# Presentation: 559618

## Preliminary Assessment of Cyanotoxin Occurrence in Lakes and Reservoirs in the 

**United States**

- Keith A. Loftin, Jennifer L. Graham, Michael T. Meyer, Andrew C. Ziegler, Julie E. Dietze
- U.S. Geological Survey
- Susan Holdsworth, Ellen Tarquinio
- U.S. Environmental Protection Agency

## Acknowledgements

- USEPA
-    Office of Wetlands, Oceans and Watersheds
-       (National Lake Assessment Website:  http://www.epa.gov/owow/lakes/lakessurvey/)
- USGS
-    Toxic Substance Hydrology Program
-       (http://toxics.usgs.gov/regional/emc/)
- Disclaimer:
- Any use of trade, product, or firm names in this presentation is for descriptive
- purposes only and does not imply endorsement by the U.S. Government.

**Notes:**
Our research group.

## Outline

- Introduction to Cyanotoxins and Cyanobacteria
- 	USGS cyanotoxin sampling protocol:
- 	_[http://pubs.usgs.gov/sir/2008/5038](http://pubs.usgs.gov/sir/2008/5038)_
- C.	Previous Occurrence in Midwest 1999-2006
- D.	Toxin Studies
- 1.  2007 EPA National Lake Assessment (2007 US EPA NLA)
-         2. 2006 USGS Midwestern US Cyanotoxin Reconnaissance of
-             Cyanobacterial Blooms (2006 USGS MCR)
- E.	Take Home Message

**Lakeline, 26(2), Summer 2006.**

## Concerns and Guidelines

- Known Acute effects and chronic effects
- 		- hepatotoxins
- 		- neurotoxins
- 		- dermatotoxins
- 		- carcinogens
- EPA Contaminant Candidate List 3
- Anatoxin-a
- Cylindrospermopsin
- Microcystin-LR
- WHO guidelines – Microcystin-LR
- Drinking water – 1.0 ppb
- Recreational water
- Low Risk - < 10 ppb
- Moderate Risk - 10-20 ppb
- High Risk - > 20 ppb

- Binder Lake, IA August 2006

## At Least 35 U.S. States With Reports of Cyanotoxin Associated Poisonings

**At Least 35 U.S. States With Reports**** of Cyanotoxin Associated Poisonings**

**Cyanobacteria Made the News in at Least 21 U.S. States During 2006**

- East Okoboji Lake, IA June 2000

- After Graham, 2006

## Photic Zone Sampling vs. Bloom Sampling

**Upper Gar, IA August 2006**

- Cyanotoxin transport:
- 	Intracellular:
- 		Wind
- 		Hydraulic
- 		Bouyancy Regulation
- 	Extracellular:
- 		Hydraulic (Dissolved-Phase)
- 		Particulate-Bound
- Sampling protocol critical to ability to interpret data!
- Higher concentrations of cyanobacteria and toxins more
-  likely in wind blown accumulations near shore.

**Cheney Reservoir, KS, June 2003**

## Environmental Distribution of Cyanotoxins“The Quick Version”

- Total Toxin

- Total Toxin = Extracellular Toxin + Intracellular Toxin + Particulate Toxin

## Microcystins were Commonly Found in the Midwest by ELISA (1999 – 2006)

- After Graham and others 2004 and 2006

- Integrated photic zone
- 	samples.
- 78% (n = 359) of lakes had
- 	 at least  one detectable
- 	 occurrence of toxins.
- Total concentrations
- 	ranged from:
- 		      < 0.10 to 52 ppb.

**Mozingo Lake, MO October 2001**

**Notes:**
1999 – 2006 Jen’s historical work,  with SDI kit and then Abraxis

## Randomly selected lakes for 2007 EPA National Lake Assessment - Photic Zone Sampling

**Randomly selected lakes for 2007 EPA National Lake Assessment - ****Photic Zone Sampling**

- Image from EPA 841-F-06-002

- (_[http://www.epa.gov/owow/lakes/lakessurvey/](http://www.epa.gov/owow/lakes/lakessurvey/)__)_
- Total lakes: n=1150 for Microcystins

- Total microcystin
- 	samples collected in
- 	photic zone in deepest
- 	part of lake.
- All samples were
- 	analyzed by ELISA.
- 2 % of samples will
- 	be analyzed by
- 	LC/MS/MS for
- 	confirmation.

## 2007 EPA NLA – Photic Zone Sampling Microcystins Were Found Throughout the United States Especially in the Upper Midwest.

**2007 EPA NLA – Photic Zone Sampling ****Microcystins Were Found Throughout the United States Especially in the Upper Midwest.**

- % Overall Detections (with Reference Lakes and
- 	Resampled Lakes):   32 %  (401/1238)

## 2006 USGS Midwestern US Cyanotoxin Reconnaissance – Targeted Cyanobacterial Blooms and Accumulations

**2006 USGS Midwestern US Cyanotoxin Reconnaissance – Targeted Cyanobacterial Blooms and Accumulations**

- Cyanobacterial blooms and accumulations in 23 midwestern
- 	 lakes (KS, MO, IA, MN) were targeted over a 1 week period in
- 	August 2006.
- Measurements included:  water chemistry, cyanotoxin analysis by
-       ELISAs and LC/MS/MS (dissolved and **total**), taste-and-odor
-       compounds (SPME-GC/MS), chlorophyll a (fluorescence), and
-       phytoplankton ID.

## 2006 USGS Midwest US Cyanotoxin Reconnaissance

-   During August 2006 all lakes (n=23) had detectable microcystins when ELISA and LC/MS/MS are combined, 30% had detectable Anatoxin-a, and 9% had detectable Nodularin-R.

- ELISA (MRL = 0.10 ppb, 0.02 ppb, 0.04 ppb)

- 1.   ELISA detections of Cylindrospermopsin were not reproduced by LC/MS/MS
- 2.   ELISA detections for Saxitoxins could not be confirmed at this time.  Still
- 	  working to include these compounds in our LC/MS/MS method.

- LC/MS/MS (MRL = 0.010 ppb)

## 2006 USGS Midwest Recon Microcystins Were the Dominant Class of Cyanotoxins (ELISA - 23 lakes)

**Upper Pine Lake, IA August 2006**

**Rock Creek Lake, IA August 2006**

## 2006 USGS MCR – Blooms and AccumulationsMicrocystins –LR and –RR were the Most Abundant Congeners and Microcystin–RR had the Highest Concentrations.

- No detections  above 0.010 ppb for Cylindrospermopsin, Deoxycylindrospermopsin,
- and Lyngbyatoxin-A.

**Notes:**
Research 40 (13), pp. 2549-2560

## 2006 USGS MCR Cyanotoxin Mixtures Were Commonly Found in Midwest Lakes and Reservoirs in 2006 by LC/MS/MS with Up to 9 Toxins Measured in One Sample.

**Notes:**
Start on y axis with number of sample and then follow the bar to the x-axis for the number of toxins or vice versa.  Example, 22 samples had at least 1 toxin and 21 samples had at least 2 toxins.

## Comparison of ELISA Results for Microcystins

- Photic Zone Sampling vs. Blooms and Accumulations
- Higher Detection Frequencies and Higher Concentrations were Observed in Blooms and
-  Accumulations than in Photic Zone Sampling.

- Study objectives dictate sample collection procedures (i.e. photic zone vs blooms and accumulations, etc.).

## Take Home Message...

- Cyanotoxins are present at levels that may be of concern for human health and ecological impact in some cases.  Specifically, microcystins are found nationwide and are frequently encountered in the Midwest.
- Anatoxin-a occurred in  30% of the 2006 USGS Midwest Recon at levels up to 9.5 ppb.
- Predictably, higher detection frequencies and higher concentrations of toxins can be encountered in  cyanobacterial blooms and  accumulations versus photic
- 	zone sampling.
- In the 2007 EPA study (photic zone sampling),  9 (0.7 %) lakes exceeded WHO recreational guidelines (20 ppb) and 143 (12 %) lakes exceeded WHO drinking water guidelines (1.0 ppb) for microcystins.
- In the 2006 USGS Midwest Recon (Bloom and Accumulation sampling),  4 (17 %) lakes exceeded WHO recreational guidelines (20 ppb) and 18 (78 %) lakes exceeded WHO drinking water guidelines (1.0 ppb) for microcystins.  Microcystin-LR, one of the most toxic microcystin congeners, was detected most frequently   (91 %).
- LC/MS/MS results indicate that toxin mixtures may be fairly common.

## Jennifer Graham jlgraham@usgs.gov (785) 832-3511

_**Jennifer Graham**_** ****jlgraham@usgs.gov ****(785) 832-3511**

_**Keith Loftin**_**kloftin@usgs.gov****(785) 832-3543**

- _Additional Information Available on the Web:_
- Cyanobacteria - _[http://ks.water.usgs.gov/Kansas/studies/qw/cyanobacteria](http://ks.water.usgs.gov/Kansas/studies/qw/cyanobacteria)_
- USGS cyanotoxin sampling protocol:  _[http://pubs.usgs.gov/sir/2008/5038](http://pubs.usgs.gov/sir/2008/5038)_