Migratory Bird Hunting; Temporary Approval of Tungsten-Polymer Shot as Nontoxic for the 1998-99 Season

DEPARTMENT OF INTERIOR

Fish and Wildlife Service

50 CFR Part 20

RIN 1018-AE66

Migratory Bird Hunting; Temporary Approval of Tungsten-Polymer

Shot as Nontoxic for the 1998-99 Season

AGENCY: Fish and Wildlife Service, Interior.

ACTION: Proposed rule.

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SUMMARY: The U.S. Fish and Wildlife Service (Service) proposes to amend

Section 20.21(j) and provide temporary approval of tungsten-polymer

shot as nontoxic for the 1998-99 migratory bird hunting season, except

in the Yukon-Kuskokwim (Y-K) Delta, Alaska. A toxicological report

includes an extensive literature review, and analysis of tungsten and

Nylon 6 (the polymer) suggests that these compounds are nontoxic under

assumed use and in the environment. The toxicity study reveals no

adverse effects over a 30-day period on mallards (Anas platyrhynchus)

dosed with 8 BB-size tungsten-polymer shot. However, there is some

concern that the absorption of tungsten into the femur, kidney, and

liver could potentially affect the spectacled eider (Somateria

fischeri), a species already subject to adverse weather, predation, and

lead poisoning on the Yukon-Kuskokwim (Y-K) Delta, Alaska. Until a

reproductive/chronic toxicity test has been completed and the Service

has reviewed the results, the Service proposes not to approve the use

of tungsten-polymer shot on the Y-K Delta.

DATES: Comments on the proposed rule must be received no later than

August 26, 1998.

ADDRESSES: Comments may be sent to the Chief, Office of Migratory Bird

Management (MBMO), U.S. Fish and Wildlife Service, 1849 C Street, NW.,

ms 634-ARLSQ, Washington, DC 20240. The public may inspect comments

during normal business hours in room 634, Arlington Square Building,

4401 N. Fairfax Drive, Arlington, Virginia.

FOR FURTHER INFORMATION CONTACT: Paul R. Schmidt, Chief, Office of

Migratory Bird Management, (703) 358-1714.

SUPPLEMENTARY INFORMATION: Since the mid-1970s, the Service has sought

to identify shot that does not pose a significant toxic hazard to

migratory birds or other wildlife. Currently, only steel and bismuth-

tin shot are approved by the Service as nontoxic. The Service

previously granted temporary approval

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for bismuth-tin on two separate actions for the hunting seasons of

1994-95 and 1995-96. Tungsten-iron shot was given temporary approval

for the 1997-98 migratory bird hunting season. The Service believes

that approval of other suitable candidate shot materials as nontoxic is

feasible. Compliance with the use of nontoxic shot has increased over

the last few years. The Service believes that compliance will continue

to increase with the approval and availability of other nontoxic shot

types.

Federal Cartridge Company's (Anoka, Minnesota) candidate shot is a

matrix of Nylon 6 or 11 polymer surrounding particles of elemental

tungsten. Shot made from this material has a density of approximately

11.2 g/cm3 or approximately the density of lead. The shot

will contain approximately 95.5 percent tungsten and 4.5 percent Nylon

6 or 11 by weight, plus sufficient iron to attract a magnet.

Federal's application includes a description of the new tungsten-

polymer (TP) shot, a toxicological report (Barr, 1996), and the results

of a 30-day dosing study of the toxicity of this shot in game-farm

mallards (Anas platyrhynchos). The toxicological report incorporates

toxicity information (a synopsis of acute and chronic toxicity data for

mammals and birds, potential for environmental concern, and toxicity to

aquatic and terrestrial invertebrates, amphibians and reptiles) and

information on environmental fate and transport (shot alteration,

environmental half-life, and environmental concentration). The toxicity

study is a 30-day dosing test to determine if the candidate shot poses

any deleterious effects to game-farm mallards. This will meet the

requirements for Tier 2 consideration, as described in 50 CFR

20.134(b)(3).

Toxicity Information

There is considerable difference in the toxicity of soluble and

insoluble compounds of tungsten. Elemental tungsten is virtually

insoluble and is, therefore, expected to be relatively nontoxic. The

potential toxicity of nylon compounds due to degradation is primarily

associated with the stabilizers, antioxidants, plasticizers, and

unreacted prepolymers. Residual caprolactum has been found in some

commercial Nylon 6 products, but little concern regarding this compound

has been developed (Patty, 1981). Even though most toxicity tests

reviewed were based on soluble tungsten compounds rather than elemental

tungsten (while the toxicity of Nylon 6 is negligible due to its

insolubility), there appears to be no basis for concern of toxicity to

wildlife for the TP shot (metallic tungsten and Nylon 6) via ingestion

by fish, birds, or mammals (Bursian et al., 1996; Gigiena, 1983; Patty,

1981; Industrial Medicine, 1946; Karantassis, 1924).

Environmental Fate and Transport

Tungsten is insoluble in water and, therefore, not mobile in

hypergenic environments. Tungsten is very stable in acids and does not

easily complex. Preferential uptake by plants in acid soil suggests

that uptake of tungsten in the anionic form is associated with tungsten

minerals rather than elemental tungsten (Kabata-Pendias and Pendias,

1984).

Environmental Concentrations

Calculation of the estimated environmental concentration (EEC) of

tungsten in a terrestrial ecosystem is based on 69,000 shot per hectare

(Pain, 1990), assuming complete erosion of material in 5 cm of soil.

The EECs for tungsten and Nylon 6 in soil are 58.3 mg/kg and 2.7 mg/kg,

respectively. Calculation of the EEC in an aquatic ecosystem assumes

complete erosion of the shot in one cubic foot of water. The EECs in

water for tungsten and Nylon 6 are 18.7 mg/L and 0.9 mg/L,

respectively. The Hazard Quotients assume that complete erosion of the

shot components would occur; however, the TP shot is considered

insoluble and is stable in basic, neutral, and mildly acidic

environments. Therefore, erosion is expected to be minimal, and adverse

effects on biota are not expected to occur.

Effects on Birds

An extensive literature review provided information on the toxicity

of elemental tungsten to waterfowl and other birds. Ringelman et al.

(1993) orally dosed 20 8-week-old game-farm mallards with 12-17 (1.03g)

tungsten-bismuth-tin (TBT) pellets and monitored them for 32 days for

evidence of intoxication. No birds died during the trial, gross lesions

were not observed during the postmortem examination, histopathological

examinations did not reveal any evidence of toxicity or tissue damage,

and tungsten was not detectable in kidney or liver samples. The authors

concluded that TBT shot presented virtually no potential for acute

intoxication in mallards.

Kraabel et al. (1996) assessed the effects of embedded TBT shot on

mallards and concluded that TBT was not acutely toxic when implanted in

muscle tissue. Inflammatory reactions to TBT shot were localized and

had no detectable systemic effects on mallard health.

Nell (1981) fed laying hens (Gallus domesticus) 0.4 or 1 g/kg

tungsten in a commercial mash for five months to assess reproductive

performance. Weekly egg production was normal and hatchability of

fertile eggs was not affected. Exposure of chickens to large doses of

tungsten either through injection or by feeding, resulted in an

increased tissue concentration of tungsten and a decreased

concentration of molybdenum (Nell, 1981). The loss of tungsten from the

liver occurred in an exponential manner with a half-life of 27 hours.

The alterations in molybdenum metabolism seemed to be associated with

tungsten intake rather than molybdenum deficiency. Death due to

tungsten occurred when tissue concentrations increased to 25 mg/g

liver. At that concentration, xanthine dehydrogenase activity was zero.

Nylon 6 is the commercially important homopolymer of caprolactum.

Most completely polymerized nylon materials are physiologically inert,

regardless of the toxicity of the monomer from which they are made

(Peterson, 1977). Few data exist on the toxicity of Nylon 6 in animals.

Most toxicity studies relate to thermal degradation products and so are

not relevant to the exposure of wildlife to shot containing nylon.

Montgomery (1982) reported that feeding Nylon 6 to rats at a level of

25 percent of the diet for 2 weeks caused a slower rate of weight gain,

presumably due to a decrease in food consumption and feed efficiency.

However, the rats suffered no anatomic injuries due to the consumption

of nylon.

Federal's 30-day dosing study (Bursian et al., 1996) included four

treatment groups of game-farm mallards (16 birds in each group, 8 males

and 8 females) exposed to different types of shot: 8 No. 4 steel, 8 No.

4 lead, 8 BBs of tungsten-polymer, and none (control). All TP-dosed

birds survived the test with no significant alteration in body weight.

There were no changes in hematocrit, hemoglobin concentration, or ALAD

activity. The only significant difference between no-shot, steel, and

TP males in any of the 25 plasma chemistry parameters at day 15 was an

increase in the albumin/globulin ratio in the TP birds when compared to

the other two groups, but the authors felt this was not remarkable.

Three TP-dosed males developed mild biliary stasis. The authors

attributed this to the intubating of mallards with 8 BBs of TP shot

inducing a pathological condition, however, slight, that is not found

in the control birds. No other histopathological lesions were found. In

general, no adverse effects were seen in mallards

[[Page 40076]]

given 8 BB-size TP shot and monitored over a 30-day period. Tungsten

was detected in the femur of 2 TP-dosed females and the kidneys of 2

TP-dosed birds; in both tissues, concentrations were only slightly

above detection limits.

Based on the results of the toxicological report and the toxicity

test (Tier 1 and 2), the Service concludes that TP shot (95.5 percent

tungsten and 4.5 percent Nylon 6 or 11, by weight with <1 percent

residual lead), does not pose a significant danger to migratory birds

or other wildlife and their habitats. However, the Service has some

concern that the absorption of tungsten into the femur, kidney, and

liver could potentially affect the spectacled eider (Somateria

fischeri), a species already subject to adverse weather, predation, and

lead poisoning on the Yukon-Kuskokwim (Y-K) Delta, Alaska. Until a

reproductive/chronic toxicity test has been completed and the Service

has reviewed the results, TP shot cannot be approved for the Y-K Delta.

The first condition of approval is toxicity testing. Candidate

materials not approved under Tier 1 and/or 2 testing are subjected to

standards of Tier 3 testing. The scope of Tier 3 includes chronic

exposure under adverse environmental conditions and effects on

reproduction in game-farm mallards, as outlined in 50 CFR 20.134

(b)(4)(A and B) (Tier 3) and in consultation with the Service's Office

of Migratory Bird Management and the U.S. Geological Survey's Division

of Biological Resources. This study includes assessment of long-term

toxicity under depressed temperature conditions using a nutritionally-

deficient diet, as well as a moderately long-term study that includes

reproductive assessment. The tests require the applicant to demonstrate

that TP shot is nontoxic to waterfowl and their offspring.

The second condition of approval is testing for residual lead

levels. Any TP shot with lead levels equal to or exceeding 1 percent

will be considered toxic and, therefore, illegal. In the August 18,

1995, Federal Register (60 FR 43314), the Service indicated that it

would establish a maximum level for residual lead. The Service has

determined that the maximum environmentally acceptable level of lead in

any nontoxic shot is trace amounts of <1 percent, and has incorporated

this requirement (50 CFR 20.134(b)(5)) in the December 1, 1997, final

rule (62 FR 63608).

The third condition of approval involves enforcement. In the August

18, 1995, Federal Register (60 FR 43314), the Service indicated that

final unconditional approval of any nontoxic shot would be contingent

upon the development and availability of a noninvasive field testing

device. Several noninvasive field testing devices are under development

to separate TP shot from lead shot. Furthermore, TP shot can be drawn

to a magnet as a simple field detection method. This requirement was

incorporated into regulations at 50 CFR 20.134(b)(6) in the December 1,

1997, final rule (62 FR 63608).

This proposed rule would amend 50 CFR 20.21(j) by approving

temporary approval of TP shot as nontoxic for migratory bird hunting,

except in the Yukon-Kuskokwim (Y-K) Delta, Alaska. It is based on the

original request made to the Service by Federal Cartridge Company on

July 16, 1997, the toxicological report, and acute toxicity study.

Results of the toxicological report and 30-day toxicity test undertaken

for Federal Cartridge Company document the apparent absence of any

deleterious effects of TP shot when ingested by captive-reared mallards

or to the ecosystem.

References

Barr Engineering Company. 1996. Toxicology report on new shot.

Contract Report 2302118/40970091/CET. 21 pp.

Bursian, S. J., M. E. Kelly, R. J. Aulerich, D. C. Powell, and S.

Fitzgerald. 1996. Thirty-day dosing test to assess the toxicity of

tungsten-polymer shot in game-farm mallards. Report to Federal

Cartridge Co. 77 pp.

Gigiema I. Sanitariya. 1983. Mezhdunarodnaya Kniga. Moscow, USSR.

48(7):77.

Grandy, J. W., L. N. Locke and G. E. Bagley. 1968. Relative toxicity

of lead and five proposed substitute shot types to pen-reared

mallards. Journal of Wildlife Management 32(3):483-488.

Industrial Medicine. 1946. Volume 15, p. 482.

Interagency Ecosystem Management Task Force. 1995. The ecosystem

approach: healthy ecosystems and sustainable economics. Volume II-

Implementation Issues.

Kabata-Pendias, A. and H. Pendias. 1984. Trace elements in soil and

plants. CRC Press, Inc. Boca Raton, FL.

Karantassis, T. 1924. On the toxicity of compounds of tungsten and

molybdenum. Ann. Med. 28:1541091543.

Kraabel, F. W., M. W. Miller, D. M. Getzy, and J. K. Ringleman.

1996. Effects of embedded tungsten-bismuth-tin shot and steel shot

on mallards. Journal of Wildlife Diseases 38(1):1098.

Montgomery, R. R. 1982. Polymers. In Patty's Industrial Hygiene and

Toxicology, Vol. IIIA (G. D. Clayton and F. E. Clayton, Eds.) pp.

4209-4526. John Wiley and Sons, NY.

Nell, J. A, W. L. Bryden, G. S. Heard, and D. Balnave. 1981.

Reproductive performance of laying hens fed tungsten. Poultry

Science 60(1):257-258.

Pain, D. J. 1990. Lead shot ingestion by waterbirds in the

Carmarque, France: an investigation of levels and interspecific

difference. Environ. Pollut. 66:273-285.

Patty's Industrial Hygiene and Toxicology. 1981. Wiley Interscience.

Wiley & Sons, Inc. NY, NY. Third Edition.

Peterson, J. E. 1977. Industrial Health. Prentice-Hall, Englewood

Cliffs, NJ.

Ringelman, J. K., M. W. Miller and W. F. Andelt. 1993. Effects of

ingested tungsten-bismuth-tin shot on mallards. Colorado Division of

Wildlife, Fort Collins, 24 pp.

NEPA Consideration

In compliance with the requirements of section 102(2)(C) of the

National Environmental Policy Act of 1969 (42 U.S.C. 4332(C)), and the

Council on Environmental Quality's regulation for implementing NEPA (40

CFR 1500-1508), the Service prepared an Environmental Assessment (EA)

in May, 1998. This EA is available to the public at the location

indicated under the ADDRESSES caption. Based on review and evaluation

of the information in the EA, the Service has determined that amending

50 CFR 20.21(j) to provide approval of TP shot as nontoxic for

migratory bird hunting would not be a major Federal action that would

significantly affect the quality of the human environment.

Endangered Species Act Considerations

Section 7 of the Endangered Species Act (ESA) of 1972, as amended

(16 U.S.C. 1531 et seq.), provides that Federal agencies shall ``insure

that any action authorized, funded or carried out . . . is not likely

to jeopardize the continued existence of any endangered species or

threatened species or result in the destruction or adverse modification

of (critical) habitat . . .'' The Service has completed a Section 7

consultation under the ESA for this proposed rule, which stated the

``use of tungsten-polymer shot is not likely to adversely affect listed

species.'' The result of the Service's consultation under Section 7 of

the ESA is available to the public at the location indicated under the

ADDRESSES caption.

Regulatory Flexibility Act, Executive Order 12866, and the

Paperwork Reduction Act

The Regulatory Flexibility Act of 1980 (5 U.S.C. 601 et seq.)

requires the preparation of flexibility analyses for rules that will

have a significant effect on a substantial number of small entities,

which includes small businesses, organizations, or

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governmental jurisdictions. The economic impacts of annual hunting on

small business entities were analyzed in detail and a Small Entity

Flexibility Analysis (Analysis), under the Regulatory Flexibility Act

(5 U.S.C. 601 et seq.), was issued by the Service in 1996 (copies

available upon request from the Office of Migratory Bird Management).

The Analysis documented the significant beneficial economic effect on a

substantial number of small entities. The primary source of information

about hunter expenditures for migratory game bird hunting is the

National Hunting and Fishing Survey, which is conducted at 5-year

intervals. The Analysis utilized the 1991 National Hunting and Fishing

Survey and the U.S. Department of Commerce's County Business Patterns

from which it was estimated that migratory bird hunters would spend

between $254 and $592 million at small businesses in 1996. The approval

of tungsten-polymer as an alternative shot to steel and bismuth-tin

will have a minor positive impact on small businesses by allowing them

to sell a third nontoxic shot to the hunting public. However, the

overall effect to hunting expenditures in general would be minor.

Therefore, the Department of the Interior certifies that this document

will not have a significant economic effect on a substantial number of

small entities under the Regulatory Flexibility Act. The approved shot

will merely supplement nontoxic shot already in commerce and available

throughout the retail and wholesale distribution systems, therefore,

this rule would have minimal effect on such entities. The Service

anticipates no dislocation or other local effects with regard to

hunters and others. This document is not a significant rule subject to

Office of Management and Budget review under Executive Order 12866.

This rule does not contain collections of information that require

approval by the Office of Management and Budget under 44 U.S. C. 3501

et seq. The Service does have OMB approval (1018-0067; expires 06/30/

2000) for information collection relating to what manufacturers of shot

are required to provide the Service for the nontoxic shot approval

process. For further information see 50 CFR 20.134.

Unfunded Mandates Reform

The Service has determined and certifies pursuant to the Unfunded

Mandates Act, 2 U.S.C. 1502 et seq., that this rulemaking will not

impose a cost of $100 million or more in any given year on local or

State governments or private entities.

Civil Justice Reform--Executive Order 12988

The Department has determined that these proposed regulations meet

the applicable standards provided in Sections 3(a) and 3(b)(2) of

Executive Order 12988.

List of Subjects in 50 CFR Part 20

Exports, Hunting, Imports, Reporting and recordkeeping

requirements, Transportation, Wildlife.

Accordingly, the Service proposes to amend part 20, subchapter B,

chapter 1 of Title 50 of the Code of Federal Regulations as follows:

PART 20--[AMENDED]

1. The authority citation for part 20 continues to read as follows:

Authority: 16 U.S.C. 703-712 and 16 U.S.C. 742 a-j.

2. Section 20.21 is amended by revising paragraph (j) introductory

text and adding paragraph (j)(3) to read as follows:

20.21 Hunting methods.

* * * * *

(j) While possessing shot (either in shotshells or as loose shot

for muzzleloading) other than steel shot, or bismuth-tin (97 parts

bismuth: 3 parts tin with <1 percent residual lead) shot, or tungsten-

iron ([nominally] 40 parts tungsten: 60 parts iron with <1 percent

residual lead) shot, or tungsten-polymer (95.5 part tungsten: 4.5 parts

Nylon 6 or 11 with <1 percent residual lead) shot, or such shot

approved as nontoxic by the Director pursuant to procedures set forth

in 20.134, provided that:

* * * * *

(3) Tungsten-polymer shot (95.5 parts tungsten: 4.5 parts Nylon 6

or 11 with <1 percent residual lead) is legal as nontoxic shot for the

1998-99 migratory bird hunting season, except for the Yukon-Kuskokwim

Delta habitat in Alaska.

Dated: July 14, 1998.

Donald J. Barry,

Assistant Secretary for Fish and Wildlife and Parks.

[FR Doc. 98-19890 Filed 7-24-98; 8:45 am]

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