Harmful Algal BloomsMary P. Skopec, Ph.D.
Executive Director
Iowa Lakeside Laboratory Regents Resource Center
Cyanobacteria a.k.a. “Blue-Green” AlgaeA quick primer…
• 1 Billion years and going strong• Photosynthetic bacteria
• Can produce green, blue, red, or brown pigments
• Found in fresh and salt water• Many can fix nitrogen (not all)• Resting spores• Mobile – regulate buoyancy• Can harvest nutrients from
sediments• Toxins with >100 variants
Black Hawk Lake, August 2014
How Toxic are Cyanotoxins?
Ricin
Soman
Sarin
Tabun
Rattlesnake Venom
After Chorus and Bartram, 1999; various references
Acute Toxicity Cytotoxic Dermatoxic Hepatotoxic Neurotoxic
Chronic Toxicity Carcinogen Tumor promotor Mutagen Teratogen Embryolethality Neurodegenerative disease
Slide Courtesy of Keith Loftin, USGS
• Human and Animal Health Risks• Hypoxia and Fish Kills• Water Treatment Costs• Lake Aesthetics –Clarity & Smell• Quality of Life
– Recreational Opportunities– Property Values– Tax Revenues– Employment
Impacts of Cyanotoxins and Harmful Algal Blooms
Graham and others, 2016, USGS OFR 2016-1174http://dx.doi.org/10.3133/ofr20161174
Harmful Algal Blooms are a Nationwide Issue
Cyanotoxins Are Detected in All Types of Waterbodies Throughout the Nation
Graham and others, 2016, USGS OFR 2016-1174http://dx.doi.org/10.3133/ofr20161174
In 1944, an Anabaena bloom in a lake in the Okoboji chain of lakes in Iowa was blown onshore and caused fatal poisoning of pigs and at least one dog that drank from the lake1
Backer et al, Toxins 2013, 5, 1597-1628; doi:10.3390/toxins5091597 1. “Pigs Die after Drinking Water from OKOBOJI”. Vindicator and Republican. Oct 19, 1944.
History of Toxic Algae in Iowa
“Storm Lake in Iowa experienced dramatic bloom events in 1952:
Associated with Anabaena flos–aquae blooms were estimated deaths of 5–7,000 gulls, 560 ducks, 400 coots, 200 pheasants, 50 squirrels, 18 muskrats, 15 dogs, 4 cats, 2 hogs, 2 hawks, 1 skunk, 1 mink, plus “numerous” songbirds.”
Rose E.T. Toxic algae in Iowa lakes. Proc. Iowa Acad. Sci. 1953;60:738–745.
2. “Lake Water not Only Made Dog Sick—It Killed Animal!” LeMars Globe Post. Dec 11, 1952.
3. Firkins, G.S. Toxic algae poisoning. Iowa State Coll. Vet. 1953, 15, 151–153.
Source: Iowa Cattleman
Carter Lake, IA – June 2004
History of IA Bloom MonitoringBig Creek State Park, June 2005
Sampling Protocol (2005-2016)Sampling Design
o Focus on beacheso Weekly sampleso Total microcystino Composite and Discrete (scum) samples
o Designed as survey with rapid turnaroundo Allows for public health decisions to be
madeo 20 µg/L total microcystin threshold level
establishedo Samples collected Monday/Tuesday
o Results usually available Thursday afternoon
Stage 1 – No algal toxin-related advisories
Sample result >2000 ug/L total microcystins?
Sample result >20 ug/L total microcystins?
Stage 2 – Post Warning sign; IDPH notified
Sample result >20 ug/L total microcystins?
Stage 3 – Beach closed; press release issued.
Sample result >2000 ug/L total microcystins?
No
No
No
Yes
Yes
Yes
Yes Sample collection and analysis
Sample collection and analysis Three-tiered advisory policy:Based on results from both composite and discrete samples• Stage 1 (no algal toxin-
related advisories)• Stage 2 (advisory) -
sample result exceeds 20 µg/L total microcystins
• Stage 3 (closure) – toxin result > 2000 µg/L; reported health case(s).
Iowa Advisory Policy (2016)
o General information signso Park staff notified
o post advisory signso Iowa Department of Public Health HANo IDNR Beach Monitoring websiteo Beach Monitoring Hotlineo Press releases
Public Notification
0
5
10
15
20
25
30
35
40
2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016
# of
Adv
isor
ies
Advisory Summary in Iowa(2006-2016)
Number of Lakes with Advisories(2006-2016)
02468
1012141618
# of
Lak
es
Microcystin Cylindrospermopsin4 ug/L 8 ug/L
1. a) Swimming Advisory: not to be exceeded on any day b) Recreational Criteria for Waterbody Impairment: not exceeded more than 10 percent of days per recreational season up to one calendar year.
2. Based on Children’s Recreation Exposure
3. Non-cancer endpoints
4. https://www.epa.gov/sites/production/files/2016-12/documents/draft-hh-rec-ambient-water-swimming-document.pdf
December 2016, EPA published Draft Recreational Criteria for Algal Toxins
0
50
100
150
200
250
300
350
400
2013 2014 2015 2016 Total
# of
Asv
isor
ies
> 20 ug/L>4 ug/L
Impact of Changing Microcystin Advisory Threshold
Multiple Toxins Co-Occur in Cyanobacterial Blooms
Graham and others, 2010, ES&T
Little information regarding the effects of ingesting multiple toxin compounds
oThe Iowa Department of Public Health (IDPH) is responsible for tracking illness in humans attributed to microcystin poisoning
Illness Surveillance
oThe Iowa Department of Public Health (IDPH) is responsible for tracking illness in humans attributed to microcystin poisoning
oReporting of suspected cases of microcystinpoisoning required of health care providers
Illness Surveillance
oThe Iowa Department of Public Health (IDPH) is responsible for tracking illness in humans attributed to microcystin poisoning
oReporting of suspected cases of microcystinpoisoning required of health care providers
oThe IDPH works cooperatively with local health care partners in this tracking processoLocal county environmental healthoLocal network of health care providers
Illness Surveillance
10
2 2
4
8
2
2011 2012 2013 2014 2015 2016
Num
ber
of C
ases
Number of Suspected Cases of Microcystin Poisoning Reported to IDPH
Four of the ten cases in 2011 were at a triathlon
Complaint Type(2011-2016)
0
1
2
3
4
5
6
7
8
9
Solutions?
Slide: Hans Paerl; UNC; https://www.epa.gov/sites/production/files/2014-05/documents/paerl_epa_webinar_presentation_5_2014.pdf
An increasing number of studies finding that BOTH nitrogen and phosphorus reductions are needed
1. Xu, H., H. W. Paerl, B. Q. Qin, G. W. Zhu, and G. Gao. 2010. Nitrogen and phosphorus inputs control phytoplankton growth in eutrophic Lake Taihu, China. Limnology and Oceanography 55:420–432.
2. Xu, H., Paerl, H.W., Zhu, G. et al. Hydrobiologia (2017) 787: 229. doi:10.1007/s10750-016-2967-4. Long-term nutrient trends and harmful cyanobacterial bloom potential in hypertrophic Lake Taihu, China.
3. Conley, D. J., H. W. Paerl, R. W. Howarth, D. F. Boesch, S. P. Seitzinger, K. E. Havens, C. Lancelot & G. E. Likens, 2009. Controlling eutrophication: nitrogen and phosphorus. Science 323: 1014–1015.
4. Paerl, H. W., N. S. Hall, and E. S. Calandrino. 2011a. Controlling harmful cyanobacterial blooms in a world experiencing anthropogenic and climaticinduced change. Science of the Total Environment 409:1739–1745.
5. Paerl, H. W., H. Xu, M. J. McCarthy, G. W. Zhu, B. Q. Qin, Y. P. Li, and W. S. Gardner. 2011b. Controlling harmful cyanobacterial blooms in a hyper-eutrophic lake (Lake Taihu, China): The need for a dual nutrient (N & P) management strategy. Water Research 45:1973–1983.
6. Beaulieu Marieke , Pick Frances , Gregory-Eaves Irene , (2013), Nutrients and water temperature are significant predictors of cyanobacterial biomass in a 1147 lakes data set, Limnology and Oceanography, 58, doi: 10.4319/lo.2013.58.5.1736.
“Bioavailability of both N and P during the summer plays a key role in sustaining cyanobacterial blooms.”2
National Lake Assessment (1,2)• Total Nitrogen 1100 ug/L• Total Phosphorus 87 ug/L
Region 7 (3) Lake Benchmarks• Total Nitrogen 700 ug/L• Total Phosphorus 35 ug/L
1. Yuan, L. L. and Pollard, A. I. (2015), Deriving nutrient targets to prevent excessive cyanobacterial densities in U.S. lakes and reservoirs. Freshw Biol, 60: 1901–1916.
2. Yuan, L. L., Pollard, A. I., Pather, S., Oliver, J. L. and D'Anglada, L. (2014), Managing microcystin: identifying national-scale thresholds for total nitrogen and chlorophyll a. Freshw Biol, 59: 1970–1981. doi:10.1111/fwb.12400
3. http://cpcb.ku.edu/media/cpcb/progwg/html/assets/nutrientwg/Lake_RTAG_2011Jun.pdf
Nutrient Goals
Iowa DNR Lake Monitoring Program (138 lakes)• Median Nitrate 1900 ug/L• Median Total Phosphorus 78.3 ug/L
Nutrient Goals: Comparison to Iowa Lakes
Recommendations
1. Monitoring outside of “classic” recreation season and locations (non-beach areas)
1. Pilot monitoring in Okoboji area 2017.2. Add monitoring at County and City beaches3. Expanded testing for other cyanotoxins
(cylindrospermopsin, saxitoxin, anatoxin)4. Increase Public Outreach for Reporting of Illness
Stuart Schmitz, M.S., P.E. State Toxicologist
Iowa Department of Public Health [email protected] (515) 281-8707
Health InformationAcknowledgements
Mary P. Skopec, Ph.D.Executive Director
Iowa Lakeside Laboratory: Regents Resource CenterUniversity of Iowa
Questions?
Rock Creek Lake August 18, 2006