops unless tolerances (or exemptions) have been

established under the FFDCA.15

Pesticide Registration Process

When pesticide manufacturers apply to register an active ingredient for a pesticide, a commercial

pesticide product, or a new use of a pesticide registered under FIFRA Section 3, EPA requires

them to submit scientific data on toxicity and behavior in the environment. In evaluating a

pesticide registration application, EPA assesses a range of potential human health and

environmental effects associated with use of the product. EPA’s process of registering a pesticide

comprises a scientific, legal, and administrative procedure involving the ingredients of the

pesticide; the particular site or crop where it is to be used; the amount, frequency, and timing of

its use; and storage and disposal practices.16 EPA may require data from any combination of more

7 U.S.C. §136 et seq.

21 U.S.C. §§ 301, et seq.

The Federal Seed Act (7 U.S.C. § 1561) defines a treated seed as any seed “given an application of a substance or

subjected to a process designated to reduce, control, or repel disease organisms or other pests, which attack seeds or

seedlings growing therefrom.”

For more information, see CRS Report RL31921, Pesticide Law: A Summary of the Statutes; and CRS Report 96759, Pesticide Legislation: Food Quality Protection Act of 1996 (P.L. 104-170).

EPA, “About Pesticide Registration,” http://www2.epa.gov/pesticide-registration/about-pesticide-registration. Other

(continued...)

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than 100 different tests, depending on the potential toxicity of active and inert ingredients and

degree of exposure.

To register a pesticide for use on food, EPA also requires applicants to determine the amount of

residue that could remain on crops, as well as on (or in) food products (such as corn syrup),

assuming that the pesticide product is applied according to the manufacturers’ recommended rates

and methods. Based on the data submitted, EPA determines whether and under what conditions a

proposed pesticide use would present an unreasonable risk to human health or the environment,

and, for a food or residential use, whether its use would be safe. Some features of pesticides that

might affect registration decisions include the specificity of the pesticide for the targeted pest, its

toxicity to people who apply it, its tendency to persist in the environment over time, and its ability

to bioaccumulate in animals higher in the food chain.

EPA specifically takes into account unintended harm to bees and available information for other

nontargeted insects in its registration decisions. EPA requires studies to determine acute (shortterm) toxicity of a pesticide on individual bees when they come into body contact with pesticide

residue. EPA also collects reports on bee-kill incidents. If a pesticide appears to be very toxic to

bees, EPA may require long-term studies of its effects.

If the risk is determined to be unreasonable or unsafe, EPA attempts to mitigate the risk by

adjusting requirements on the label (for example, requiring a buffer zone around lakes and

streams or requiring personal protective equipment for pesticide handlers). If the risk remains

unreasonable or unsafe, EPA will refuse to register the pesticide. If the risk is determined to be

reasonable and safe, registration is granted, and the agency specifies the approved uses and

conditions of use, including safe methods of pesticide storage and disposal, which the registrant

must explain on the product label. EPA can and often does require specific application methods to

be printed on the product label to minimize environmental damage. For example, the label

sometimes requires that application of certain pesticides occur only when bees are not foraging,

when there is little wind, or in a granular form or as a seed coating rather than aerially, in order to

minimize spray drift off property. Pesticide registrations are reviewed at least once every 15 years

to consider new scientific information and may be reviewed at any time in response to reports of

adverse effects and possible unreasonable risks from use of particular pesticides.

Neonicotinoid Pesticides

Neonicotinoids are a relatively new major class of insecticides and among the fastest-growing

class of insecticides in modern crop protection. Developed in the 1980s, some products such as

imidacloprid were first introduced in the early to mid-1990s, but not widely marketed until the

mid-2000s. Neonicotinoids are systemic pesticides that, regardless of application method (spray,

drip irrigation, granular spreading, or seed coating), once taken into the plant, migrate into all

parts, including flowers, pollen, and nectar.17 Neonicotinoids are related to nicotine and were

developed as an alternative to highly toxic (to humans) organophosphate insecticides such as

methyl parathion.18 Active ingredients of some of the most commonly applied neonicotinoids

(...continued)

information is available at CRS Report RL32218, Pesticide Registration and Tolerance Fees: An Overview.

UNEP, Global Honey Bee Colony Disorders and Other Threats to Insect Pollinators, 2010.

S. P. Bradbury, Office of Pesticide Programs, letter to Peter T. Jenkins, Center for Food Safety and International

Center for Technology Assessment, July 17, 2012.

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include imidacloprid, clothianidin, and thiamethoxam. Others include acetamiprid, dinotefuran,

nitenpyram, and thiacloprid. (See text box below.)

Neonicotinoid Insecticides

In the United States, neonicotinoid pesticides are available for use in about 140 crops and garden/horticultural

products, and provide potent and systemic action for crop protection, particularly from pests in soil and sap-sucking

pests. They are used for seed treatment on most corn, soybeans, canola, sunflower, cereal grains, sugar beets, and

potatoes. They are also used as foliar sprays on field and many fruit and vegetable crops (such as apples, cherries,

peaches, oranges, berries, leafy greens, tomatoes, and potatoes) and are applied to cereal grains, rice, nuts, and wine

grapes. They may also be injected into tree roots or stems and sprayed on tree bark to protect against pests. A

single application can provide protection for several months or years and may remain with the plant as it grows.

Since these types of pesticides can persist in soil or plants for long periods of time, this raises the potential that bee

exposure will persist, even at low levels.

Neonicotinoids reportedly accounted for almost 25% of the global pesticide market, and imidacloprid was the largest

selling insecticide in the world in 2009, with sales exceeding $1 billion. More recent information suggests that the

total global market for neonicotinoid pesticides exceeded $2.6 billion in 2011.

Neonicotinoid Active Ingredients:

•

Acetamiprid

•

Clothianidin

•

Dinotefuran

•

Imidacloprid

•

Nitenpyram

•

Thiocloprid

•

Thiamethoxam

Major Trade Names: Admire®, Acceleron®, Axcess®, Attendant®, Belay®, Cruiser®, Gaucho®, Nitro Shield®,

Poncho®, and Trimax Pro®.

Selected Home and Garden Products: ALOFT®, ARENA®, Criterion™, DIY Tree Care Products, Fertilome®, Flagship™, Green Light®, Safari®, Hi-Yield®, Knockout Ready-to-Use products, Mallet®, Marathon®,

Maxide®, Meridian®, Merit®, Monterey Once A Year products, Ortho®, Safari products, Surrender®, Transtect™,

Xytect™, and Zylam®, and also several Bayer Advanced and Bayer Environmental Science products (including “12Month”; “2-in-1”; “All-in-One”; “Complete Brand”; “Dual Action”; “Hunter”; “Lesco Bandit”; “Season-Long”;

termite; and Bayer’s fruit, citrus, and vegetable products).

Major Manufacturers: Bayer Advanced, Syngenta Crop Protection, LLC, and The Scotts Company, as well as

ArborSystems, Arysta LifeScience, Control Solutions, Inc., Gro Tec, Inc., Gulfstream Home and Garden, Lawn and

Garden Products, Inc., Nufarm Americas Inc., OHP, Inc., Rainbow Treecare Scientific Advancements, Valent U.S.A.

Corporation, and Voluntary Purchasing Groups, Inc.

Sources: P. Jeschke1 and R. Nauen, “Neonicotinoids—from Zero to Hero in Insecticide Chemistry,” Pest

Management Science, Vol. 64, Issue 11 (November 2008), pp. 1084–1098; M. Tomizawa and J. E. Casida,

“Neonicotinoid Insecticide Toxicology: Mechanisms of Selective Action,” Annual Review of Pharmacology and

Toxicology, Vol. 45 (September 2004), pp. 247-268; P. Jeschke, R. Nauen, M. Schindler, et al., “Overview of the Status

and Global Strategy for Neonicotinoids,” Journal of Agricultural and Food Chemistry, v. 59 (2011), pp. 2897-2908; and B.

Essler, “Are These Nicotine-Like Insecticides Killing Bees,” Modern Farmer, November 12, 2014. Also Center for

Food Safety (http://www.centerforfoodsafety.org/files/pesticide_list_final_59620.pdf), April 2013.

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Neonicotinoids are generally considered to be reduced-risk compared to some other types of

pesticides, and have low toxicity to mammals, birds, and fish compared to some other types of

pesticides. However, as their use has increased, so have concerns about their potential harm to

birds, earthworms, aquatic insects, and insect pollinators, including bees.19 They comprise a class

of active ingredients that have come under considerable scrutiny with respect to their potential

effects on bee health. The attention is partly due to an incident of misuse (that is, use not in

accord with the pesticide label) of one neonicotinoid, imidacloprid, in Germany20 that resulted in

a large bee kill, as well as widespread beekeeper concerns about use of another neonicotinoid,

clothianidin, and its impact on bees in France.21

Neonicotinoids are insect neurotoxins that vary in strength of their effect on honey bees.22 The

scientific evidence to date indicates that although neonicotinoids are highly toxic to bees exposed

to relatively high levels, individual pesticides in this class are not the only cause of declining bee

health, and pyrethroid exposures may be more significant.23 Although neonicotinoids have been a

focus of scientific, public, and political interest, they have not been proven to be the primary

cause of declines in bee health. Some experts, however, emphasize that research studies support

the hypothesis that “total pesticide load” is an important influence on honey bee health, probably

in combination with mite infestation, poor nutrition, viruses, and perhaps other stressors.24

Possible Role of Pesticides in Bee Health

Bees can be exposed to numerous different types of pesticides applied to field crops and other

types of plants in areas where they forage or maintain their hive.25 In addition, beekeepers may

also use pesticides registered for the control of bacteria, fungi, mites, and other bee pests. These

pesticides are applied within and in the vicinity of hives.26 Besides the active ingredients,

pesticide products include other ingredients, such as “inerts” or adjuvants that are intended to

See, for example, D. Goulson, “An Overview of the Environmental Risks Posed by Neonicotinoid Insecticides,”

Journal of Applied Ecology, vol. 50, issue 4 (2013), pp. 977–987; E. Stokstad, “Pesticides Under Fire for Risks to

Pollinators,” Science, v. 340, no. 6133 (May 10, 2013), pp. 674-676; and D. Gibbons, C. Morrisey, P. Mineau, “A

Review of the Direct and indirect Effects of Neonicotinoids and Fipronil on Vertebrate Wildlife,” Environ. Sci. Pollut.

Res., June 2014.

D. vanEngelsdorp and M. D. Meixner, “A Historical Review of Managed Honey Bee Populations in Europe and the

United States and Factors That May Affect Them,” Journal of Invertebrate Pathology, v. 103 (2010), Supp. 1, pp. S80S95.

L. Maxim and J. P. van der Sluis, “Expert Explanations of Honeybee Losses in Areas of Extensive Agriculture in

France: Gaucho® Compared with Other Supposed Causal Factors,” Environmental Research Letters, v. 5 (2010).

D. Laurino, M. Porporato, A. Patetta, et al., “Toxicity of Neonicotinoid Insecticides to Honey Bees: Laboratory

Tests,” Bulletin of Insectology, v. 64, n. 1 (2011), pp. 107-113.

Pyrethroids are synthetic pesticides modeled on the naturally occurring pyrethrins that are formed by

chrysanthemums. Most pyrethroids are more toxic and persistent than pyrethrins. Fenvalerate (an insecticide),

bifenthrin (a miticide and an insecticide), cypermethrin (an insecticide), and fluvalinate (a miticide) are pyrethroids.

J. L. Frazier, presentation to Senate staff on pesticides and bee health, April 17, 2013.

Pesticides broadly refer to chemicals used to prevent, destroy, or repel pests, such as insecticides, herbicides,

fungicides, rodenticides, and miticides, among others. Pesticides also are used to kill organisms that can cause diseases.

Some common pesticides applied deliberately to hives include formic acid (an organic acid), thymol (an essential

oil), coumaphos (an organophosphate), and fluvalinate (a pyrethroid).

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improve delivery of the active ingredient to the target pest.27 Others are used to increase the

toxicity of a pesticide, for example, by inhibiting breakdown of a pesticide by insets.28

Studies have shown that bees are exposed to pesticides in many ways throughout the foraging

period: from planter exhaust material produced during the planting of treated seed; from the soil

of both planted and unplanted fields; in flowers growing near these fields; as well as applications

in or near bee hives.29 Bees also sometimes are exposed to pesticides accidentally, either when

pesticides are misused or misapplied or when they are used according to label directions to

control pests in areas frequented by bees—for example, alongside roads or rights of way for the

control of weeds, trees, or other pests; on or near commercial farm crops; or on or near fields,

lawns, and gardens to control fleas, ticks, weeds, grubs, mosquitos, or other adult insects.

Figure 2 illustrates some significant paths of bee exposure to pesticides applied as a spray or as a

soil or seed treatment (systemic). If bees happen to fly through a newly treated field or dust

clouds from planting of seeds coated with pesticide or are orally exposed to pesticide in food or

water, and if exposure is high enough, bees may be sickened or die from pesticide exposure. With

respect to the role of pesticides in honey bee health, “[t]he most pressing research questions lie in

determining the true pesticide exposure that bees receive and the effect, if any, that pervasive

exposure to multiple pesticides have [sic] on the health and productivity of whole honey bee

colonies.”30

Pesticides are reported to have adverse local impacts on honey bees and some native bees.

Widespread use of herbicides reduces habitat available to bees;31 many pesticides are known to be

lethal to bees, given sufficient levels of exposure; and some reports of local bee kill incidents

have been well documented. Effects on individual bees may be lethal or sublethal depending on

dose and other conditions of exposure.32 A summary of the types of sublethal effects reported in

bees exposed to pesticides includes33

•

decreased navigation, orientation, and communication abilities;

•

altered foraging behavior and motor activity;

•

short- and long-term memory loss;

•

impaired learning behavior and sensory detection;

A 2012 study looked at the impact on bee health of three categories of inerts: nonionic surfactants, crop oil

concentrates, and organosilicone surfactants. Bee behavior was adversely affected after ingesting organosilicone

surfactant. Nonionic adjuvants also had a small effect, while the crop oil concentrates were inactive See T. J. Ciarlo, C.

A. Mullin, James L. Frazier, et al., “Learning Impairment in Honey Bees Caused by Agricultural Spray Adjuvants,”

PLoS ONE, v. 7, n. 7 (2012), p. e40848.

National Pesticide Information Center, Piperonyl Butoxide (fact sheet), http://npic.orst.edu/factsheets/pbogen.pdf.

See, for example, C. H. Krupke, G. J. Hunt, B. D. Eitzer, et al., “Multiple Routes of Pesticide Exposure for Honey

Bees Living Near Agricultural Fields,” PLoS ONE, v. 7. n. 1 (January 2012), p. e29268.

USDA-EPA joint report, p. 17.

J. H. Cane and V. J. Tepedino, “Causes and Extent of Declines Among Native North American Invertebrate

Pollinators: Detection, Evidence, and Consequences,” Conservation Ecology, v. 5, n. 1 (2001), p. 1.

Pesticides other than insecticides, such as fungicides or miticides, may be toxic to bees, although bees are insects and

not the targeted species.

Neonicotinoid Pesticides and Honey Bees, Washington State University Extension, Fact Sheet FS122E,

http://cru.cahe.wsu.edu/CEPublications/FS122E/FS122E.pdf; and comments by Nathalie Steinhauer (University of

Maryland) to the Virginia Native Plant Society, October 9, 2014.

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•

compromised immune functioning;

•

increased susceptibility to diseases and pests;

•

reduced fecundity (fertility and reproduction); and

•

impaired reproduction and development.

Although pesticides have been shown to damage bee health, it is unclear whether the level of

harm is sufficient to attribute pesticides as the single or as the major cause of honey bee

population declines.

Figure 2. Major Routes of Exposure of Foraging Bees to Pesticides

Source: European Food Safety Authority (EFSA), “Scientific Opinion on the Science Behind the Development of

a Risk Assessment of Plant Protection Products on Bees (Apis mellifera, Bombus spp. and Solitary Bees),” Figure

3.1, EFSA-Q-2011-00417, May 2012, http://www.efsa.europa.eu/en/efsajournal/pub/2668.htm.

The Appendix provides a summary of selected scientific literature based largely on publications

in peer-reviewed journals. In addition, a number of industry and advocacy groups have compiled

literature reviews regarding pesticide effects on bees, not all of which are specifically discussed in

this report.34 In general, studies looking at impacts of pesticides on other animal species, such as

birds, are also not addressed.35

For example, see J. Hopwood, et al., Are Neonicotinoids Killing Bees? A Review of Research into the Effects of

Neonicotinoid Insecticides on Bees, with Recommendations for Action, 2012, and A Review of Research into the

Beyond the Birds and the Bees: Effects of Neonicotinoid Insecticides on Agriculturally Important Beneficial

Invertebrates, 2013 (both prepared for Xerces Society for Invertebrate Conservation); V. Kindemba, The Impact of

Neonicotinoid Insecticides on Bumblebees, Honey Bees, and Other Non-Target Invertebrates, 2009 (Invertebrate

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Best Management Practices to Protect Pollinators

Best management practices (BMPs) are available for beekeepers, crop producers, and pesticide

applicators and include environmentally responsible pest management practices to reduce risk

and minimize pesticide exposure in bees.36 A number of states have also developed guidance to

protect pollinators. Some of these resources are listed on the Pesticide Environmental

Stewardship (PES) website37 and on EPA’s website.38

For beekeepers, guidance by apiculturists and university extension services emphasizes the

importance of reducing the exposure of bees to insecticides with high toxicity, recommending that

if such chemicals are used in an area where bees are foraging, steps may be necessary to reduce

risk of poisoning. This involves both selecting a site for an apiary in an area with low pesticide

risk and notifying “growers and applicators in the area, the county agent, and the State Apiary

Inspector of the location of your hives.... If the insecticide to be used has a long residual life and

is being applied to a plant where bees are foraging, it may be best to move your bees out of the

area.”39

For growers, recommendations involve reducing the hazards associated with insecticides,

including avoiding the use of dusts, such as those from treated seeds, and using chemicals with

reduced risk to bees whenever possible. Other recommendations include applying insecticides “in

the late evening, night, or early morning when fewer bees will be foraging, and when spray drift

and volatilization due to extreme heat are at a minimum”; not spraying “when winds favor

drifting, and us[ing] ground applications instead of air where possible”; and avoiding “spraying

when the crop or other plants in the field or nearby (including weeds) are in bloom.”40 Some

agricultural groups provide such guidance to their growers. For example, the Almond Board of

California recommends that growers avoid applying insecticides when plants are in bloom or

(...continued)

Conservation Trust); R. Heintzelman, et al., “Overview of Recent Publications on Neonicotinoids and Pollinators,”

May 2012 (prepared for Bayer Crop Science); Center for Food Safety (CFS), “Pollinators and Pesticides: A Report by

Center For Food Safety on Pollinator Health, Research, and Future Efforts for Pollinator Protection,” September 2013;

CFS, “Heavy Costs: Weighing the Value of Neonicotinoid Insecticides in Agriculture,” March 2014; CFS, Pollinator

Study Index (available at http://www.centerforfoodsafety.org/files/pollinator-study-index_73710.pdf); M. Simon,

Follow the Honey: 7 Ways Pesticide Companies are Spinning the Bee Crisis to Protect Profits, April 2014; and

PANNA, Pesticides and Honey Bees: State of the Science, May 2012.

For more information, see P. Mineau and C. Palmer, The Impact of the Nation’s Most Widely Used Insecticides in

Birds, American Bird Conservancy, March 2013; and C. A. Hallmann, et al., “Declines in Insectivorous Birds Are

Associated with High Neonicotinoid Concentrations,” Nature, vol. 511 (July 17, 2014), pp. 341-343.

Educational resources are available from most land grant universities and also the following organizations: Bee

Informed Partnership (www.beeinformed.org); Center for Urban Ecology and Sustainability/Pollinator Conservation

(www.entomology.umn.edu/cues/pollinators); National Pesticide Information Center (www.npic.orst.edu); Pesticide

Environmental Stewardship (www.pesticidestewardship.org); and Pollinator Partnership (www.pollinator.org).

PES, “Pollinator Protection,” http://pesticidestewardship.org/PollinatorProtection/Pages/default.aspx.

EPA, “Find Best Management Practices to Protect Pollinators,” http://www2.epa.gov/pollinator-protection/find-bestmanagement-practices-protect-pollinators.

C. H. Krupke, G. Hunt, and R. E. Foster, “Protecting Honey Bees from Pesticides,” Purdue University Extension, E53-W, http://extension.entm.purdue.edu/publications/E-53.pdf.

Ibid.

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when pollen is available and honey bees are feeding.41 Additional grower BMPs are listed in the

text box below.

Almond Board of California’s “Top 10 Honey Bee BMPs”

1. Communication should occur between all pollination stakeholders about pest control decisions. These

stakeholders can include beekeeper, bee broker, county agricultural commissioner, grower (owner/lessee), farm

manager, pest control adviser (PCA), and pesticide applicator.

2. Agreements should include a pesticide plan that outlines which pest control materials may be used. The grower

and the beekeeper should agree on which products may be applied if a treatment is deemed necessary. If deemed

necessary, growers should give beekeepers 48-hour notice before treatment.

3. If applying pesticides, contact your local county agricultural commissioner and give advance notification to

beekeepers with nearby managed hives.

4. Avoid applying insecticides during almond bloom until more is known, particularly about their impact on bee

brood, or young developing bees in the hive. If treatment is necessary, only apply fungicides and avoid tank-mixing

insecticides with fungicides.

5. Any fungicide application deemed necessary during bloom should occur in the late afternoon or evening, when

bees and pollen are not present. This timing avoids contaminating pollen with spray materials.

6. Provide clean water for the bees to drink. This will ensure they spend more time pollinating the crop than

searching for water. Cover or remove water sources before a pest control treatment, or empty and refill water

after a treatment is made. Check water levels throughout bloom and refresh as necessary.

7. Do not directly spray hives with any pesticide spray application. Ensure that the spray-rig driver turns off nozzles

when near hives. Spray applications that come in contact with bee hives could adversely affect bee health and the

pollination of the crop.

8. Do not hit flying bees with any spray application materials. Bees that come in contact with agricultural sprays will

not be able to fly because of the weight of spray droplets on their wings.

9. Report suspected pesticide-related bee incidents to the county agricultural commissioner’s office. Bee health

concerns cannot be addressed without the data from these incidents.

10. The beekeeper and the grower should agree on hive removal timing. The University of California recommends

bee removal when 90% of the flowers on the latest blooming variety are at petal fall. Past this point, no pollination is

taking place, and bees that forage outside the orchard (up to 4 miles) seeking alternate food sources and water will

have a higher risk of coming in contact with crops that have been treated with an insecticide.

Source: Almond Board of California, “Honey Bee BMPs,” http://www.almonds.com/newsletters/outlook/honey-beebmps-pest-management-and-honey-bees. See also http://www.growingproduce.com/nuts/top-10-honey-bee-bmps/.

Pesticide applicator BMPs recommend avoiding pesticide use when crops are blooming and

applying pesticides to blooming crops only after bees are done foraging for the day and

preferably at night.42 Bayer Crop Science notes the importance of following pesticide label

recommendations as “naturally beneficial to bees’ safety,” as well as cooperation between farmers

and beekeepers “to optimize spray times and minimize exposure to foraging bees.”43

Almond Board of California, “Honey Bee BMPs,” http://www.almonds.com/newsletters/outlook/honey-bee-bmpspest-management-and-honey-bees. See also testimony of Arthur Cummings, Capay Farms, at a House Agriculture

Subcommittee on Horticulture, Research, Biotechnology, and Foreign Agriculture hearing, April 29, 2014.

W. Buhler, “Pesticide Applicator BMPs,” Pesticide Environmental Stewardship, available at

http://pesticidestewardship.org/PollinatorProtection/PesticideApplicatorBMPs/Pages/Pesticide-Applicator-BMPs.aspx.

Bayer pamphlet, “Honey Bee Health: Understanding the Issues, Providing Solutions.”

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Such BMP guidance is generally voluntary. Several studies suggest, in general, adoption of

voluntary BMPs is characterized by both slow adoption rates (i.e., long lead times) and long lag

times between BMP adoption and observed effects; also BMP implementation tends to be mostly

self-funded.44 Some claim therefore that reliance on voluntary agricultural BMPs regarding

pesticide use and potential pollinator impacts is unlikely to produce timely behavioral changes

and BMP adoption, even with a broad outreach and education program.45

In response to recent bee die-offs in Canada, federal agencies there have instituted additional

protective requirements when using treated seed in corn and soybean production. These include

required use of safer dust-reducing seed flow lubricants; adherence to safer seed planting

practices; pesticide and seed package labels with enhanced warnings; and evaluation of the need

for neonicotinoid treatment on certain commercial crops.46 (More information on Canada’s

requirements is discussed in “Restrictions in Canada.”)

Agro-chemical industry representatives maintain that unwanted pesticide exposure is best

addressed through “effective product labeling and the implementation of meaningful stewardship

actions that help minimize harmful interactions,” along with “crop- and product-specific

integrated pest management (IPM) practices and messaging to improve bee and pollinator

safety.”47 However, some claim that because the use of systemic insecticides applied via seed

coatings is mostly “prophylactic” (i.e., applied regardless of actual pest pressure) the use of such

insecticides violates basic IPM principles, which recommend minimizing use of chemical

pesticides through pest monitoring, maximizing the use of biological and cultural controls,

applying chemical pesticides only when needed, and avoiding broad-spectrum, persistent

compounds.48 The text box below provides additional information on IPM practices.

Other guidance by apiculturists and university extension focuses on providing recommendations

to private landowners and homeowners for proper use of pest control products on ornamental

plants. One recommendation is to avoid applying any pesticides, including insecticides and

fungicides, during bloom of ornamental plants that attract bees (e.g., heather, lavender, linden,

rhododendron, and rose). It is also recommended that any pesticides be applied “only after flower

petals have fallen, when ornamental plants are less attractive to bees,” and that all specific

requirements to protect bees on the pesticide label be strictly followed.49 If pesticides are used

when plants are in bloom, those that are less toxic to bees are recommended. Some recommend

See, for example, E. Lichtenberg, D. Parker, and S. Lane, “Best Management Practice Use and Nutrient Management

in Maryland: A 2010 Snapshot,” 2010, University of Maryland; D. Stoddard, “Monitoring, Prevention and Mitigation

of Agricultural Contaminant Sources,” November 2006; Minnesota Department of Agriculture; M. Ribaudo, J. Savage,

M. Aillery, An Economic Assessment of Policy Options To Reduce Agricultural Pollutants in the Chesapeake Bay, June

2014; and American Farmland Trust, “The Adoption of Conservation Practices in Agriculture,” August 2013.

CRS communication with the Center for Food Safety, February 13, 2015.

Health Canada, “Notice of Intent, NOI2013-01, Action to Protect Bees from Exposure to Neonicotinoid Pesticides.”

Honey Bee Health Coalition, “Bee Healthy Roadmap,” October 2014, https://www.keystone.org/images/keystonecenter/spp-documents/Environment/BeeHealth/Bee-Healthy-Roadmap-October-2014.pdf. Also testimony of David

Fischer, Bayer North American Bee Care Center, at a House Agriculture Subcommittee on Horticulture, Research,

Biotechnology, and Foreign Agriculture hearing, April 29, 2014.

CRS communication with the Center for Food Safety, February 13, 2015 (citing D. Goulson, “An Overview of the

Environmental Risks Posed by Neonicotinoid Insecticides,” Journal of Applied Ecology, vol. 50, issue 4 (2013), pp.

977–987.

See, for example, Washington State Department of Agriculture (WSDA), “10 Ways to Protect Bees from Pesticides,”

AGR PUB 701-388, http://agr.wa.gov/fp/pubs/docs/388-TenWaysToProtectBeesFromPesticides.pdf.

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using certain pesticides—including products containing clothianidin, dinotefuran, imidacloprid,

and thiamethoxam—only after flower petals have fallen, and avoiding soil drench or tree

injection methods when using these products for plants known to attract bees because “these

methods may contaminate nectar and pollen for up to several years after the insecticide is

applied,” or, alternatively, recommend against buying plants treated with insecticides containing

these ingredients.50

What Is Integrated Pest Management (IPM)?

Integrated pest management (IPM) refers to practices that have been developed to improve pest control while also

minimizing risks to beneficial species, including pollinators. IPM combines pest control with an understanding of the

underlying ecology of the species and the environment where it occurs. The University of California Statewide

Integrated Pest Management Program (UC IPM) defines IPM as:

an ecosystem-based strategy that focuses on long-term prevention of pests or their damage through

a combination of techniques such as biological control, habitat manipulation, modification of cultural

practices, and use of resistant varieties. Pesticides are used only after monitoring indicates they are

needed according to established guidelines, and treatments are made with the goal of removing only

the target organism. Pest control materials are selected and applied in a manner that minimizes risks

to human health, beneficial and nontarget organisms, and the environment.

EPA further states: “IPM relies on easy-to-implement, environmentally sensitive practices that prevent pests from

becoming a threat. These practices involve monitoring and identifying pests and taking preventive action before

pesticides are used. If pesticides are needed, methods such as targeted spraying may be used.” In IPM strategies,

pesticides may be considered part of IPM but generally are intended as a last resort, after other non-chemical

methods have been exhausted or proved to be ineffective or are not available. According to UC IPM, pesticides are

used “only when needed and in combination with other approaches for more effective, long-term control,” and “are

selected and applied in a way that minimizes their possible harm” to humans and other organisms, as well as the

environment (air, soil, and water quality). The U.S. Fish and Wildlife Service (FWS) further states that in addition to

reducing risks from pests and pest management-related strategies to people, property, resources, and the

environment, one of the other benefits of IPM is the ability to “decrease or eliminate unnecessary pesticide use.”

In January 2014, EPA announced it had awarded nearly $500,000 in agricultural grants for IPM practices to reduce

the use of potentially harmful pesticides and lower risk to bees. These grants are intended to expand public-private

stewardship efforts and reduce pesticide risk in agriculture. These IPM grants were awarded to Louisiana State

University, Pennsylvania State University, and the University of Vermont.

Source: UC IPM website: http://www.ipm.ucdavis.edu; FWS, “Integrated Pest Management: Reducing the Risks to

Pollinators from Pest Management Activities;” and EPA’s press release, “EPA Awards Almost Half a Million in

Funding to Three Universities for Projects to Reduce Pesticide Risk Including Risks to Bees,” January 8, 2014. See

also USDA, Natural Resources Conservation Service (NRCS), “Integrated Pest Management Plan Criteria

Practice/Activity Code (114) (No.),” September 2011.

Consumer campaigns have been initiated to encourage businesses and home gardening centers to

stop selling certain pesticides or plants treated with these products because of concerns about the

effects on bees and other pollinators.51 A consumer campaign initiated by the Center for Food

Safety highlights that more than 60 commonly used home and garden products contain

neonicotinoid pesticides and recommends that homeowners avoid certain commonly used

pesticide products.52 In addition, concerns have been raised about the use of mosquito control

Ibid.

See, for example, Xerxes, “Protecting Bees from Neonicotinoid Insecticides in Your Garden,” 2013; J. Hopwood and

M. Shepherd, “Neonicotinoids in Your Garden,” 2012; and Friends of the Earth, Gardeners Beware: Bee-Toxic

Pesticides Found in “Bee-Friendly” Plants, June 2014 (updated).

For a listing of these products, see Center for Food Safety, “Help Save the Bees,” April 2013,

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services by some homeowners, because of potential adverse effects to bees and other beneficial

insects that might feed on plants or be exposed to pesticides within the sprayed areas, as well as

effects to species on adjacent or nearby property due to drift.

Federal Agency Efforts

National Pollinator Health Strategy (“Presidential Memorandum”)

In June 2014, the Obama Administration issued its Presidential Memorandum, “Creating a

Federal Strategy to Promote the Health of Honey Bees and Other Pollinators,” directing federal

agencies to take steps to protect and restore domestic populations of pollinators.53 It established a

“Pollinator Health Task Force,” co-chaired by USDA and EPA, with representatives of the

Departments of State, Defense, the Interior, Housing and Urban Development, Transportation,

Energy, and Education; among other agencies and offices.

The task force is directed to develop a National Pollinator Health Strategy, which is to include a

Pollinator Research Action Plan to “focus federal efforts on understanding, preventing, and

recovering from pollinator losses.” Among the many activities expected to inform the action plan

is “identification of existing and new methods and best practices to reduce pollinator exposure to

pesticides, and new cost-effective ways to control bee pests and diseases.” Task force member

agencies will develop plans to increase and improve pollinator habitat. These plans may include

“use of integrated vegetation and pest management,” among other actions. Member agencies will

also “make any necessary and appropriate changes to enhance pollinator habitat on federal lands

through the use of integrated vegetation and pest management and pollinator-friendly best

management practices.” The task force is expected to release its National Pollinator Health

Strategy in spring 2015.54

In November 2014, USDA and EPA held a number of public listening sessions to inform the task

force members. Concerns about pesticide use were among the major discussion points.

Commercial beekeepers, environmental groups, and some food businesses55 continue to push for

restrictions on pesticide use and question whether other factors, such as parasitic mites, are the

primary driver behind bee declines. Most pesticide industry groups and commercial growers

continue to encourage broader consideration beyond pesticides and claim that some alternative

pesticides are more toxic than neonicotinoids.56

(...continued)

http://www.centerforfoodsafety.org/files/pesticide_list_final_59620.pdf.

White House, “Presidential Memorandum—Creating a Federal Strategy to Promote the Health of Honey Bees and

Other Pollinators,” June 20, 2014, http://www.whitehouse.gov/the-press-office/2014/06/20/presidential-memorandumcreating-federal-strategy-promote-health-honey-b.

Announcement by Michael Stebbins, White House Office of Science and Technology Policy, at the 14th annual

conference of the North American Pollinator Protection Campaign (NAPPC), October 22, 2014. Other information is

available in CRS Report R43191, Bee Health: Background and Issues for Congress.

See, for example, letter to U.S. President Barack Obama from more than 100 environmentally friendly food

companies urging the Administration to protect bees and other pollinators from pesticides, January 13, 2015.

J.R. Pegg, “Neonicotinoid Controversy Hits Pollinator Health,” Food Chemical News, December 3, 2014.

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Currently, at EPA, the agency’s pollinator strategic plan outlines efforts to advance scientific

knowledge and assessment of pesticide risks to pollinators; improve management tools for

mitigating risks to pollinators; and increase and broaden communication and public outreach.57

USDA-EPA Joint Report

In 2013, USDA and EPA published a joint report, National Stakeholders Conference on Honey

Bee Health.58 Among the goals of the conference were to “synthesize the current state of

knowledge regarding CCD, bee pests, pathogens, and nutrition, potential pesticide effects on

bees, and bee biology, genetics and breeding.” The report’s key findings include

recommendations to address risks to honey bees from parasites and disease; increase the genetic

diversity in bee colonies; and improve nutrition for honey bees. In addition, regarding pesticides,

the report acknowledged the following needs:59

•

Collaboration and Information Sharing. Best management practices (BMPs)

associated with pesticide use and bees are known but are not widely or

systematically followed by U.S. crop producers. “Informed and coordinated

communication between growers and beekeepers” is needed, along with

“effective collaboration between stakeholders on practices to protect bees from

pesticides.” Beekeepers have identified the need for “accurate and timely bee kill

incident reporting, monitoring, and enforcement.”

•

Additional Pesticide Research. According to EPA, “[t]he most pressing

pesticide research questions relate to determining actual pesticide exposures and

effects of pesticides on bees in the field and the potential for impacts on bee

health and productivity of whole honey bee colonies.”

The National Honey Bee Health Stakeholder Conference Steering Committee is made up of

representatives from Pennsylvania State University; from USDA’s Office of Pest Management

Policy (OPMP), National Institute of Food and Agriculture (NIFA), Agricultural Research Service

(ARS), Animal and Plant Health Inspection Service (APHIS), Natural Resources Conservation

Service (NRCS), and National Agricultural Statistics Service (NASS); and from EPA’s Office of

Pesticide Programs (OPP). Much of the current research on bee health is being conducted by

scientists at USDA and its Beltsville bee laboratory, by the USDA-supported Bee Informed

Partnership, and by scientists at many of the land-grant universities nationwide.60

EPA, Pollinator Protection Strategic Plan, http://www2.epa.gov/pollinator-protection/pollinator-protection-strategicplan.

USDA, Report on the National Stakeholders Conference on Honey Bee Health, National Honey Bee Health

Stakeholder Conference Steering Committee, May 2013, http://www.usda.gov/documents/ReportHoneyBeeHealth.pdf.

EPA news release, “USDA and EPA Release New Report on Honey Bee Health,” May 2, 2013.

More information is available in CRS Report R43191, Bee Health: Background and Issues for Congress.

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Environmental Protection Agency

EPA’s Pesticide Registration Review of Neonicotinoid Pesticides

Neonicotinoid pesticide registrations are being reviewed by EPA. According to EPA:61

Some uncertainties have been identified since their initial registration regarding the potential

environmental fate and effects of neonicotinoid pesticides, particularly as they relate to

pollinators. Data suggest that neonicotinic residues can accumulate in pollen and nectar of

treated plants and may represent a potential exposure to pollinators.

Adverse effects data as well as beekill incidents have been reported, highlighting the

potential direct and/or indirect effects of neonicotinic pesticides. Therefore, among other

refinements to ecological risk assessment during registration review, we will consider

potential effects of the neonicotinoids to honeybees and other pollinating insects.

Review of several neonicotinoid pesticide registrations began December 2011, with review of

imidacloprid starting a few years earlier, in December 2008 (Table 1). EPA aims to review all

neonicotinoids as a group.

Table 1. Schedule for EPA Review of Neonicotinoid Pesticides

Chemical Name and Docket Number

Initiation

Data Generation

Projected Completion

Imidacloprid (EPA-HQ-OPP-2008-0844)

Dec. 2008

2010-2015

2016-2017

Clothianidin (EPA-HQ-OPP-2100-0865)

Dec. 2011

2013-2016

2017-2018

Thiamethoxam (EPA-HQ-OPP-2011-0581)

Dec. 2011

2013-2016

2017-2018

Dinotefuran (EPA-HQ-OPP-2011-0920)

Dec. 2011

2013-2016

2017-2018

Acetamiprid (EPA-HQ-OPP-2012-0329)

Dec. 2012

2014-2017

2018-2019

Thiacloprid (EPA-HQ-OPP-2012-0218)

Dec. 2012

2014-2017

2018-2019

Source: EPA’s website, http://www2.epa.gov/pollinator-protection/schedule-review-neonicotinoid-pesticides.

In July 2014, the Natural Resources Defense Council (NRDC) petitioned EPA to conduct an

emergency review of the impacts of neonicotinoid pesticides on bees and to complete its review

within one year.62 At an October 2014 meeting, an EPA official indicated that the agency would

move up its dates for its review of neonicotinoid pesticides from 2018-2019 to 2016-2017.63

Currently, among the neonicotinoid pesticides under review, some products are being used under

a “conditional” registration, while some products are being used under an “unconditional”

registration. FIFRA provides that EPA register a pesticide if, among other findings, it meets the

statutory standard, namely: (1) the pesticide will perform its intended function without

EPA, “Groups of Pesticides in Registration Review,” http://www2.epa.gov/pesticide-reevaluation/groups-pesticidesregistration-review.

NRDC, “Petition for Interim Administrative Review of Neonicotinoid Pesticides,” filed July 7, 2014,

http://docs.nrdc.org/health/files/hea_14070701a.pdf.

Public statements by EPA’s Assistant Administrator for the Office of Chemical Safety and Pollution Prevention, Jim

Jones, at the 14th Annual NAPPC International Conference, October 22, 2014.

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unreasonable adverse effects on human health and the environment, and (2) the pesticide will not

generally cause unreasonable adverse effects on human health and the environment when used in

accordance with widespread and commonly recognized practice. Under an unconditional

registration, after reviewing the data and information submitted to support an

applicant/registrant’s pesticide product application under consideration, if EPA determines that

the pesticide meets the statutory standard and there are no outstanding data requirements, the

agency may approve an “unconditional” registration.64 If, however, EPA finds that the pesticide

meets the standard for registration, but there are outstanding data requirements, the agency may,

under certain circumstances, grant a “conditional” registration.65 Before granting a conditional

registration, EPA must determine that, although an application lacks some of the necessary data,

use of the pesticide would not significantly increase the risk of unreasonable adverse effects on

the environment during the time needed to generate the necessary data. A product’s “conditional”

or “unconditional” status is determined on a product registration by product registration basis, and

not for the pesticide’s active ingredient as a whole.66 An indication of a product’s current status

can be found at EPA’s searchable label database.67

The U.S. Government Accountability Office (GAO) has conducted studies that are critical of

EPA’s pesticide registration process, particularly regarding the program’s conditional

registrations.68 Environmental and other groups argue that conditional registrations are a loophole

in EPA’s requirements, allowing pesticides onto the market that might not otherwise be allowed

under a thorough agency review.69 These groups further claim that EPA has overused conditional

registrations and that the agency does not have a reliable data-gathering system to track

conditional registrations.70 GAO’s 2013 report states that “the total number of conditional

registrations granted is unclear” due to database inaccuracies and confusion in EPA’s

recordkeeping system for tracking pesticides.71

In the process of reviewing registrations for neonicotinoids, EPA has revised its risk assessment

process “to reflect advancements in the state of the science that underlie bee exposure and effects

assessments.”72 The draft risk assessment policy was released to the public, and materials were

distributed and discussed at a FIFRA Scientific Advisory Panel (SAP) meeting in September

2012.73 The final risk assessment guidance was released in June 2014.74 The guidance is founded

FIFRA section 3(c)(5).

FIFRA section 3(c)(7).

For more information, see EPA’s website: http://www2.epa.gov/pesticide-registration/conditional-pesticideregistration.

A pesticide’s labels and the indication of their current conditional (or not) status at EPA’s Label database:EPA,

“Pesticide Product Label System,” http://iaspub.epa.gov/apex/pesticides/f?p=PPLS:1.

See, for example, GAO, EPA Should Take Steps to Improve Its Oversight of Conditional Registrations, GAO-13145, August 2013; and GAO, EPA’s Formidable Task To Assess and Regulate Their Risks, RCED-86-125: April 1986.

J. Sass and M. Wu, “Superficial Safeguards: Most Pesticides Are Approved by Flawed EPA Process,” NRDC Issue

Brief, IB: 13-01-B, March 2013, http://www.nrdc.org/health/pesticides/files/flawed-epa-approval-process-IB.pdf.

Ibid.

See, for example, GAO, EPA Should Take Steps to Improve Its Oversight of Conditional Registrations, GAO-13145, August 2013.

EPA, Environmental Fate and Effects Division (EFED), EFED Response to Comments Submitted to the Clothianidin

Registration Review Docket (docket: EPA-HQ-OPP-2011-0865), June 11, 2012. References EPA’s interim guidance

from 2011, Pesticides: Science and Policy, Interim Guidance on Honey Bee Data Requirements.

Meeting materials and public comments are posted in the regulatory docket (docket: EPA-HQ-OPP-2012-0543).

EPA, “Proposed Decision Framework for Assessing Risks of Pesticides to Honey Bees,” presentation at the 2012

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on EPA’s ecological risk assessment framework, integrates an analysis of honey bees and other

pollinators within the agency’s broader components of ecological risk assessment, and was

prepared in collaboration with Health Canada’s Pesticide Management Regulatory Authority and

California’s Department of Pesticide Regulation. The guidance describes the basic framework of

the risk assessment process and the data used to support risk management decisions, and includes

a process to assess both foliar spray applications and soil/seed treatment applications.

Some groups argue that EPA does not take into account chronic, sub-lethal effects in its risk

assessments, nor synergistic effects with other compounds used in real field settings, such as

fungicides, adjuvants, and inerts.75 These groups also claim native and wild bee species are

generally not addressed as part of EPA’s risk assessment. Since most native bee species (about

70%) are ground nesting,76 these groups further claim that the use of systemic insecticides poses

risks to native bees from exposure through their habitats in the ground. Native and wild bee

species are also generally not addressed as part of EPA’s pesticide labeling approach (discussed in

“EPA’s New “Bee Advisory” Labeling Requirements”).

As part of EPA’s overall review, the agency has conducted a study of the benefits of neonicotinoid

seed treatments for insect control in U.S. soybean production.77 EPA’s analysis concluded: “these

seed treatments provide little or no overall benefits to soybean production in most situations.

Published data indicate that in most cases there is no difference in soybean yield when soybean

seed was treated with neonicotinoids versus not receiving any insect control treatment.”78

Reportedly, EPA also studied the potential benefits of neonicotinoid seed treatments to corn

production but has not published those findings.79 In 2013, EPA and USDA conducted a summit

with stakeholders on reducing exposure to dust from treated seed and potential acute exposure of

honey bees and pollinators to pesticides. Information and stakeholder presentations from the

summit are at EPA’s website.80

EPA’s Consideration to Modify Thiamethoxam Tolerance Levels

In September 2014, EPA announced that it had received “several initial filings of pesticide

petitions requesting the establishment or modification of regulations for residues of pesticide

chemicals in or on various commodities,” including a petition by Syngenta that EPA increase the

allowable threshold for residues of thiamethoxam.81 Syngenta’s petition would apply to alfalfa,

(...continued)

FIFRA SAP meeting. Also see EPA’s presentation, “Ecological Risk Assessment Process for Honey Bees.”

EPA, Guidance for Assessing Pesticide Risks to Bees, June 19, 2014, http://www2.epa.gov/sites/production/files/

2014-06/documents/pollinator_risk_assessment_guidance_06_19_14.pdf.

CRS communication with the Center for Food Safety, February 13, 2015.

USDA, “Enhancing Nest Sites For Native Bee Crop Pollinators,” Agroforestry Notes, AF Note 34, September 2007.

EPA, “Benefits of Neonicotinoid Seed Treatments to Soybean Production,” October 15, 2014, http://www2.epa.gov/

sites/production/files/2014-10/documents/benefits_of_neonicotinoid_seed_treatments_to_soybean_production_2.pdf.

EPA, “Benefits of Neonicotinoid Seed Treatments to Soybean Production,” October 15, 2014. See also

http://www2.epa.gov/pollinator-protection/benefits-neonicotinoid-seed-treatments-soybean-production

Public statements by EPA’s Assistant Administrator for the Office of Chemical Safety and Pollution Prevention, Jim

Jones, at the 14th Annual NAPPC International Conference, October 22, 2014.

EPA, “Summit on Reducing Exposure to Dust from Treated Seed,” http://www2.epa.gov/pollinator-protection/2013summit-reducing-exposure-dust-treated-seed.

79 Federal Register 172: 53009: September 5, 2014.

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barley, corn and wheat, both the crop itself and the straw and stover82 left over after cultivation.

According to some reports, the petition seeks to increase the tolerance levels ranging from about

1.5 times current levels for stover from sweet corn to about 400 times current levels for hay from

wheat.83 EPA’s review of this request is still pending. Thiamethoxam is one of the neonicotinoid

pesticides banned for use in the European Union.

EPA’s New “Bee Advisory” Labeling Requirements

In August 2013, EPA announced that it had developed new pesticide labels that prohibit use of

some neonicotinoid pesticide products where bees are present. The new requirements apply to

foliar applications of products containing imidacloprid, dinotefuran, clothianidin, thiamethoxam,

tolfenpyrad, and cyantraniliprole.84 Exceptions apply under certain conditions for agricultural

crops and commercially grown ornamental plants. The new labels require a “Pollinator Protection

Box” (or “bee advisory,” Figure 3) and bee icon with information on routes of exposure and

spray drift precautions, as well as new language added under “Directions for Use.”

Figure 3. EPA’s Bee Advisory Box

Source: EPA, http://www2.epa.gov/sites/production/files/2013-11/documents/bee-label-info-graphic.pdf.

Stover refers to the leaves and stalks of field crops, such as corn or soybeans, commonly left in a field after harvest.

T. Stecker, “Syngenta Asks EPA to Raise Tolerance Level for ‘Bee-Killing’ Chemical,” Greenwire, September 5,

2014.

EPA, “New Pesticide Labels Will Better Protect Bees and Other Pollinators,” press release, August 15, 2013; and

letter from EPA’s Office of Investigations to the Pollinator Stewardship Council, February 28, 2014. See also letters

from EPA to registrants of nitroguanidine neonicotinoid products, July 22, 2013, and August 15, 2013.

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The bee advisory will, among other things, alert pesticide applicators to restrictions regarding

certain pesticides when bees are present; clarify that pesticides cannot be applied until all petals

have fallen; and emphasize the importance of avoiding pesticide drift (for example, due to wind)

to other areas where bees may be present. The new bee icon will signal the pesticide’s potential

hazard to bees, and warns that direct contact and ingestion can harm pollinators. Information is at

EPA’s website.85

EPA’s new labeling requirements have received mixed reviews from beekeepers, who argue that

the new labels are inadequate and include exceptions that may make them less protective for bees

and other pollinators.86 Groups, such as the Pollinator Stewardship Council, have expressed

concerns about EPA’s label as well as concerns about the conditions under pesticide applications

would be allowed. Figure 4 shows some of this group’s concern with EPA’s label, including

concerns that none of the terms in the label is defined and many are ambiguous (which they claim

makes the requirements unenforceable), as well as the concern that the label refers applicators to

a pesticide industry website, among several other issues.87

Figure 4. Pollinator Stewardship Council’s Analysis of EPA’s Bee Advisory Box

Source: Pollinator Stewardship Council. Other comments regarding exceptions to the label’s requirements are

at http://pollinatorstewardship.org/wp-content/uploads/2014/02/PSC-label-layout-of-concerns.pdf.

EPA, “New Labeling for Neonicotinoid Pesticides,” http://www2.epa.gov/pollinator-protection/new-labelingneonicotinoid-pesticides.

J. R. Pegg, “State Pesticide Officials, EPA Ready to Join Forces on Pollinator Protection,” Food Chemical News,

December 10, 2014.

For more information, see Pollinator Stewardship Council, “Analysis of the New Label,”

http://pollinatorstewardship.org/wp-content/uploads/2014/02/PSC-label-layout-of-concerns.pdf.

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Some groups, including the Pollinator Stewardship Council, have voiced concerns about EPA’s

exceptions to the new labeling requirements, which would allow application under certain

conditions.88 Exceptions to the labeling requirements are as follows.

For “Crops Grown Under Contracted Pollination Services,” the label for some neonicotinoid

pesticide products states: “Do not apply this product while bees are foraging” or “until flowering

is complete and all petals have fallen.” Exceptions are allowed for in cases where “an application

must be made when managed bees are at the treatment site, the beekeeper providing the

pollination services must be notified no less than 48 hours prior to the time of the planned

application so that the bees can be removed, covered or otherwise protected prior to spraying.”

For “Food Crops and Commercially Grown Ornamentals not Under Contract for

Pollination Services But Attractive to Pollinators,” the label for some products also states: “Do

not apply this product while bees are foraging” or “until flowering is complete and all petals have

fallen.” Exceptions are allowed for in cases where:

•

The application is made to the target site after sunset.

•

The application is made to the target site when temperatures are below 55˚F.

•

The application is made in accordance with a government-initiated public health

response.

•

The application is made in accordance with an active state-administered apiary

registry program where beekeepers are notified no less than 48 hours prior to the

time of the planned application so that the bees can be removed, covered, or

otherwise protected prior to spraying.

•

The application is made due to an imminent threat of significant crop loss, and a

documented determination consistent with an IPM plan or predetermined

economic threshold is met. Every effort should be made to notify beekeepers no

less than 48 hours prior to the time of the planned application so that the bees can

be removed, covered, or otherwise protected prior to spraying.

Among the expressed concerns regarding EPA’s exceptions to its label advisory are:89

•

harm caused by foliar application of the affected pesticides will be the

responsibility of the beekeeper, including damage or die-off from applications

allowed for under the labels exceptions;

•

uncertainty about what constitutes notifying a beekeeper to move their bees, and

concern that native bees will be harmed since they are not similarly managed;

•

foliar application of adjacent or nearby sites may affect bees since they have a 3mile to 7-mile forage range;

•

exceptions to applications made when temperatures are below 55˚F may affect

bees that forage at temperatures as low as 45˚F; and

Letter from EPA to registrants of nitroguanidine neonicotinoid products, August 15, 2013.

Pollinator Stewardship Council, http://pollinatorstewardship.org/wp-content/uploads/2014/02/PSC-label-layout-ofconcerns.pdf. See also blog posting, March 21, 2014, http://pollinatorstewardship.org/?p=2143.

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•

other labeling issues, including who decides when foliar treatments are needed,

what are the criteria for determining whether treatment are needed, where should

beekeepers transport bees during applications, and who determines what

mitigation measures are appropriate.

Exceptions do not apply to non-agricultural crops, such as ornamental crops grown by

homeowners, and the pesticide label requires that the product not be applied while bees are

foraging or when plants are flowering.

EPA Support of State Pollinator Protection Plans

EPA is working with states to draft guidance on the development of EPA-approved, statemanaged pollinator protection plans. Guidance is being developed by EPA’s State FIFRA

Research and Evaluation Group (SFIREG), and will outline a process for reviewing and accepting

state pollinator protection plans as part of EPA’s broader pollinator protection efforts related to

pesticides. The draft guidance was presented at a December 2014 meeting of the Association of

American Pesticide Control Officials (AAPCO),90 and contained information on the core

elements for EPA-approved state pollinator plans, the process for EPA review and updating of

state plans, how to reference state plans through labeling requirements, and how to access

recommended best management practices.91 Pollinator protection plans are in place in several

states, including California, Colorado, Florida, Mississippi, and North Dakota.92 Other states are

considering similar initiatives.

EPA Development of Voluntary Controls for Pesticide Drift

In October 2014, EPA announced a new voluntary Drift Reduction Technology (DRT) program to

encourage the use of verified, safer pesticide spray products to reduce exposure and pesticide

movement, and also to reduce costs to farmers from pesticide loss. EPA defines pesticide spray

drift as the “movement of pesticide dust or droplets through the air at the time of application or

soon after, to any site other than the area intended.”93 More information is at EPA’s website.94 A

similar effort—the DriftWatch Specialty Crop Site Registry—provides for a voluntary

communication tool between crop producers, beekeepers, and pesticide applicators, and is

intended to protect high-value, pesticide-sensitive crops and commodities before applying

pesticides.95 The program is currently in use in many midwestern and mid-Atlantic states.

SFIREG Full Committee meeting, December 8, 2014, http://aapco.org/meetings/agen-120814.pdf.

C. Purdy, “EPA to Review State Pollinator Protection Plans,” Politico Morning Agriculture, December 9, 2014.

J.R. Pegg, “State Pesticide Officials, EPA Ready to Join Forces on Pollinator Protection,” Food Chemical News,

December 10, 2014.

EPA, “Introduction to Pesticide Drift,” http://www2.epa.gov/reducing-pesticide-drift/introduction-pesticide-drift.

Pesticide droplets are produced by spray nozzles used in application equipment for spraying pesticides on crops,

forests, turf, and home gardens. Dust formulations refer to very fine dry particles of pesticides.

EPA, “Reducing Pesticide Drift,” http://www2.epa.gov/reducing-pesticide-drift.

Information is at DriftWatch’s website: https://www.driftwatch.org/.

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Fish and Wildlife Service Memorandum

In July 2014, the U.S. Fish and Wildlife Service (FWS) in the Department of the Interior

announced that it would phase out the feeding of genetically engineered crops to wildlife and the

use of neonicotinoid pesticides in all of its wildlife refuges by January 2016.96

Initially this decision was meant to phase out the use of neonicotinoids in Region 1 only, which

covers Oregon, Washington, Idaho, Hawaii, and the Pacific Islands.97 Under the guidelines,

refuge managers will also need to comply with new mandatory requirements for all chemically

treated seeds on refuge lands.98

In early 2013, Representative Austin Scott, chairman of a House Agriculture subcommittee,

indicated that the committee would direct FWS to undergo “a uniform risk assessment process ...

when making decisions on products already approved” under FIFRA and/or the Plant Protection

Act.99 To date, no such action has been untaken.

Other Ongoing Efforts

Restrictions in Some U.S. Cities and Counties

A number of cities and counties, among other local jurisdictions, have instituted restrictions on

the use of neonicotinoid pesticides in an effort to protect pollinators. In March 2014, Eugene,

Oregon, became the first U.S. city to restrict neonicotinoid use. (Despite the ban, a mass die-off

of bees was reported in June 2014 at an apartment complex in northwest Eugene. It was attributed

to insecticide sprayed on blooming linden trees.) Since then other cities have also instituted bans,

including Seattle and Spokane in Washington; Shoreline, Minnesota; and Skagway, Alaska. Other

cities and counties, such as Tucson and Pima County in Arizona, and Boulder County in

Colorado, also are considering restrictions. Some state legislatures, including Alaska, California,

Maryland, Minnesota, New York, New Jersey, Oregon, and Vermont, have considered legislation

to further study and/or restrict neonicotinoid use. Some localities also have instituted other types

of pesticide restrictions, such as with disclosure laws in the county of Kauaˋi in Hawaii. Other

localities have implemented programs to encourage households and municipalities to pledge to

create “pollinator-friendly, toxin-free ecosystem habitats,” such as in the city and county of

Denver, Colorado. Some state agencies are actively studying the issue.100

FWS memorandum, “Use of Agricultural Practices in Wildlife Management in the National Wildlife Refuge

Service,” July 17, 2014, http://www.peer.org/assets/docs/fws/FWS_Memorandum.pdf.

T. Stecker, “FWS Bans GMO Feed, Bee-Killing Chemicals Nationwide,” Greenwire, August 1, 2014.

See Region 1 FWS memorandum, “Guidelines Regarding the Interim Use and Phase Out of Neonicotinoid

Insecticides to Grow Agricultural Crops for Wildlife on NWRs in the Pacific Region,” June 9, 2014.

OpEd by U.S. Representative Austin Scott, “Protecting Bee Health Is a Long-Term Commitment,” Agri-Pulse, 2013.

100

See, for example, Minnesota Department of Agriculture Pesticide and Fertilizer Management Division, Scoping a

Review of Neonicotinoid Use, Registration and Insect Pollinator Impacts in Minnesota, March 2014 (draft).

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In addition, several states—California, Colorado, Florida, Mississippi, and North Dakota—have

state pollinator protection plans in place, and other states are considering similar initiatives.101

(For information, see “EPA Support of State Pollinator Protection Plans”)

Restrictions in the European Union

Like the rest of the world, the countries of the EU have experienced overwinter honey bee colony

losses. As reported by the nonprofit honey bee research association, COLOSS,102 overwinter

colony losses averaged 9% in 2013/2014, the lowest since the group began collecting such data in

2007.103 Across countries, losses ranged from 6% to 12%. This is lower than results reported for

2012/2013, when overwinter losses ranged from 6% to a high of 37% across all reporting

countries.104 Another report commissioned by the European Commission and EU member states

concluded honey bee colony mortalities were “better than previously expected” and “higher than

normal in certain countries, with significant regional (and possibly temporal) differences.”105

In response to concerns about declining bee populations, in May 2013, the European Commission

(EC) adopted Regulation No 485/2013 banning the use of certain neonicotinoid pesticides for a

period of two years, among other proposed limits on the use of other pesticides.106 The regulation

includes the following provisions:

•

use of three neonicotinoid pesticides—clothianidin, imidacloprid, and

thiamethoxam—is restricted for seed treatment, soil application (granules), and

foliar treatment on bee attractive plants and cereals;

•

any authorized uses are available to professionals only;

•

any exceptions to these restrictions are limited to treating bee-attractive crops in

greenhouses or in open-air fields after flowering; and

•

restrictions are to be maintained for two years, effective December 1, 2013.

As new information becomes available, the EC will review the approval conditions for these three

pesticides and take into account relevant scientific and technical developments. Previous

mitigation measures (EC Regulation No 1107/2009) restricted spraying of insecticides on beeattractive flowering crops.107

101

J.R. Pegg, “State Pesticide Officials, EPA Ready to Join Forces on Pollinator Protection,” Food Chemical News,

December 10, 2014.

102

COLOSS (Prevention of honeybee COlony LOSSes), http://www.coloss.org/, collects data from 19 European

countries, and also from Israel and Algeria.

103

COLOSS, “Losses of Honey Bee Colonies over the 2013/14 Winter,” July 18, 2014.

104

COLOSS, “Losses of Honey Bee Colonies over the 2012/13 Winter,” July 24, 2013.

105

EpiloBee, “A Pan-European Epidemiological Study on Honeybee Colony Losses 2012-2013,” August 2014. See

also OPERA Research Center, Bee Health in Europe—Facts & Figures and Bee Health in Europe, An Overview, 2012,

http://www.operaresearch.eu/.

106

Regulation (EC) No 485/2013 of 24 May 2013 amending Implementing Regulation (EU) No 540/2011, as regards

the conditions of approval of the active substances clothianidin, thiamethoxam and imidacloprid, and prohibiting the

use and sale of seeds treated with plant protection products containing those active substances. See also European

Commission, “Bees & Pesticides: Commission Goes Ahead with Plan to Better Protect Bees,” http://ec.europa.eu/food/

archive/animal/liveanimals/bees/neonicotinoids_en.print.htm.

107

Restrictions were placed in some member states, such as Italy (ban on corn seed coating), Slovenia (ban on corn and

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The EC’s 2013 regulatory action was in response to the European Food Safety Authority’s

(EFSA)108 scientific assessment that identified “high risks for bees for some uses of three

neonicotinoids (imidacloprid, clothianidin and thiamethoxam) and fipronil,” such that “the

approval criteria of these pesticides were no longer satisfied.”109 Regarding the three restricted

pesticides, EFSA identified “high acute risks” for bees from exposure to pesticides associated

with the production of several crops such as corn, grains, and sunflower, as well as exposure to

residue in pollen and nectar in certain crops.110

The EU Commission has further proposed to restrict the use of fipronil, an insecticide which

EFSA has identified as posing an acute risk to Europe’s honey bees when they are exposed to

seeds treated with the chemical.111

Other reports, such as a study published by the United Kingdom’s Department for Environment,

Food and Rural Affairs (DEFRA), dispute some of the findings linking bee health and exposure to

neonicotinoids.112 Other studies also highlight the likely multifaceted nature of possible factors

contributing to pollinator declines.113 Researchers in Europe continue to study this issue and

reportedly are in the process of completing a large-scale study reviewing the landscape-scale

effects of neonicotinoid use on crops.114 Some member state officials are also questioning the ban

and its possible effects on agricultural production.115

(...continued)

sugar beet seed coating), France (ban on corn and canola seed coating), and Germany (ban on corn seed coating). M.

Dermine, “Neonicotinoids in the European Union,” presentation at November 4, 2014, webinar.

108

EFSA is an agency of the European Union that provides independent scientific advice and communication on

existing and emerging risks associated with food and feed safety.

109

EC, “Bee Health: What Is the EU Doing? Questions and Answers,” April 7, 2014 http://europa.eu/rapid/pressrelease_MEMO-14-260_en.htm. See also EC press releases, “Bee Health: EU-Wide Restrictions on Pesticide Use to

Enter into Force on 1 December,” May 24, 2013; and “Bees and Pesticides: Commission to Proceed with Plan to Better

Protect Bees,” April 29, 2013.

110

Regarding the EFSA study, EPA claims its own scientific conclusions “are similar to those expressed in the EFSA

report with regard to the potential for acute effects and uncertainty about chronic risk,” but notes “the EFSA report does

not address risk management” which is a requirement for EPA under U.S. law. See EPA, “Colony Collapse Disorder:

European Bans on Neonicotinoid Pesticides,” August 2013, http://www.epa.gov/pesticides/about/intheworks/ccdeuropean-ban.html.

111

EC, “Bee Health: EU Takes Additional Measures on Pesticides to Better Protect Europe’s Bees,” July 16, 2013,

http://europa.eu/rapid/press-release_IP-13-708_en.htm. EFSA’s analysis, “Conclusion on the Peer Review of the

Pesticide Risk Assessment for Bees for the Active Substance Fipronil,” EFSA Journal 2013, 11(5):3158, 27 May 2013,

http://www.efsa.europa.eu/en/efsajournal/pub/3158.htm.

112

See, for example, DEFRA, Food and Environment Research Agency (FERA), “Effects of Neonicotinoid Seed

treatments on Bumble Bee Colonies Under Field Conditions,” March 2013.

113

See, for example, a 2013 study by the European Landowners’ Organization (ELO), the European Crop Protection

Association (ECPA), and the European Initiative for Sustainable Development in Agriculture (EISA), “Pollinators and

Agriculture: Agricultural Productivity and Pollinator Protection.”

114

P. Case, “Neonicotinoid Field Studies to Assess Effect on Bees,” Farmers Weekly, September 26, 2014. Reportedly,

large-scale field experiments will look at the effects on bees of two seed treatments—clothianidin and thiamethoxam.

115

See, for example, N. Robinson, “Neonic Ban Threatens UK Mustard Crop,” FoodManufacture, August 19, 2014;

and M McGrath, “Scientific opinions differ on bee pesticide ban,” BBC News, April 23, 2013.

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Restrictions in Canada

In Canada, the Canadian Association of Professional Apiculturists (CAPA) reports that overwinter

honey bee colony losses in 2013/2014 averaged 25% across Canada, but some provinces, such as

Ontario, reported wintering losses of 58%.116 In addition, in 2012, Health Canada’s Pest

Management Regulatory Agency (PMRA) began reporting higher bee mortalities associated with

pesticide applications in some areas as part of its pesticide incidents reporting.117

In April 2012, PMRA reported a “significant number of honey bee mortality reports” in the

provinces of Alberta, Manitoba, Saskatchewan, Nova Scotia, Quebec, and Ontario. Most reports

were from southern Ontario, involving more than 40 beekeepers and 240 different locations, with

also one report from Quebec involving eight bee yards. Health Canada concluded “an unusually

high number of reports of honey bee mortalities were received from beekeepers in corn growing

regions of Ontario and Quebec.... Timing and location of these honey bee mortalities appeared to

coincide with planting corn seed treated with insecticides.”118

PMRA’s preliminary findings conclude “there is an indication that pesticides used on treated corn

seeds may have contributed to at least some of the 2012 spring bee losses that occurred in

Ontario.”119 The agency continued to “receive a significant number of pollinator mortality reports

from both corn and soybean growing regions of Ontario and Quebec, as well as Manitoba” in

spring 2013.120 A 2013 field study by researchers at the University of Guelph reported no link

between bee health and pesticide applications.121

Following this investigation, PMRA determined that “current agricultural practices related to the

use of neonicotinoid treated corn and soybean seed are affecting the environment due to their

impacts on bees and other pollinators.”122 The agency implemented measures to reduce honey bee

exposure to dust generated during planting of treated corn seed, including “communication of

best practices to reduce the exposure of honey bees, labelling of treated seed, a treated seed dust

standard, and development of technical solutions to reduce dust, including developments in the

areas of seed coating quality, seed flow lubricants, planting equipment, and disposal of treated

seed bags.”123 For the 2014 planting season, PMRA issued additional protective measures for corn

and soybean production.124 PMRA has continued to re-evaluate nitro-guanidine neonicotinoids to

116

CAPA, “CAPA Statement on Honey Bee Wintering Losses in Canada (2014),” July 2014. Losses in prior years are

available at CAPA’s website, http://www.capabees.com/.

117

See, for example, Health Canada, “2012 Report on Pesticide Incidents,” available at http://www.hc-sc.gc.ca/.

118

Health Canada, “Evaluation of Canadian Bee Mortalities that Coincided with Corn Planting in Spring 2012,”

http://www.hc-sc.gc.ca/cps-spc/pubs/pest/_decisions/bee_corn-mort-abeille_mais/index-eng.php.

119

Health Canada, “Ontario Bee Incidents 2012-Update,” September 2013, http://www.hc-sc.gc.ca/cps-spc/pubs/pest/

_fact-fiche/bees-incidents-abeilles-2012/index-eng.php.

120

Health Canada, “Notice of Intent, NOI2013-01, Action to Protect Bees from Exposure to Neonicotinoid Pesticides,”

September 2013, http://www.hc-sc.gc.ca/cps-spc/pest/part/consultations/_noi2013-01/noi2013-01-eng.php.

121

Presentation by C. Scott-Dupree, “Field Study Reliability: A Honey Bee & Neonicotinoid Perspective,” University

of Guelph, http://sesss08.setac.eu/embed/sesss08/Cynthia_Scott-Dupree_Field_study_Reliability__A_Honey_bee__Neonicotinoid_PERSPECTIVE.pdf.

122

Ibid.

123

Health Canada, “Pollinator Protection: Reducing Risk from Treated Seed,” April 2013, http://www.hc-sc.gc.ca/cpsspc/pubs/pest/_fact-fiche/pollinator-protection-pollinisateurs/index-eng.php.

124

Health Canada, “Notice of Intent, NOI2013-01, Action to Protect Bees from Exposure to Neonicotinoid Pesticides.”

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determine if further regulatory action was needed.125 PMRA is reportedly also planning to

implement label changes similar to those being considered by EPA in the United States (see

“EPA’s New “Bee Advisory” Labeling Requirements”).

In November 2014, the province of Ontario announced a proposal to reduce the use of

neonicotinoid-treated corn and soybean seed (based on acreage of treated seeds planted) by

80%.126 If approved, the new regulations would go into effect by July 1, 2015, prior to the 2016

planting season. Manufacturers of the chemicals claim the decision is not supported by science.

The Canadian industry association, CropLife Canada, is also urging the Canadian government to

broaden its examination of bee population declines beyond pesticides and neonicotinoids.127 The

Canadian government continues to study this issue.128

In September 2014, two large beekeeping operations filed a class-action lawsuit129 on behalf of

Canadian beekeepers against several chemical manufacturers, claiming thiamethoxam (and its

predecessor, imidacloprid) and its breakdown product clothianidin led to more than C$450

million (about US$410 million) in total damages from 2006 to 2013.130 The alleged chronic

effects of the use of these pesticides include “bee deaths; impaired reproduction; immune

suppression; behavioral abnormalities resulting in hive loss; reduced honey production; impacts

on the quality of honey; contamination of hive equipment; loss of queen bees; breeding stock; and

difficulties fulfilling honey product or pollination contracts.” The lawsuit alleges that Bayer and

Syngenta were “negligent in their design and development of the neonicotinoid pesticides,” and

were and continue to be “negligent in their distribution and sale of the neonicotinoid pesticides,”

as well as “negligent in permitting or failing to prevent the damages caused by the neonicotinoids

to the beekeepers.” The plaintiffs further claim that Bayer and Syngenta “knew or ought to have

known that the neonicotinoids would cause damage to the property” of beekeepers, since they

allege that the harm to the beekeepers was “reasonably foreseeable.”

Legal and Other Actions by Some Interest Groups

Selected Actions by Environmental Groups

A number of environmental and food safety advocacy groups, along with individual beekeepers,

have remained active in pressing federal and state authorities on policies and issues pertaining to

125

PMRA, “Re-evaluation Note REV2012-02, Re-evaluation of Neonicotinoid Insecticides,” June 12, 2012,

http://www.hc-sc.gc.ca/cps-spc/pubs/pest/_decisions/index-eng.php.

126

See Ministry of the Environment and Climate Change, “Reducing Pesticide Use and Protecting Pollinator Health

Ontario Sets Goal to Reduce Neonicotinoid Use by 80 Per Cent,” November 25, 2014; and the Ontario Ministry of

Agriculture, Food and Rural Affairs (OMAFRA), “Pollinator Health: A Proposal for Enhancing Pollinator Health and

Reducing the Use of Neonicotinoid Pesticides in Ontario,” November 2014.

127

“Canadian Industry Seeks Broader Approach to Bee Problem,” Food Chemical News, November 15, 2013.

128

See, for example, Environmental Commissioner of Ontario, Managing New Challenges, Annual Report 2013/2014.

129

Sun Parlor Honey Ltd. and Munro Honey v. Bayer CropScience Inc., Bayer Inc., Bayer AG, Syngenta Canada Inc.

and Syngenta International AG, Court File No.: CV-14-21208 (Ontario Superior Court of Justice, Ontario, Canada),

September 2, 2014. The complaint is available at http://www.ontariobee.com/sites/ontariobee.com/files/DOCSLIB%232440628-v1-AMENDED_Claim.pdf.

130

The lawsuit seeks C$400 million (about $370 million) in general and specific damages and C$50 million (about $46

million) in punitive damages, plus interest and legal costs.

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the approval and use of neonicotinoid pesticides, among other agrochemicals. Among these are

the Center for Food Safety (CFS); Earthjustice; Pesticide Action Network North America

(PANNA); Beyond Pesticides; Friends of the Earth; Sierra Club; and the Center for

Environmental Health. These groups have published a series of widely available reports

supporting their policy positions and/or have posted literature reviews on their organization’s

websites, and also have undertaken a series of legal challenges in these matters.131

In March 2013, CFS and a coalition of four beekeepers and five environmental and consumer

groups filed a lawsuit against the EPA to stop the use of pesticides containing clothianidin and

thiamethoxam, which beekeepers in the case claim is damaging the central nervous system of

their bees.132 The lawsuit also challenges EPA’s risk assessment framework for determining

whether pesticides harm pollinators and questions EPA’s approval of certain neonicotinoids. An

opening brief was filed in December 2013 further challenging EPA’s risk assessment framework

and requesting that the court reverse EPA’s decision to register sulfoxaflor.133 In July 2014, CFS,

Earthjustice, PANNA, and Beyond Pesticides challenged California’s approval of new

agricultural uses for two neonicotinoid pesticides, Venom Insecticide and Dinotefuran 20SG.134

Previously, in 2005, two beekeepers residing in Minnesota sued the state’s Department of Natural

Resources for losses incurred from spraying of a pesticide, carbaryl. In that case, the pesticide

users reportedly offered to settle, and the state’s Department of Natural Resources stopped using

the pesticide.135

These legal challenges follow previous requests for EPA to restrict the use of certain pesticides. In

a March 2012 citizen petition, CFS and a coalition of beekeepers along with PANNA filed an

“Emergency Petition” with EPA asking for a suspension of the use of clothianidin until it is

proven safe to pollinators and the environment.136 EPA responded in part to the petition in July

2012.137 A few weeks later, EPA announced that it was denying the request to suspend

131

For example, CFS, “Heavy Costs: Weighing the Value of Neonicotinoid Insecticides in Agriculture” (March 2014)

and “Pollinators & Pesticides” (September 2013); PANNA, “Honey Bees and Pesticides: State of the Science” (May

2012); and Friends of the Earth, “Follow the Honey” (April 2014) and “Gardeners Beware” (October 2013, June 2014).

132

Steve Ellis, Tom Theobald, Jim Doan, Bill Rhodes, CFS, et al. v. Steven P. Bradbury and Bob Perciasepe, U.S.

Environmental Protection Agency, Case No. 3:13-Cv-01266-Lb (U.S. District Court for the Northern District of

California, San Francisco Division), May 31, 2013. In addition to CFS, the coalition is represented by Beyond

Pesticides, Pesticide PANNA, Sierra Club, and the Center for Environmental Health, as well as four beekeepers with

operations located in California, Colorado, Florida, New York, and Minnesota. The amended complaint is at

http://www.centerforfoodsafety.org/issues/304/pollinators-and-pesticides/legal-actions. For more information, see CFS,

“CFS, Beekeepers and Public Interest Groups Sue EPA over Bee-Toxic Pesticides,” March 21, 2013,

http://www.centerforfoodsafety.org/issues/304/pollinators-and-pesticides/press-releases.

133

Pollinator Stewardship Council et al. v. USEPA and Dow Agrosciences, Case No.13-72346 (U.S. Court of Appeals

for the 9th Circuit), December 13, 2013. The amicus curiae brief is at http://www.centerforfoodsafety.org/issues/304/

pollinators-and-pesticides/legal-actions.

134

PANNA, CFS, and Beyond Pesticides v. California Department of Pesticide Regulation et al., Case No.

RG14731906 (Superior Court for the State of California for the County of Alameda), July 8, 2014. The original

complaint is at http://www.centerforfoodsafety.org/issues/304/pollinators-and-pesticides/legal-actions.

135

Jeffrey Anderson, et al., v. State of Minnesota, Department of Natural Resources, A03-679 (State of Minnesota in

Supreme Court), March 3, 2005 (posted: http://www.beyondpesticides.org/documents/MNSUPREME_Decision.pdf).

136

Emergency Citizen Petition to the United States Environmental Protection Agency, March 12, 2013

http://www.centerforfoodsafety.org/files/cfs-clothianidin-petition-3-20-12_57213.pdf.

137

EPA’s response: S. P. Bradbury, EPA Office of Pesticide Programs, letter to Peter T. Jenkins, Center for Food

Safety and International Center for Technology Assessment, “Clothianidin Emergency Citizen Petition dated March 20,

2012,” July 17, 2012. The petition and numerous supplemental submissions of research reports and opinions are posted

(continued...)

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registrations “to prevent imminent harm” because the petitioners did not meet the burden of proof

for registration suspension.138 However, EPA received public comments on this decision and may

revisit its decision as it reviews neonicotinoid registrations. Again, in July 2014, NRDC

petitioned EPA to conduct an emergency review of the impacts of neonicotinoid pesticides on

bees, and to complete its review within one year.139 For more information, see “EPA’s Pesticide

Registration Review of Neonicotinoid Pesticides.”

In June 2013, a coalition of advocacy groups, including CFS, sent a letter to President Obama

asking him to order EPA to ban use of neonicotinoid insecticides for at least two years.140 The

letter asserts that the registration process lacks consideration of pesticide effects on colonies and

focuses exclusively on acute mortality, rather than on sublethal effects of repeated exposure.

Another letter followed in January 2015 from commercial beekeepers, environmental groups, and

some food businesses, who continue to push for restrictions on pesticide use.141

Selected Actions by Agrochemical Companies

Some major agrochemical companies—in particular, Syngenta AG (a global Swiss agribusiness

company) and Bayer AG (a global German company)—have been actively engaged in defending

the use of neonicotinoid pesticides, among other agrochemicals, and claim there is no evidence to

support a systematic correlation between honey bee colony mortality and the use of

neonicotinoids.142 Bayer’s bee care pamphlet claims “poor bee health is correlated with the

presence of Varroa, a parasitic mite, viruses and many other factors, but not with the use of

insecticides.”143 These companies and other industry groups, as well as the trade association

CropLife Amercia,144 have published commissioned reports supporting their policy positions,145

and have supported various pollinator health146 as well as lobbying efforts.147

(...continued)

in the regulatory docket (docket: EPA-HQ-OPP-2012-0334-0015).

138

77 Federal Register 145: 44233-44234, July 27, 2012. Other information is in the regulatory docket (docket: EPAHQ-OPP-2012-0334).

139

NRDC, “Petition for Interim Administrative Review of Neonicotinoid Pesticides,” filed July 7, 2014,

http://docs.nrdc.org/health/files/hea_14070701a.pdf.

140

The June 20, 2013, letter is available at http://www.centerforfoodsafety.org/files/final-neonic-letter62013_43430.pdf. Also see P. Ambrosio, “Environmental Groups Urge President to Ban Neonicotinoids over Threat to

Bees,” Bloomberg BNA Daily Environment Report, June 24, 2013.

141

See, for example, letter to U.S. President Barack Obama from more than 100 environmentally friendly food

companies urging the Administration to protect bees and other pollinators from pesticides, January 13, 2015.

142

“Crop Protection Industry Plans Response to EPA on Neonicotinoids,” Agri-Pulse, October 29, 2014.

143

Bayer pamphlet, “Honey Bee Health: Understanding the Issues, Providing Solutions.”

144

CropLife represents “companies that develop, manufacture, formulate and distribute crop protection chemicals and

plant science solutions for agriculture and pest management” including Syngenta, Bayer, Dow, Dupont, and Monsanto.

145

See, for example, Ag Infomatics, “Value of Neonicotinoids in North American Agriculture” (October 2014); and

CropLife Foundation, “The Role of Seed Treatment in Modern U.S. Crop Production” (December 2013).

146

For example: Bayer’s “Bee Care Center” in North Carolina; Syngenta’s funding of research grants to study causes

of pollinator declines; and Monsanto’s purchase in 2011 of the Beeologics research organization in Missouri.

147

See, for example, postings by Corporate Europe Observatory, “Pesticides Against Pollinators: Private Letters Reveal

Syngenta and Bayer’s Furious Lobbying Against EU Measures to Save Bees,” April 11, 2013,

http://corporateeurope.org/agribusiness/2013/04/pesticides-against-pollinators.

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According to news reports, both Syngenta and Bayer are legally challenging the EU’s

neonicotinoid ban.148 Syngenta claims these pesticides are not responsible for the pollinator

population declines, which they claim are instead the result of disease, viruses, habitat loss, and

poor nutrition.149 According to reports, Syngenta wants to reverse the EU ban but also wants to be

compensated for damages and “defend our reputation which has been significantly damaged.”150

Syngenta claims the EU’s decision to ban the pesticides is based on “a flawed process, an

inaccurate and incomplete assessment by the European Food Safety Authority and without the

full support of EU Member States.”151

Syngenta also has petitioned EPA to increase the allowable threshold for residues of

thiamethoxam. EPA published its proposal in September 2014.152

Congressional Consideration

Given continued concerns about the health and well-being of honey bees and other pollinators,

this issue has continued to be legislatively active. The 2014 farm bill (P.L. 113-79) reauthorized

and expanded provisions supporting research on honey bees and other pollinators that were

enacted in the 2008 farm bill. In previous Congresses, bills were introduced to promote and

improve habitat for honey bees and wild bees, among other pollinators.153 Still other introduced

legislation would address a range of pesticide issues affecting pollinators. Over the past few

years, Congress has conducted hearings on this issue154 and hosted a series of congressional

briefings to discuss these and related issues representing a broad range of interested groups.155

For the 114th Congress, Representative Rodney Davis, the incoming chairman of the House

Agriculture Subcommittee on Biotechnology, Horticulture, and Research, is quoted as saying that

bee health will be a top issue for his subcommittee.156

148

T. Rabesandratana, “Pesticidemakers Challenge E.U. Neonicotinoid Ban in Court,” Science, August 28, 2013,

http://news.sciencemag.org/europe/2013/08/pesticidemakers-challenge-e.u.-neonicotinoid-ban-court.

149

Syngenta, “Syngenta Submits Legal Challenge to EU Suspension of Thiamethoxam,” August 27, 2013,

http://www.syngenta.com/global/corporate/en/news-center/news-releases/Pages/130827.aspx.

150

T. Rabesandratana, “Pesticidemakers Challenge E.U. Neonicotinoid Ban in Court,” Science, August 28, 2013,

http://news.sciencemag.org/europe/2013/08/pesticidemakers-challenge-e.u.-neonicotinoid-ban-court.

151

Syngenta, “Syngenta Submits Legal Challenge to EU Suspension of Thiamethoxam,” August 27, 2013,

http://www.syngenta.com/global/corporate/en/news-center/news-releases/Pages/130827.aspx.

152

79 Federal Register 172: 53009: September 5, 2014. For more information, see “EPA’s Consideration to Modify

Thiamethoxam Tolerance Levels.”

153

For more information, see CRS Report R43191, Bee Health: Background and Issues for Congress.

154

See, for example, “Subcommittee Examines Research Efforts to Combat Pests and Diseases of Pollinators,” House

Agriculture Subcommittee on Horticulture, Research, Biotechnology, and Foreign Agriculture hearing, April 29, 2014.

155

For example: “Impacts of Pesticides on Birds, Bees, and Broader Ecosystems” (March 2013); “Honey Bee Colony

Health” (April 2013); “Applied Bee-Nomics” (June 2013); “What’s Killing Our Bees?” (October 2013, December

2013); and “The Threat of Neonicotinoid Pesticides to Bees and Other Organism, and Risks to Human Health”

(September 2014).

156

T. Stecker, “New House Subcommittee Chief Will Push Forward on Bee Issues,” Environmental and Energy Policy,

December 16, 2014.

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Saving America’s Pollinators Act

In the 113th Congress, Representatives Earl Blumenauer and John Conyers Jr. introduced H.R.

2692, the Saving America’s Pollinators Act of 2013. The bill would have suspended registrations

of neonicotinoids and banned new registrations of any pesticide for use on “bee attractive plants,

trees, and cereals.” This bill was initially introduced, in part, as a response to reports that 50,000

bees were found dead in a suburban shopping-center parking lot in Wilsonville, Oregon, in June

2013, reportedly due to exposure to pesticides used on trees near the parking lot to control

aphids.157

Specifically, the bill would have required EPA to “suspend the registration of imidacloprid,

clothianidin, thiamethoxam, dinotafuran, and any other members of the nitro group of

neonicotinoid insecticides to the extent such insecticide is registered, conditionally or otherwise,”

under FIFRA (7 U.S.C. 136 et seq.) “for use in seed treatment, soil application, or foliar treatment

on bee attractive plants, trees, and cereals.”

These suspensions on existing registrations and restrictions on new registrations would remain

until more research is conducted and EPA determines that the insecticide will not cause

“unreasonable adverse effects” on pollinators, including honey bees, native bees, and other

pollinators. Such an assessment would be based on an evaluation of the published and peerreviewed scientific evidence and a completed field study. The bill also would have required the

Department of the Interior to coordinate with EPA in monitoring the health and populations of

native bees, and annually report to Congress on their health and population status.

H.R. 2692 was similar to proposals being implemented or considered in the EU and Canada. In

particular, the bill’s language regarding “bee attractive plants, trees, and cereals” is similar to that

under the EU’s ban of the use of three neonicotinoid pesticides—clothianidin, imidacloprid and

thiamethoxam—for “seed treatment, soil application (granules) and foliar treatment on bee

attractive plants and cereals.”158 However, the EU’s restrictions provide for certain exceptions

(such as greenhouses and open-air fields after flowering), which are not provided for in H.R.

2692. (See “Restrictions in the European Union” for additional information on the EU’s ban.)

In September 2014, the sponsors of H.R. 2692, along with 58 other Members of the U.S. House

of Representatives, sent a letter to EPA urging the agency to “restrict and/or suspend the use of

neonicotinoids on bee-attractive crops and ornamental application,” including restricting the

“times, methods of application, and location” for use of these pesticides, as well as urging EPA to

review its policies related to EPA’s pesticide registration, among other recommendations.159 EPA

received a similar letter from many environmental and sustainable agriculture organizations,

including CFS, Friends of the Earth, Food and Water Watch, and other groups.160

157

See, for example, press release on the bill by Representative Earl Blumenauer’s office.

Regulation (EC) No 485/2013 of 24 May 2013 amending Implementing Regulation (EU) No 540/2011, as regards

the conditions of approval of the active substances clothianidin, thiamethoxam and imidacloprid, and prohibiting the

use and sale of seeds treated with plant protection products containing those active substances.

159

Letter to EPA Administrator Gina McCarthy from Representatives Earl Blumenauer and John Conyers and 58 other

House of Representatives Members, September 30, 2014.

160

Letter to EPA Administrator Gina McCarthy from Representatives Earl Blumenauer and John Conyers and 58 other

House of Representatives Members, September 24, 2014.

158

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Groups opposed to restrictions on pesticide use contend that comprehensive studies “challenge

unsubstantiated claims against pesticides as a significant cause of colony decline” and note that

“infrequent accidental exposures are not indicative of the general health of honey bee

colonies.”161 Some further claim “there is no evidence linking neonicotinoids to bee declines” or

to adverse health effects on bees.162 They generally challenge studies that target neonicotinoids as

the sole factor contributing to pollinator declines, and further maintain that unwanted pesticide

exposure may be best addressed through “effective product labeling and the implementation of

meaningful stewardship actions that help minimize harmful interactions.”163 Others question

whether crop-applied pesticides pose a major risk to bees, given current approved uses and

beekeeping practices.164

Expedited Pesticide Registration for Managing Parasitic Pests

In the 113th Congress, Representative Austin Scott introduced H.R. 5447, which would have

amended U.S. pesticide laws (FIFRA; 7 U.S.C. 136a(c)(10)) to provide for expedited registration

of pesticides that “improve managed pollinator bee health, including managing resistance to

parasitic pests” and for expedited review of a pesticide registration that is “reasonably expected to

improve the health of managed pollinator bees, including managing resistance to parasitic pests of

managed pollinator bees,” such as miticides. H.R. 5447 would have also required reports to

Congress from both USDA and EPA. The report required from USDA would address the “extent

and scope of the threat to the health of managed pollinator bees” from pathological factors (such

as the parasitic mite, Varroa destructor; other arthropod pests; and fungal, microbial, and viral

diseases) and from environmental factors (including habitat, forage, beekeeper practices and

husbandry, and nutritional needs of managed bees). The report required by EPA would address the

availability of pesticides to manage parasites and also EPA’s efforts to expedite approvals of new

products to control parasites of managed bees. The bill would have defined “managed pollinator

bee” to mean “any bee that is raised and housed in a managed hive or other appropriate housing

and used for honey production, managed pollination of crops, or breeding for commercial

purposes.” The bill was supported by some U.S. crop producers and other industry groups.

Some advocacy groups were opposed to H.R. 5447 and contend that “fast-tracking pesticide

approvals” has contributed to current concerns involving bees and pesticides.165 They further

complain that focusing attention on other factors contributing to bee declines (such as mites)

tends to shift attention away from remedies that could address beekeeper concerns about pesticide

exposure, such as instituting agricultural best management practices (BMPs) that might avoid

application of insecticides during bloom, and minimize exposure to bees by avoiding applications

when pollen is available and bees are feeding.166

161

Testimony of David Fischer, Bayer North American Bee Care Center, at a House Agriculture Subcommittee on

Horticulture, Research, Biotechnology, and Foreign Agriculture hearing, April 29, 2014.

162

Statements by CropLife representatives reported by J. R. Pegg, “Groups Press EPA, California to Protect Bees from

Neonicotinoids,” Food Chemical News, July 14, 2014; also written correspondence from David Fischer, Bayer

CropScience LP, to members of the North American Pollinator Protection Campaign (NAPPC), November 18, 2014.

163

Testimony of David Fischer, Bayer North American Bee Care Center, at a House Agriculture Subcommittee on

Horticulture, Research, Biotechnology, and Foreign Agriculture hearing, April 29, 2014.

164

See, for example, A Fairbrother et al., “Risks of Neonicotinoid Insecticides to Honeybees,” Environmental

Toxicology and Chemistry, vol. 33, no. 4 (April 2014).

165

CFS press release, “New Pollinator Bill Helps Pesticide Industry, Not Bees or Beekeepers,” September 12, 2014.

166

Pollinator Stewardship Council, “House Subcommittee Forgot to Ask Beekeeping Industry,” May 2, 2014.

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In February 2015, EPA announced its intentions to fast track approval of oxalic acid dihydrate for

use as a miticide in beehives.167 Oxalic acid has been used against varroa mites and is generally

considered more safe compared to other higher risk chemicals. It has been approved for use in

Canada since 2010, where a government analysis there claims: “An evaluation of available

scientific information found that under the approved conditions of use the product has value and

does not present an unacceptable risk to human health or the environment.”168

167

168

80 Federal Register 23: 6084-6085, February 4, 2015.

Canadian Honey Council, “Oxalic Acid,” http://www.honeycouncil.ca/oxalic_acid.php.

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Appendix. Review of the Scientific Literature169

Following is a summary of selected scientific literature based largely on publications in peerreviewed journals.

Bee Exposure to Pesticides

Researchers at USDA and others found that “high levels” of fungicides were present in both crop

and non-crop pollen collected by bees, and that “real world pollen-pesticide blends affect honey

bee health.”170 These scientists found very high levels of the fungicide chlorothalonil in pollen

and wax,171 and found high levels of at least four insecticides, three other fungicides, and an

herbicide. Chlorothalonil and the two miticides, fluvalinate and coumaphos, were most frequently

detected in pollen and wax. A 2010 study tested samples of beebread,172 trapped pollen,173 brood

nest wax,174 beeswax foundation,175 and adult bees and brood and found a broad range of

pesticides, including acaricides (which kill arachnids like spiders, ticks, and mites), fungicides,

insecticides, and herbicides.176

Bees can be exposed to neonicotinoids in many ways. One study identified multiple routes of

exposure to low levels of neonicotinoids for honey bees living and foraging near agricultural

fields planted with corn or soybeans.177 The highest potential exposure to the pesticides appeared

to occur during planting season, when bee mortality was also high. Clothianidin was found in

about half the bee-collected pollen sampled, thiamethoxam (which is quickly metabolized to

become clothianidin) in 3 of 20 samples, and fungicides in all pollen samples. Levels of

clothianidin in some pollen were high enough to kill bees. Clothianidin was detected in all dead

and dying bees but in no healthy bees. Although corn is not an insect-pollinated crop, this

research demonstrated that bees forage for corn pollen and take it back to the hive. About half the

hive pollen sampled came from corn in this study. In addition, the study documented high levels

of pesticide in exhaust material from mechanical planters when pesticides and talc were used to

coat seeds, and found clothianidin in soil samples from planted and unplanted fields.

169

This section was originally prepared by CRS Analyst, Linda J. Schierow, now retired.

J. Pettis, E. Lichtenberg, M. Andree, et al., “Crop Pollination Exposes Honey Bees to Pesticides Which Alters Their

Susceptibility to the Gut Pathogen Nosema ceranae,” PLoS ONE, v. 8. n. 7 (2013), p. e70182.

171

Fungicides typically are applied to blooming plants which may be visited by bees. Labels on fungicides recommend

such application for control of certain pests.

172

Beebread is a pollen mixture stored in honeycomb cells and used with honey by bees as food. Beebread provides

nutrition for the queen and brood.

173

Trapped pollen refers to pollen collected at the entrance to the hive, removed from bees with the use of a trap.

174

This is wax originating in the area of the hive where brood is reared.

175

Foundation is the hexagonal sheets of wax and or wax/plastic combination that serves as a basis for comb

construction by honey bees.

176

C. A. Mullin, M. Frazier, J. L. Frazier, et al., “High Levels of Miticides and Agrochemicals in North American

Apiaries: Implications for Honey Bee Health,” PLoS ONE, v. 5, n. 3 (2010), p. e9754.

177

C. Krupke, G. Hunt, B. Eitzer, et al., “Multiple Routes of Pesticide Exposure for Honey Bees Living near

Agricultural Fields,” PLoS ONE, v. 7, n. 1 (2012), p. e29268.

170

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Other studies have measured neonicotinoids in pollen and nectar of canola (rape seed),178 corn,179

and sunflowers180 grown from seed coated with pesticides. Levels found were below those known

to be acutely toxic. Other studies have found that imidacloprid and thiamethoxam concentrations

in nectar were greater in squash181 and pumpkin flowers182 when insecticide was applied to the

soil than they were in canola and sunflowers grown from seed treated with neonicotinoids.

Researchers also found metabolites of imidacloprid and thiamethoxam (clothianidin) in all parts

of squash plants, along with the parent compound.183

A 2012 study found levels of neonicotinoids in bee-collected corn pollen that were similar to

levels of imidacloprid determined by other scientists to have sublethal effects potentially affecting

colony health.184 Similarly, a subsequent study in 2013 found that imidacloprid levels in pollen

gathered from bees in the field were high enough to cause sublethal effects on honey bees and

bumble bees, based on laboratory research.185 A 2013 study by the European Food Safety Agency

(EFSA) of three neonicotinoid pesticides—imidacloprid, clothianidin, and thiamethoxam—

determined that bees faced several risks including exposure to pollen and nectar, dust, and

guttation fluid from maize.186

Another potential source of exposure was suggested by another 2012 study, showing that bees

might be exposed to neonicotinoids in the corn syrup they are sometimes fed during the winter by

178

G. C. Cutler and C. D. Scott-Dupree, “Exposure to Clothianidin Seed-Treated Canola Has No Long-Term Impact on

Honey Bees,” Journal of Economic Entomology, v. 100 (2007), pp. 765-772.

179

J. M. Bonmatin, P. A. Marchand, R. Cahvet, et al., “Quantification of Imidacloprid Uptake in Maize Crops,”

Journal of Agricultural and Food Chemistry, v. 53 (2005), pp. 5336-5341; and C. Krupke, G. Hunt, B. Eitzer, et al.,

“Multiple Routes of Pesticide Exposure for Honey Bees Living near Agricultural Fields,” PLoS ONE, v. 7, n. 1 (2012),

p. e29268.

180

F. M. Laurent and E. Rathahao, “Distribution of [14C] Imidacloprid in Sunflowers (Helianthus annuus L.) Following

Seed Treatment,” Journal of Agricultural and Food Chemistry, v. 51 (2003), pp. 8005-8010; R. Schmuck, R. Schoning, A.

Stork, et al., “Risk Posed to Honeybees (Apis mellifera L, Hymenoptera) by an Imidacloprid Seed Dressing of Sunflowers,”

Pest Management Science, v. 57 (2001), pp. 225-238.

181

K A. Stoner and B. D. Eitzer, “Movement of Soil-Applied Imidacloprid and Thiamethoxam into Nectar and Pollen

of Squash (Cucurbita pepo),” PLoS ONE, v. 7, n. 6 (2012), p. e39114.

182

G. P. Dively and A. Kamel, “Insecticide Residues in Pollen and Nectar of a Cucurbit Crop and Their Potential

Exposure to Pollinators,” Journal of Agricultural and Food Chemistry, v. 60 (2012), pp. 4449-4456.

183

K. A. Stoner and B. D. Eitzer, “Movement of Soil-Applied Imidacloprid and Thiamethoxam into Nectar and Pollen

of Squash (Cucurbita pepo),” PLoS ONE, v. 7, n. 6 (2012), p. e39114.

184

C. Krupke, G. Hunt, B. Eitzer, et al., “Multiple Routes of Pesticide Exposure for Honey Bees Living near

Agricultural Fields,” PLoS ONE, v. 7, n. 1 (2012), p. e29268. The study references other studies with similar findings,

including H. V. V. Tomé, G. F. Martins, M. August, et al., “Imidacloprid-Induced Impairment of Mushroom Bodies

and Behavior of the Native Stingless Bee Melipona quadrifasciata anthidioides,” PLoS ONE, v. 7, n. 6 (2012), p.

e38406; D. M. Eiri and J. C. Nieh, “A Nicotinic Cacetylcholine Receptor Agonist Affects Honey Bee Sucrose

Responsiveness and Decreases Waggle Dancing,” Journal of Experimental Biology, v. 215, n. 12 (2012), pp. 20222029; A. Decourtye, E. Lacassie, and M. Pham-Delegue, “Learning Performances of Honey Bees (Apis mellifera L.)

Are Differentially Affected by Imidacloprid According to the Season,” Pest Management Science, v. 59 (2003), pp.

269-278; or V. Mommaerts, S. Reynders, J. Boulet, et al., “Risk Assessment for Side-Effects of Neonicotinoids Against

Bumblebees with and Without Impairing Foraging Behavior,” Ecotoxicology, v. 19 (2010), pp. 207-215.

185

J. Pettis, E. Lichtenberg, M. Andree, et al., “Crop Pollination Exposes Honey Bees to Pesticides Which Alters Their

Susceptibility to the Gut Pathogen Nosema ceranae, PLoS ONE, v. 8. n. 7 (2013), p. e70182; P. R. Whitehorn, S.

O’Connor, F. L. Wackers, et al., “Neonicotinoid Pestide Reduces Bumble Bee Colony Growth and Queen Production,”

Science, v. 336 (2012), pp. 351-352; and T. Blacquiere, G. Smagghe, C. A. M. van Gestel, et al., “Neonicotinoids in

Bees: A Review on Centrations, Side-Effects and Risk Assessment, Ecootoxicology, v. 21 (2012), pp. 973-992.

186

EFSA press release, “EFSA Press Release: EFSA Identifies Risks to Bees from Neonicotinoids,” January 16, 2013.

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Bee Health: The Role of Pesticides

beekeepers.187 However, the researchers did not sample corn syrup actually fed to bees, but rather

showed that bees would consume sufficient imidacloprid to produce toxic sublethal effects if they

were provided contaminated corn syrup in the hive. Other research found no pesticides in samples

of high-fructose corn syrup obtained from three major suppliers.188

Pesticide Effects on Bee Health

According to research cited in a 2007 study by the National Research Council (NRC), “the

application of pesticides, especially insecticides used to control crop pests, kills or weakens

thousands of honey bee colonies in the United States each year.”189 Nevertheless, the study

concluded that local bee kills “likely have not contributed significantly to the recent national

decline in colony populations” [emphasis added].190

Recent studies have begun to identify mechanisms by which some chemical interactions occur.191

For example, some fungicides may inhibit an enzyme that bees need to detoxify miticides.192

However, further research is needed since measurement difficulties continue to complicate study

of this issue, including difficulty testing the in-field or field-realistic doses; effects at different life

stages; how to account for cases of accidental exposure or exposure to multiple different types of

pesticides; and how to account for species diversity (e.g., between honey bees and native bees),

differences in nutritional needs/access and nesting sites, biological organization, and floral

specialization.193

Generalizations about the relative importance of pesticides for global bee health cannot be drawn

from available data, given the disparate study designs and results. Moreover, research has been

and continues to be conducted, with most scientists focusing on a single pesticide or pathogen at a

time. Consideration of interactions has been minimal—whether exposure from different types of

chemicals or exposure from chemicals in combination with other factors. One study explains:

Attempts to correlate global bee declines or CCD with increased pesticide exposures alone, have

not been successful to date.… Pesticide interactions among various mixtures as well as with other

stressors including Varroa and Nosema, IAPV, beneficial hive microbes, and impacts on bee

immune systems all require further study. It seems to us that it is far too early to attempt to link or

to dismiss pesticide impacts with CCD.194

187

Chensheng Lu, K. M. Warchol, and R. A. Callahan, “In Situ Replication of Honey Bee Colony Collapse Disorder,”

Bulletin of Insectology, v. 65, n. 1 (March 2012), pp. 99-106.

188

G. DeGrandi-Hoffman, D. Sammataro, and R. Simonds, “Are Agrochemicals Present in High Fructose Corn Syrup Fed

to Honey Bees (Apis mellifera L.)?” Journal of Apicultural Research, v. 51, n. 4 (2012), pp. 371-372.

189

C. A. Johansen and D. F. Mayer, 1990, Pollinator Protection, A Bee and Pesticide Handbook.

190

2007 NRC study, p. 79.

191

W. Mao, M. A. Schuler, and M. R. Berenbaum, “CYP9Q-Mediated Detoxification of Acaricides in the Honey Bee

(Apis mellifera),” Proceedings of the National Academy of Sciences of the United States of America, v. 108, n. 31

(2011), pp. 12657-12662; and R. M. Johnson, H. S. Pollock, and M. R. Berenbaum, “Synergistic Interactions Between

In-Hive Miticides in Apis mellifera,” Journal of Exonomic Entomology, v. 102, n. 2 (2009), pp. 474-479.

192

R. M. Johnson, L. Dahlgren, B. D. Siegfried, et al., “Acaricide, Fungicide and Drug Interactions in Honey Bees

(Apis mellifera),” PLoS ONE, v. 8, n. 1 (2013), p. e54092.

193

T. Blacquiere, et al., “Neonicotinoids in Bees: A Review on Concentration, Side-Effects and Risk Assessment,”

Ecotoxicology, vol. 21 (2012), pp. 973-992; and also comments by Nathalie Steinhauer (University of Maryland) to the

Virginia Native Plant Society, October 9, 2014.

194

C. A. Mullin, M. Frazier, J. L. Frazier, et al., “High Levels of Miticides and Agrochemicals in North American

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The study noted that the doses of individual pesticides found in bees were not concentrated

enough to be lethal, but the authors remained concerned about possible chronic problems caused

by long-term exposure and possible additive or synergistic effects of exposure to the

combinations of pesticides found.195 For example, numerous pesticides classified as pyrethroids

that were found in the field have been shown to cause disorientation in honey bees.196

It is important to note that virtually all information about pesticide risks to bees derives from

studies in cultivated fields or laboratories. There is little or no information about the possible

impacts on bee populations of pesticides applied by homeowners (for example, to control

mosquitos) or to ornamental plantings.

Nevertheless, a sizeable and growing body of scientific research presents compelling evidence

suggesting that pesticide exposure may be harmful to bees and other animal species. For example,

a 2014 meta-analysis covering 800 peer-reviewed reports over two decades examined the

reported effects of systemic pesticides on ecosystems and a range of animal species—terrestrial

invertebrates, including insect pollinators; aquatic invertebrates; and birds.197 The analysis,

conducted by entomologists and ornithologists based in Europe, concluded that neonicotinoid

pesticides “pose a serious risk to honeybees and other pollinators such as butterflies and to a wide

range of other invertebrates such as earthworms and vertebrates including birds.”198

In response to reports that honey bees are disappearing and causing hives to collapse, recent

studies of the impacts of exposure to imidacloprid and other neonicotinoids199 have focused more

on their potential to affect complex behaviors in insects, including flight, navigation, olfactory

memory, recruitment, foraging, and coordination.200 One study reported sublethal effects of

neonicotinoid pesticides on honey bee foraging behavior that may impair the navigational and

foraging abilities of honey bees.201 Another study found a reduction of foraging activity and

(...continued)

Apiaries: Implications for Honey Bee Health,” PLoS ONE, v. 5, n. 3 (2010), p. e9754.

195

C. A. Mullin, M. Frazier, J. L. Frazier, et al., “High Levels of Miticides and Agrochemicals in North American

Apiaries: Implications for Honey Bee Health,” PLoS ONE, v. 5, n. 3 (2010), p. e9754.

196

H. Thompson and S. Wilkins, “Assessment of the Synergy and Repellency of Pyrethroid/Fungicide Mixtures,”

Bulletin of Insectology, v. 56 (2003), pp. 131-0134; and R. L. Cox and W. T. Wilson, “Effects of Permethrin on the

Behavior of Individually Tagged Honey Bees, Apis mellifera L. (Hymenooptera, Apidae),” Environmental Entomology,

v. 13 (1984), pp. 375-378.

197

Findings of the task force (which is affiliated with the International Union for Conservation of Nature) are at

http://www.tfsp.info. The published study is M. B. van Lexmond, et al., “Worldwide Integrated Assessment on

Systemic Pesticides,” Environ Sci Pollut Res, August 2014. See also M. Chagnon and D. Kreutzweiser, et al., “Risks of

Large-Scale Use of Systemic Insecticides to Ecosystem Functioning and Services,” Environ. Sci. Pollut. Res., July

2014. See also D. Gibbons, C. Morrisey, P. Mineau, “A Review of the Direct and Indirect Effects of Nenicotinoids and

Fipronil on Vertebrate Wildlife,” Environ. Sci. Pollut. Res., June 2014.

198

Press release, “Systemic Pesticides Pose Global Threat to Biodiversity and Ecosystem Services,” June 24, 2014.

199

D. Cox-Foster and D. vanEngelsdorp, “Solving the Mystery of the Vanishing Bees,” Scientific American, March 31,

2009; Northwest Coalition for Alternatives to Pesticides, “Imidacloprid, Fact Sheet,” Journal of Pesticide Reform,

Spring 2001 (http://www.pesticide.org/imidacloprid.pdf); and Apiculteurs de France, “Composite Document of Present

Position Relating to Gaucho, Sunflower and Bees” (http://www.beekeeping.com/articles/us/gaucho/

manifestation_paris_us.htm). See also J. Cummins, “Neonicotinoid Insecticides Used in Seed Dressing May Be

Responsible for the Collapse of Honeybee Colonies,” Institute of Science in Society, April 24, 2007.

200

BNA’s International Environmental Law Committee Newsletter, vol. 11, no. 1, February 2009.

201

M. Henry, M. Beguin, F. Requier, et al., “A Common Pesticide Decreases Foraging Success and Survival in Honey

Bees,” Science, v. 336, n. 6079 (2012), pp. 348-350; and K. A. Stoner and B. D. Eitzer, “Movement of Soil-Applied

Imidacloprid and Thiamethoxam into Nectar and Pollen of Squash (Cucurbita pepo),” PLoS ONE, v. 7, n. 6 (2012), p.

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Bee Health: The Role of Pesticides

homing behavior of honey bees exposed to treated crops at certain exposure levels of

neonicotinoids.202

Scientists at Bayer Crop Science argue with the findings of these and other studies, claiming that

the dose of pesticide delivered to bees in some studies is not “field-relevant,” resulting in findings

obtained “under artificial conditions” and “in conflict with” earlier studies.203 Some of the

statements made in the 2012 Bayer Crop Science review of the scientific literature have been

rebutted by researchers at Purdue University and Pennsylvania State University, based on

comments submitted by the Center for Food Safety as part of EPA’s public rulemaking docket.204

Among a list of concerns regarding various statements in the Bayer Crop Science report,

Professor Frazier from Pennsylvania State University states: “To object to a specific dose on the

basis of an estimated level without giving the reader the actual basis for this neglects not only

good science protocol, but also obfuscates any arguments.”205 Among other comments, Professor

Krupke from Purdue University further acknowledges: “These data suggest that there is a strong

likelihood that the neonicotinoids thiamethoxam and/or clothianidin were responsible for the bee

kills we investigated.”206

EPA has determined that clothianidin “has the potential to be highly toxic on both a contact and

an oral basis” to honey bees.207 EPA also has reported that one honey bee field study submitted to

the agency indicates that “mortality, pollen foraging activity, and honey yield were negatively

affected by residues of clothianidin,” but the residue levels causing the effect were not reported.

Acute effects also have been demonstrated in another field study. It showed that honey bees can

be killed by exposure to pesticide-contaminated talc if they fly through dust clouds associated

with planting,208 but mortality appears to depend on high levels of humidity.209 Health Canada has

concluded that corn planting also was implicated in bee mortalities in Ontario during the spring

planting season in 2012.210

(...continued)

e39114.

202

C.W. Schneider, J. Tautz, B. Grünewald, et al., “RFID Tracking of Sublethal Effects of Two Neonicotinoid

Insecticides on the Foraging Behavior of Apis mellifera.” PLoS ONE, v. 7, n. 1 (2012), p. e30023.

203

Bayer Crop Science, “Overview of Recent Publications on Neonicotinoids and Pollinators.” Paper was prepared by

Richard Heintzelman, Iain D. Kelly, David L. Fischer, and Christian Maus, May 23, 2012 (referred to here as

Heintzelman et al.). Paper was submitted to CRS from Jean Reimers (CropLife America), June 20, 2012.

204

Opinions submitted by Christian Krupke (Purdue University) and James Frazier (Pennsylvania State University) in

response to a review of publications on neonicotinoids and pollinators prepared by Heintzelman et al. (May 23, 2012).

These comments are contained within Appendix A and Appendix B, respectively, as part of public comments submitted

to EPA by the Center for Food Safety (docket: EPA-HQ-OPP-2012-0334). The Center for Food Safety’s own review of

the scientific literature is titled “Pollinators and Pesticides,” 2013.

205

Ibid. Appendix B, “Opinion of Prof. James Frazier,” June 14, 2012.

206

Ibid. Appendix A, “Opinion of Prof. Christian Krupke,” June 7, 2012.

207

J. DeCant and M. Barrett, 2010, “Environmental Fate and Ecological Risk Assessment for the Registration of

Clothianidin for Use as a Seed Treatment on Mustard Seed (Oilseed and Condiment) and Cotton,” EPA/Office of

Prevention, Pesticides and Toxic Substances, Office of Pesticide Programs, Washington, DC, p. 14.

208

A. Tapparo, D. Marton, C. Giorio, et al., “Assessment of the Environmental Exposure of Honeybees to Particulate

Matter Containing Neonicotinoid Insecticides Coming from Corn Coated Seeds,” Environmental Science &

Technology, vol. 46, no. 5 (2012), pp. 2592–2599.

209

V. Girolami, M. Marzaro, L. Vivian, et al., “Fatal Powdering of Bees in Flight with Particulates of Neonicotinoids

Seed Coating and Humidity Implication,” Journal of Applied Entomology, v. 136, n. 1-2 (2012), pp. 17-26.

210

Health Canada, “Evaluation of Canadian Bee Mortalities that Coincided with Corn Planting in Spring 2012,” 2013.

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Bee Health: The Role of Pesticides

Research has shown that honey bee exposure to sublethal levels of pesticides, including

neonicotinoids, exhibit impaired brood development,211 impaired olfactory associative

behavior,212 and impaired homing ability.213 Exposure to sublethal levels of neonicotinoid has also

been associated with higher rates of Nosema infection,214 and also reduced immune functioning in

those bees infected,215 making bees more susceptible to viral infections.216 In another study,

responsiveness to sucrose and the bee’s “waggle dancing” abilities217 were adversely affected

when honey bees ingested imidacloprid.218 Another study alternatively fed honey bee hives corn

syrup treated with imidacloprid, while other hives were fed untreated corn syrup. After 6 months,

nearly all the treated hives collapsed, while the untreated control hives remained healthy.219

Another study showed that imidacloprid ingestion by larvae of the stingless bee (Melipona

quadrifasciata anthidioidides) resulted in decreased survival rates, negatively affected

development of a specific region of the bee brain, and impaired walking behavior of newly

emerged adult worker bees.220

A 2013 study found that exposure to a combination of an insecticide (imidacloprid) and a miticide

(coumaphos) impaired learning and memory formation, important behaviors involved in foraging,

in honey bees exposed under “field-realistic concentrations.”221 A similar study also showed

211

Judy Y. Wu, Carol M. Anelli, and Walter S. Sheppard, “Sub-Lethal Effects of Pesticide Residues in Brood Comb on

Worker Honey Bee (Apis mellifera) Development and Longevity,” PLoS ONE, v. 6, n. 2 (2011), p. e14720.

212

En-Cheng Yang, et al., “Impaired Olfactory Associative Behavior of Honeybee Workers Due to Contamination of

Imidacloprid in the Larval Stage,” PLoS ONE, v. 7. n. 11 (November 2012), p.e49472.

213

T. Matsumoto, “Reduction in Homing Flights in the Honey Bee Apis mellifera After a Sublethal Dose of

Neonicotinoid Insecticides,” Bulletin of Insectology, vol. 66, no. 1 (2013), pp. 1-9.

214

J. Y. Wu, M. D. Smart, C. M. Anelli, et al., “Honey Bees (Apis mellifera) Reared in Brood Combs Containing High

Levels of Pesticide Residues Exhibit Increased Susceptibility to Nosema (Microsporidia) Infection,” Journal of

Invertebrate Pathology, v. 109 (2012), pp. 326-329; and J. Pettis, D. vanEngelsdorp, J. Johnson, et al., “Pesticide

Exposure in Honey Bees Results in Increased Levels of the Gut Pathogen Nosema,” Naturwissenschaften, v. 99 (2012),

pp. 153-158.

215

C. Alaux, J.-L. Brunet, C. Dussaubat, et al., “Interactions Between Nosema Microspores and a Neonicotinoid

Weaken Honeybees (Apis mellifera),” Environmental Microbiology, v. 12 (2012), pp. 774-782; J. Y. Wu, M. D. Smart,

C. M. Anelli, et al., “Honey Bees (Apis mellifera) Reared in Brood Combs Containing High Levels of Pesticide

Residues Exhibit Increased Susceptibility to Nosema (Microsporidia) Infection,” Journal of Invertebrate Pathology, v.

109 (2012), pp. 326-329; J. Pettis, D. vanEngelsdorp, J. Johnson, et al., “Pesticide Exposure in Honey Bees Results in

Increased Levels of the Hut Pathogen Nosema,” Naturwissenschaften, v. 99 (2012), pp. 153-158; and J. Pettis, E.

Lichtenberg, M. Andree, et al., “Crop Pollination Exposes Honey Bees to Pesticides Which Alters their Susceptibility

to the Gut Pathogen Nosema ceranae, PLoS ONE, v. 8. n. 7 (2013), p. e70182.

216

G. Di Priscoa, V. Cavaliereb, D. Annosciac, et al., “Neonicotinoid Clothianidin Adversely Affects Insect Immunity

and Promotes Replication of a Viral Pathogen in Honey Bees,” Proceedings of the National Academy of Sciences, v.

110, no. 46 (2013), pp. 18466–18471. See also F. Sánchez-Bayo, “The Trouble with Neonicotinoids,” Science, v. 346,

issue 6211, November 14, 2014.

217

Waggle dancing refers to when a bee communicates food locations to nest mates.

218

D. M. Eiri and J. C. Nieh, “A Nicotinic Cacetylcholine Receptor Agonist Affects Honey Bee Sucrose

Responsiveness and Decreases Waggle Dancing,” Journal of Experimental Biology, v. 215, n. 12 (2012), pp. 20222029.

219

Chensheng Lu, K. M. Warchol, and R. A. Callahan, “In Situ Replication of Honey Bee Colony Collapse Disorder,”

Bulletin of Insectology, v. 65, n. 1 (2012), pp. 99-106.

220

H. V. V. Tomé, G. F. Martins, M. August, et al., “Imidacloprid-Induced Impairment of Mushroom Bodies and

Behavior of the Native Stingless Bee Melipona quadrifasciata anthidioides,” PLoS ONE, v. 7, n. 6 (2012), p. e38406.

The mushroom body refers to a specific region of the bee brain.

221

S. M. Williamson and G. A. Wright, “Exposure to Multiple Cholinergic Pesticides Impairs Olfactory Learning and

Memory in Honeybees,” Journal of Experimental Biology, v. 216, n. 10 (February 2013), pp. 1799-1807.

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Bee Health: The Role of Pesticides

cognitive impairments from exposure to these same pesticides.222 Studies also have found

increased honey bee susceptibility to and mortality from Nosema223 after exposure to sublethal

concentrations of some pesticides (fipronil, amitraz, fluvalinate, chlorothalonil, pyraclostrobin,

and imidacloprid).224 Another study concluded that high levels of the fungicide chlorothalonil in

pollen and wax may be associated with entombing behavior,225 a sign that a hive has been

poisoned. These and other pesticides commonly used to control mites have also been shown to

have toxic effects on developing honey bee larvae at levels currently found in hives.226

A 2014 study reported linkages between CCD and sublethal exposure of neonicotinoid

pesticides—imidacloprid and clothianidin—which affected the winterization of the bees,

comparing exposed bee colonies to a control of non-exposed bee colonies.227 In the study, onehalf the bee colonies exposed to neonicotinoids exhibited symptoms resembling CCD and had

abandoned their hives during the winter, whereas one-sixth of the control colonies were lost

exhibiting Nosema ceranae symptoms. The control colonies did not abandon their hives but repopulated quickly; the surviving exposed colonies were small and either without queen bees or

had no brood, according to the study. Some have criticized this study for its small sample size,

lack of replication at each location, and the use of pesticide doses that may not reflect realistic

field conditions.228

Researchers at USDA and affiliated bee laboratories at land grant universities throughout the

United States continue to study the effects of neonicotinoids and other pesticides, including the

effects of interactions between pesticides and other stressors.229 Some of these studies

demonstrate that exposure by bees to certain pesticides and/or combinations of insecticides (e.g.,

neonicotinoids with miticides) may affect the bee’s overall energy budget, including its

metabolism, physical activity, digestion, and immunity; cause other types of physiological effects;

222

M. J. Palmer, et al., “Cholinergic Pesticides Cause Mushroom Body Neuronal Inactivation in Honeybees,” Nature

Communications, v. 4, n. 1634 (March 2013).

223

Nosema disease is a common bee disease, caused by a microscopic fungus (formerly considered to be a protozoan).

224

J. Aufauvre, D. G. Biron, C. Vidau, et al., “Parasite-Insecticide Interactions: A Case Study of Nosema ceranae and

Fipronil Synergy on Honeybee,” Scientific Reports vol. 2 (2012), no. 326; C. Vidau, M, Diogon, J. Aufauvre, et al.,

“Exposure to Sublethal Doses of Fipronil and Thiacloprid Highly Increases Mortality of Honeybees Previously Infected

by Nosem ceranae,” PLoS ONE, v. 6, n. 6 (2011), p. e21550; and C. Alaux, J. Brunet, C. Dussaubat, et al.,

“Interactions Between Nosema Microspores and a Neonicotinoid Weaken Honeybees (Apis mellifera),” Environmental

Microbiology, v. 12, n. 3 (2012), pp. 774-782; and J. Pettis, E. Lichtenberg, M. Andree, et al., “Crop Pollination

Exposes Honey Bees to Pesticides Which Alters Their Susceptibility to the Gut Pathogen Nosema ceranae, PLoS ONE,

v. 8. n. 7 (2013), p. e70182.

225

Entombing refers to when bees seal up hive cells containing pollen to remove them from use and protect the hive

from their contents. D. vanEngelsdorp, J. D. Evans, L. Donovall, et al., ‘‘‘Entombed Pollen’: A New Condition in

Honey Bee Colonies Associated with Increased Risk of Colony Mortality,” Journal of Invertebrate Pathology, v. 101

(2009), pp. 147–149.

226

W. Zhu, et al., “Four Common Pesticides, Their Mixtures and a Formulation Solvent in the Hive Environment Have

High Oral Toxicity to Honey Bee Larvae,” PLoS ONE, v. 9, n. 1, p. e77547.

227

Chensheng Lu, K. M. Warchol, and R. A. Callahan, “Sub-Lethal Exposure to Neonicotinoids Impaired Honey Bees

Winterization Before Proceeding to Colony Collapse Disorder,” Bulletin of Insectology, v. 67, n. 1 (2014), pp. 125-130.

228

Comments attributable to Jeff Pettis (USDA) and other university researchers, and also representatives of the agrochemical industries. See, for example, A. Boyle, “Hope for the Honeybees?” NBC News.com, May 14, 2014; and T.

Philpott, “Did Scientists Just Solve the Bee Collapse Mystery?” Mother Jones, May 20, 2014.

229

For example, presentations of preliminary findings of ongoing studies by Stephen Cook (USDA ARS Beltsville Bee

Lab) to DC Beekeepers Alliance, September 17, 2014; and presentations of unpublished work by Nathalie Steinhauer

(University of Maryland) to the Virginia Native Plant Society, October 9, 2014.

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Bee Health: The Role of Pesticides

and affect different parts of the bee’s nervous system, depending on the type or combination of

insecticides studied among other variables, including diet and nutrition.230

A few studies have examined the effects of pesticides on various species of bumble bees. One

study found that bumble bee exposure to imidacloprid may affect bee brain functioning, as well

as colony growth and nest conditions.231 Another study found that bumble bee colonies exposed

in a laboratory to low levels of imidacloprid had a significantly reduced growth rate and an 85%

reduction in queen production relative to untreated colonies.232 Other studies have found th

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