You may notice a green, red or brown film on your favorite boating or swimming area in the summer. This coloring could mean that the water is affected by harmful algal blooms. USGS scientists Dr. Barry Rosen, Dr. Jennifer Graham and Dr.
New Study on Cyanotoxins in Lakes and Reservoirs Provides Insights into Assessing Health Risks
Completed
By Environmental Health Program
May 31, 2016
Cyanobacterial Accumulation at Binder Lake, Iowa
Close Up of a Cyanobacteria Bloom on Elysian Lake, Minnesota
Occurrence of Microcystins in Lakes in the Contiguous US 48 states
Newly published study provides new evidence of the widespread occurrence of cyanotoxins in lakes and reservoirs of the United States and offers new insights into measures used for assessing potential recreational health risks.
Sources/Usage: Public Domain. View Media Details
In 2007, scientists completed the largest survey of cyanotoxins in the Nation's lakes. Scientists sampled 1,161 lakes across the Nation for cyanotoxins, cyanobacteria abundance, and chlorophyll-a—the three measures used by the World Health Organization (WHO) to determine associated human health risks in recreational waters ranging from skin rashes and nausea to liver failure and respiratory distress. The scientists measured several cyanotoxins including cylindrospermopsins, microcystins, and saxitoxins.
Although cyanotoxin occurrence in lakes was commonly perceived to have a local or regional occurrence, this study found multiple classes of cyanotoxins were present in lakes and reservoirs in diverse settings across the United States. Cyanobacteria were present in 98 percent of the lakes studied. Potential cylindrospermopsin-, microcystin-, and saxitoxin-producing cyanobacteria were present in 81, 67, 95, and 79 percent of samples, respectively; however, the toxins were present in 4.0, 32, and 7.7 percent, respectively, which indicated that cyanobacterial abundance can over-predict microcystin and other cyanotoxin exposure risk.
Sources/Usage: Public Domain. View Media Details
The WHO moderate and high risk thresholds for microcystins, cyanobacteria abundance, and total chlorophyll were exceeded in 1.1, 27, and 44 percent of samples, respectively. There was direct agreement between the three WHO measures used for recreational risk on the basis of microcystin exposure in only 27 percent of the samples measured in this study, which indicated that algal abundance and chlorophyll-a concentrations may over-predict recreational risks associated with cyanotoxins. The lack of similarity among the WHO thresholds was expected because chlorophyll is common amongst all algae and not all algae produce microcystins.
There is increasing public recognition that cyanobacteria and their toxins can have a toxic effect on water use and quality. Some cyanobacteria produce toxins that can kill wildlife and domestic animals and cause illness or death in humans through exposure to contaminated freshwater or by the consumption of contaminated drinking water, fish, or shellfish. The discovery, in 2014, that the City of Toledo, Ohio, water supply was contaminated by microcystins drew national attention to the potential vulnerabilities of our water resources to toxins formed in association with harmful algal blooms.
Sources/Usage: Some content may have restrictions. View Media Details
Typically, studies done for harmful algal bloom event response programs only measure microcystins or algal abundance and less frequently chlorophyll or other cyanotoxins, whereas ambient monitoring programs usually focus on chlorophyll and algal abundance measures to assess health risks. This study demonstrates that monitoring for chlorophyll is not a reliable indicator of the presence of microcystins; monitoring for microcystins is not a reliable indicator of the presence of saxitoxins and cylindrospermopsins; and that microcystins are not the only toxins for consideration of risk to humans and animals.
This study provides information needed to understand the relation between current (2016) measures of potential recreational health risks of cyanohabs and highlights the importance of selecting measurements that closely relate to monitoring objectives. This assessment was performed as part of a broader U.S. Geological Survey (USGS) research project on cyanotoxins. The broader research goals include determination of factors related to cyanotoxin production and factors that may influence or create new environmental pathways of cyanobacteria that lead to human and ecological exposure and adverse outcomes.
This research was funded by the USGS Ecosystems Mission Area’s Environmental Health Program (Contaminant Biology and Toxic Substances Hydrology) and National Water Quality Assessment Programs, and U.S. Environmental Protection Agency's Office of Wetlands, Oceans, and Watersheds and National Health and Environmental Effects Research.
Below are other science projects associated with this project.
Toxins and Harmful Algal Blooms Science Team
The team develops advanced methods to study factors driving algal toxin production, how and where wildlife or humans are exposed to toxins, and ecotoxicology. That information is used to develop decision tools to understand if toxin exposure leads to adverse health effects in order to protect human and wildlife health.
USGS Scientist Receives Award for Assistance with National Wetlands Assessment
U.S. Geological Survey (USGS) scientist Dr. Keith A. Loftin received the U.S. Environmental Protection Agency (EPA) Office of Water's Achievement in Science and Technology Award for his contributions to the National Wetlands Condition Assessment.
Nitrate Addition Enhances Arsenic Immobilization in Groundwater
The addition of nitrate in a low oxygen groundwater resulted in the immobilization of naturally occurring dissolved arsenic and the conversion of nitrate to innocuous nitrogen gas.
New Study Measures Crop Bactericide, Nitrapyrin, in Iowa Streams
First-ever reconnaissance study documents the off-field transport of nitrapyrin — a nitrification inhibitor applied with fertilizers as a bactericide to kill natural soil bacteria for the purpose of increasing crop yields — to adjacent streams. This study is the first step in understanding the transport, occurrence, and potential effects of nitrapyrin or similar compounds on nitrogen processing in...
Nutrients in Dust from the Sahara Desert cause Microbial Blooms on the East Coast of the United States
Saharan dust nutrients, particularly iron, deposited episodically in tropical marine waters stimulate marine microbial bloom growth and change microbial community structure.
USGS Scientists Measure New Bacterial Nitrogen Removal Process in Groundwater
For the first time, U.S. Geological Survey (USGS), Virginia Institute of Marine Science, and the University of Connecticut scientists have detected active anammox bacteria in groundwater.
Cyanobacterial (Blue-Green Algal) Blooms: Tastes, Odors, and Toxins
Freshwater and marine harmful algal blooms (HABs) can occur anytime water use is impaired due to excessive accumulations of algae. In freshwater, the majority of HABs are caused by cyanobacteria (also called blue-green algae). Cyanobacteria cause a multitude of water-quality concerns, including the potential to produce taste-and-odor causing compounds and toxins that are potent enough to poison...
Importance of Lake Sediments in Removal of Cyanobacteria, Viruses, and Dissolved Organic Carbon
U.S. Geological Survey (USGS) scientists determined that the colmation layer (top 25 centimeters of lake sediments) was highly effective in removing cyanobacteria, viruses, and dissolved organic carbon during water passage through the lake bottom to aquifer sediments.
U.S. Geological Survey Scientists Complete First Systematic Regional Survey of Algal Toxins in Streams of the Southeastern United States
U.S. Geological Survey (USGS) scientists detected microcystin—an algal toxin—in 39 percent of 75 streams assessed in the southeastern United States. These results will inform and become part of a larger, systematic national survey of algal toxins in small streams of the United States.
Remote Sensing Provides a National View of Cyanobacteria Blooms
Four Federal agencies, including the U.S. Geological Survey (USGS), are collaborating to transform satellite data into information managers can use to protect ecological and human health from freshwater contaminated by harmful algal blooms.
Algal Blooms Consistently Produce Complex Mixtures of Cyanotoxins and Co-Occur with Taste-and-Odor Causing Compounds in 23 Midwestern Lakes
U.S. Geological Survey (USGS) scientists studying the effects of harmful algal blooms on lake water quality found that blooms of blue-green algae (cyanobacteria) in Midwestern lakes produced mixtures of cyanotoxins and taste-and-odor causing compounds, which co-occurred in lake water samples. Cyanotoxins can cause allergic and/or respiratory issues, attack the liver and kidneys, or affect the...
Below are multimedia items associated with this project.
Slimy Summer Swimming: Harmful Algal Blooms in Lakes, Rivers and Streams
You may notice a green, red or brown film on your favorite boating or swimming area in the summer. This coloring could mean that the water is affected by harmful algal blooms. USGS scientists Dr. Barry Rosen, Dr. Jennifer Graham and Dr.
Newly published study provides new evidence of the widespread occurrence of cyanotoxins in lakes and reservoirs of the United States and offers new insights into measures used for assessing potential recreational health risks.
Sources/Usage: Public Domain. View Media Details
In 2007, scientists completed the largest survey of cyanotoxins in the Nation's lakes. Scientists sampled 1,161 lakes across the Nation for cyanotoxins, cyanobacteria abundance, and chlorophyll-a—the three measures used by the World Health Organization (WHO) to determine associated human health risks in recreational waters ranging from skin rashes and nausea to liver failure and respiratory distress. The scientists measured several cyanotoxins including cylindrospermopsins, microcystins, and saxitoxins.
Although cyanotoxin occurrence in lakes was commonly perceived to have a local or regional occurrence, this study found multiple classes of cyanotoxins were present in lakes and reservoirs in diverse settings across the United States. Cyanobacteria were present in 98 percent of the lakes studied. Potential cylindrospermopsin-, microcystin-, and saxitoxin-producing cyanobacteria were present in 81, 67, 95, and 79 percent of samples, respectively; however, the toxins were present in 4.0, 32, and 7.7 percent, respectively, which indicated that cyanobacterial abundance can over-predict microcystin and other cyanotoxin exposure risk.
Sources/Usage: Public Domain. View Media Details
The WHO moderate and high risk thresholds for microcystins, cyanobacteria abundance, and total chlorophyll were exceeded in 1.1, 27, and 44 percent of samples, respectively. There was direct agreement between the three WHO measures used for recreational risk on the basis of microcystin exposure in only 27 percent of the samples measured in this study, which indicated that algal abundance and chlorophyll-a concentrations may over-predict recreational risks associated with cyanotoxins. The lack of similarity among the WHO thresholds was expected because chlorophyll is common amongst all algae and not all algae produce microcystins.
There is increasing public recognition that cyanobacteria and their toxins can have a toxic effect on water use and quality. Some cyanobacteria produce toxins that can kill wildlife and domestic animals and cause illness or death in humans through exposure to contaminated freshwater or by the consumption of contaminated drinking water, fish, or shellfish. The discovery, in 2014, that the City of Toledo, Ohio, water supply was contaminated by microcystins drew national attention to the potential vulnerabilities of our water resources to toxins formed in association with harmful algal blooms.
Sources/Usage: Some content may have restrictions. View Media Details
Typically, studies done for harmful algal bloom event response programs only measure microcystins or algal abundance and less frequently chlorophyll or other cyanotoxins, whereas ambient monitoring programs usually focus on chlorophyll and algal abundance measures to assess health risks. This study demonstrates that monitoring for chlorophyll is not a reliable indicator of the presence of microcystins; monitoring for microcystins is not a reliable indicator of the presence of saxitoxins and cylindrospermopsins; and that microcystins are not the only toxins for consideration of risk to humans and animals.
This study provides information needed to understand the relation between current (2016) measures of potential recreational health risks of cyanohabs and highlights the importance of selecting measurements that closely relate to monitoring objectives. This assessment was performed as part of a broader U.S. Geological Survey (USGS) research project on cyanotoxins. The broader research goals include determination of factors related to cyanotoxin production and factors that may influence or create new environmental pathways of cyanobacteria that lead to human and ecological exposure and adverse outcomes.
This research was funded by the USGS Ecosystems Mission Area’s Environmental Health Program (Contaminant Biology and Toxic Substances Hydrology) and National Water Quality Assessment Programs, and U.S. Environmental Protection Agency's Office of Wetlands, Oceans, and Watersheds and National Health and Environmental Effects Research.
Below are other science projects associated with this project.
Toxins and Harmful Algal Blooms Science Team
The team develops advanced methods to study factors driving algal toxin production, how and where wildlife or humans are exposed to toxins, and ecotoxicology. That information is used to develop decision tools to understand if toxin exposure leads to adverse health effects in order to protect human and wildlife health.
USGS Scientist Receives Award for Assistance with National Wetlands Assessment
U.S. Geological Survey (USGS) scientist Dr. Keith A. Loftin received the U.S. Environmental Protection Agency (EPA) Office of Water's Achievement in Science and Technology Award for his contributions to the National Wetlands Condition Assessment.
Nitrate Addition Enhances Arsenic Immobilization in Groundwater
The addition of nitrate in a low oxygen groundwater resulted in the immobilization of naturally occurring dissolved arsenic and the conversion of nitrate to innocuous nitrogen gas.
New Study Measures Crop Bactericide, Nitrapyrin, in Iowa Streams
First-ever reconnaissance study documents the off-field transport of nitrapyrin — a nitrification inhibitor applied with fertilizers as a bactericide to kill natural soil bacteria for the purpose of increasing crop yields — to adjacent streams. This study is the first step in understanding the transport, occurrence, and potential effects of nitrapyrin or similar compounds on nitrogen processing in...
Nutrients in Dust from the Sahara Desert cause Microbial Blooms on the East Coast of the United States
Saharan dust nutrients, particularly iron, deposited episodically in tropical marine waters stimulate marine microbial bloom growth and change microbial community structure.
USGS Scientists Measure New Bacterial Nitrogen Removal Process in Groundwater
For the first time, U.S. Geological Survey (USGS), Virginia Institute of Marine Science, and the University of Connecticut scientists have detected active anammox bacteria in groundwater.
Cyanobacterial (Blue-Green Algal) Blooms: Tastes, Odors, and Toxins
Freshwater and marine harmful algal blooms (HABs) can occur anytime water use is impaired due to excessive accumulations of algae. In freshwater, the majority of HABs are caused by cyanobacteria (also called blue-green algae). Cyanobacteria cause a multitude of water-quality concerns, including the potential to produce taste-and-odor causing compounds and toxins that are potent enough to poison...
Importance of Lake Sediments in Removal of Cyanobacteria, Viruses, and Dissolved Organic Carbon
U.S. Geological Survey (USGS) scientists determined that the colmation layer (top 25 centimeters of lake sediments) was highly effective in removing cyanobacteria, viruses, and dissolved organic carbon during water passage through the lake bottom to aquifer sediments.
U.S. Geological Survey Scientists Complete First Systematic Regional Survey of Algal Toxins in Streams of the Southeastern United States
U.S. Geological Survey (USGS) scientists detected microcystin—an algal toxin—in 39 percent of 75 streams assessed in the southeastern United States. These results will inform and become part of a larger, systematic national survey of algal toxins in small streams of the United States.
Remote Sensing Provides a National View of Cyanobacteria Blooms
Four Federal agencies, including the U.S. Geological Survey (USGS), are collaborating to transform satellite data into information managers can use to protect ecological and human health from freshwater contaminated by harmful algal blooms.
Algal Blooms Consistently Produce Complex Mixtures of Cyanotoxins and Co-Occur with Taste-and-Odor Causing Compounds in 23 Midwestern Lakes
U.S. Geological Survey (USGS) scientists studying the effects of harmful algal blooms on lake water quality found that blooms of blue-green algae (cyanobacteria) in Midwestern lakes produced mixtures of cyanotoxins and taste-and-odor causing compounds, which co-occurred in lake water samples. Cyanotoxins can cause allergic and/or respiratory issues, attack the liver and kidneys, or affect the...
Below are multimedia items associated with this project.
Slimy Summer Swimming: Harmful Algal Blooms in Lakes, Rivers and Streams
You may notice a green, red or brown film on your favorite boating or swimming area in the summer. This coloring could mean that the water is affected by harmful algal blooms. USGS scientists Dr. Barry Rosen, Dr. Jennifer Graham and Dr.
You may notice a green, red or brown film on your favorite boating or swimming area in the summer. This coloring could mean that the water is affected by harmful algal blooms. USGS scientists Dr. Barry Rosen, Dr. Jennifer Graham and Dr.