Cyanobacteria – interesting facts (2015)

Water 101

Cyanobacteria – interesting facts

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Prehistoric: Oldest life form (3½ billion yrs)/reported since 12th century

7,500 species: 1 of largest most important groups of bacteria

Photosynthetic – created earth’s O2 atmosphere

Naturally occurring in water (suspended)

Can be blue-green, pink, red, brown

– Red sea named for Oscillatoria blooms

– White flamingos turn pink eating Spirulina

• Some species can fix nitrogen

• All need a source of phosphorous

– Can store P for use when levels limited

– Slight Δ in water pH can > solubility of P and

other nutrients – gives cyanos upper hand

• Regulate buoyancy - optimal light/nutrients

Major genus of cyanobacteria in Oregon

Diverse group of aquatic, photosynthetic bacteria (not algae!)

Microcystis: Very hardy

Produces micocystin and anatoxin-a

Dolichospermum: Not as hardy

Produces Microcystin, anatoxin-a + 2 others

Aphanizomenon flos aquae:

Non-toxin producer in Oregon

Gleotrichia: Not as hardy

Produces microcystin

Water monitoring

Recreational

• Non regulatory

• Recommended when heavily used or

for source water

• Few lakes monitored

• River systems not usually monitored

• Monitoring strategies in flux

– Resource limitations pushing less testing

– Opting for other ways to reduce exposures/liability

o More education/outreach

o More signage at monitored & unmonitored lakes

Cyanobacterial blooms in Oregon

Willow Creek

Odell Lake from space

Willow Creek

2009-2015: Cell count data

70

4 toxins

Number of times identified

60

50

40

2 toxins

30

No toxins-Yet

20

2 toxins

10

0

Aphanizomenon

Dolichospermum

Gloeotrichia

Microcystis

Number of times genera of cyanobacteria identified over cell count guideline

values (GV) during advisories in monitored waterbodies.

2009-2015: Toxin data

2009-2015: Toxin data

20

Dog threshold

Number of times identified

Human threshold

16

12

8

Anatoxin: Rapidly degrades in sun/toxins

prevalent within first 2 weeks of cell growth,

Then drastically reduce

Microcystin

Extremely stable & persistent/resist common

chemical breakdown-prevalent worldwide

Cylindrospermopsin

Produces toxin continuously, unlike native

cyanobacteria that produce sporadically

4

0

Anatoxin

Cylindrospermopsin

Microcystin

Number of times cyanotoxins identified over recreational GVs during advisories in

monitored waterbodies - GVs dependent upon genera

Toxins, target organs & symptoms

Genetic and environmental factors can cause toxin production – research is ongoing

Toxins Produced

Type of

Toxin

Anatoxin-a

Target Organ

Nervous System

(20 ppb/ dogs 0.4 ppb)

Neurotoxins

Saxotoxin

Labored breathing, convulsions,

numbness, paralysis and death

Dog deaths caused by Anatoxin-a

Genus of Algae

Dolichospermum

Planktothrix

Oscillatoria

(10 ppb/dogs 0.02 ppb)

Liver

Microcystin

(10 ppb/dogs 0.2 ppb)

Hepatotoxin

Cylindrospermopsin

(20 ppb/dogs 0.4 ppb)

GI symptoms (food poisoning),

elevated liver enzymes in blood,

destruction of cells/blood vessels

Liver and Kidneys

Hepatotoxin

Symptoms like food

poisoning/Pos. kidney failure

Dolichospermum

Microcystis

Gloeotrichia

Cylindrospermopsis

Dolichospermum

Planktothrix

Oscillatoria

All species produce Lipopolysaccharides that can cause skin irritation

Things I need to know

• Ingestion is major route of exposure

• Current research says toxins are not absorbed through skin

- Contact w/cells can cause sensitivity: > exposure = more prone to rash

- Direct ‘contact’ can cause itchy eyes, sore throat and congestion

• No known antidotes

– Cannot remove by boiling filtering or treating with camping style filters

• Wash skin & clothes thoroughly with clean water (soap if available)

• Prevent pets from licking fur and rinse with clean water

– Symptoms develop within 1 hr. of exposure - seek veterinary help

• Children, people w/health conditions & pets at greatest risk

– Symptoms develop within 24 hrs. – If they persist seek medical help

Much remains unknown, but…

Recent studies have shown:

• Small % of toxins ingested w/food in blood/organs in RT

• Barriers to Microcystin (MC) uptake at various levels

1

– Can bioaccumulate in invertabrates but reduced up food web

– if taken up, aquatic organisms can detoxify & fish can rapidly excrete

– Biodilution occurs in food web: toxins degraded/excreted at every level2

• MC: liver/viscera/intestine/dig. gland/liquid fat/kidneys/gonads

• Fillets/meat: slight to no accumulation of MC or other toxins

– People can safely consume two 8-oz fillets/wk from water bodies (WB)

with blooms producing MC3

– Clean and discard everything but muscle tissue

1 Rohrlack et al. 2005; Tencalla and Dietrich 1997, 2 Ibelings and Havens, 2008, 3 F. Joan Hardy et. al., 2015, Poste et. al, 2012

Much remains unknown, but…

• Daphnia spp. vary in sensitivity to blooms

– all suffer reduced fitness in response to microcystis blooms

• MCs stress juvenile crayfish & freshwater mussels

• Some extracts can disrupt fish endocrine4

• Anatoxin-a can cause motor impairment in rainbow trout5

• MC can impair plant physiology & metabolism

• Cylindrospermopsin can inhibit plant pollen germination

• No chronic studies have been performed

• MC concen. > in WBs where MC concen. in water high

• MC highest in carnivorous fish

4 Marie, et al. 2012, 5 Oswald et al., 2013

Cyanobacteria outcompete for survival

• Long evolution produced diverse/highly effective adaptations to

ensure survival

• Can grow in depleted dissolved O2 environments detrimental

or fatal to fish

• Thrive anywhere & well adapted to environmental stress

– Live in hot springs, under ice packs & rocks in deserts, > pH conditions

– First organisms to colonize bare rock/soil after long periods of drought

– Photosynthesis increases pH – gives cyanos an edge – kills fish

– Exposure to UV, high solar radiation and extreme temps not a problem

– Deal with scarce or abundant resources

– When everything else is gone, they will survive

• Highly toxic strains outcompete toxic/non-toxic strains

• Competitive advantage increases likelihood of HAB events

Cyanobacteria outcompete for survival

Factors promoting survivability/dominance of cyanos1

Increased water & air temperature

 Water warms & mixing stops: restricts O2/nutrients to surface

 Cyanos move through water column for best food/conditions-others can’t

 Increased water temp - good for cyanos, bad for fish

Decreased water flows - increased salinity

 Cyanos quite salt tolerant

 Creates favorable conditions for invasion of marine HABs

Increases in CO2

 Cyanos pull N & CO2 from air/H2O: > access = > bloom growth and

occurrence

 Competition & shading kills other biota

Extreme weather events

 Increased transport of nutrients from land to water via runoff

 Drought increases length of time water can retain nutrients

 > nutrients & longer retention time = > food longer = > & denser blooms

1 Office of Water EPA 820-S-13-001 MC 4304T Fact Sheet, May 2013

Health advisory notification and outreach

• E-mail alerts/Gov-Delivery messages sent

DMAs/local HDs/DEQ/stakeholders/public

• News release issued

Posted on PHD/OHA websites

• Social media tools (e.g.- Twitter)

• Toll-free information line updated

877-290-6767

• Program website/map updated

http://www.healthoregon.org/hab

• Advisory signs posted

• Calls from public and

media addressed

Additional information

• www.healthoregon.org/hab

• Rebecca Hillwig – rebecca.hillwig@state.or.us

• David Farrer – david.g.farrer@state.or.us