Decoding Harmful Algal Blooms: Unraveling the Mystery
Interdisciplinary Science Approach for Harmful Algal Blooms and Algal Toxins
Harmful algal blooms (HABs) are a significant environmental concern due to their potential effects on health, ecosystems, and economies. Algal toxins, which are toxic compounds produced by certain species of cyanobacteria and algae, are commonly linked to these blooms. It's important to note that algal toxins can still be present even when a bloom is not visible, highlighting the need for ongoing monitoring and awareness. Ingestion or contact with these toxins can lead to a range of health effects including skin irritations and rashes, gastrointestinal symptoms, respiratory distress, and neurological effects. Pets and livestock can also be severely affected by algal toxins, which may lead to sudden illness or death after exposure to contaminated water.
Toxin Exposure and Effects
Humans, wildlife and fish can encounter algal toxins through contaminated water bodies, where harmful algal blooms release these toxins. Algal toxins can affect the behavior of both fish and wildlife, leading to adverse effects, including mortality. Prolonged exposure can result in enduring consequences for populations, potentially causing declines in species. To understand the potential health risks associated with toxin exposure, USGS studies are focused on:
- Investigating the occurrence (potential exposure) of algal toxins across the different surface water types.
- Identifying how humans and domestic animals may be exposed to toxins through drinking water, contaminated food, and recreational activities.
- Understanding the locations and methods by which fish and wildlife are affected by algal toxins and assessing the health impacts of toxin exposure on these species.
- Understanding the socioeconomic impact of exposure to HABs on fishing, tourism, and health.
Review of Harmful Algal Bloom Effects on Birds with Implications for Avian Wildlife in the Chesapeake Bay Region
Effects of Harmful Algal Bloom on Amphibians and Reptiles
Cyanotoxins in Inland Lakes of the United States: Occurrence and Potential Recreational Health Risks in the EPA National Lakes Assessment of 2007
Spatial and Temporal Variation in Microcystin Occurrence in Wadeable Streams in the Southeastern United States
Causes, Control, Fate, Prevention and Mitigation of Toxin Production
Algal blooms pose a significant environmental and economic challenge, contributing to the decline of fish and wildlife populations, affecting human health, and leading to the closure of vital recreational resources and economic impacts (e.g., fishing licenses, tourism, property values). While nutrients like nitrogen and phosphorus are well-known contributors to the growth of these blooms, it is crucial to recognize that they are not the only factors influencing algal bloom development. An abundance of nutrients does not automatically result in the production of harmful toxins. By understanding the specific factors that lead to harmful and toxic algal blooms, we can improve management strategies and prevention efforts, thereby reducing the need for costly treatments and emergency responses after a bloom occurs.
Current Research Questions
To tackle this issue, the USGS is focused on enhancing our understanding of the various elements that may contribute to the presence of algal toxins.
- How do abiotic factors and specific landscape features influence algal toxin dynamics and production?
- What intricate interactions between different microbes and environmental conditions could influence toxin production?
- What are the effects of various land-management practices on water clarity and toxin production?
- How do changing weather patterns and flood events impact oxygen content and other water-quality parameters related to blooms and toxin production in the long term?
- Can a geohistorical approach determine whether past blooms and toxin production are correlated with changes in temperature or precipitation?
- How can adaptive management practices effectively address and mitigate risks associated with algal toxins?
Analytical Toolbox
To address the complexities and unknowns in toxin production, new technologies and approaches are being developed to characterize algal bloom composition and function, help elucidate the complex interactions between algal species, their environment, and the effects on health and ecosystems.
- Targeted Toxin Analysis: Designed to detect and quantify specific toxins known to be present in a sample, these methods focus on a predetermined list of compounds.
- Non-Targeted Toxin Analysis: These methods are used to analyze complex samples without prior knowledge of the specific toxins present, aiming to identify as many compounds as possible.
- Microscopic Identification: Traditional method used to classify cyanobacteria species based on their morphological characteristics.
- “Omics”: Genomics, transcriptomics, proteomics, and metabolomics—offer powerful tools for understanding the complexities of algal blooms. These methods allow for an integrated view of how genetic, transcript, protein, and metabolic changes contribute to the behavior and impact of algal species in aquatic environments.
How Our Research is Being Used
1. Adaptive Management: Research on U.S. National Parks and U.S. Fish & Wildlife Service refuge lands is helping the agencies develop strategies to prevent algal blooms and toxin production, thereby minimizing toxin exposure and protecting ecosystems to maximize recreational use and safeguard fish and wildlife.
2. Freshwater Lake Research: Many people rely on the nation's largest lakes and reservoirs for recreation (e.g., fishing, boating, hunting, swimming), drinking water, and, in the case of the Great Lakes, international trade. It is critical to understand bloom and toxin production processes in these waters and translate lessons learned to the rest of the Country’s waters.
- Great Lakes: To support the understanding on algal toxin dynamic, particularly in Lake Erie, USGS is working with NOAA and the University of Michigan to characterize a large suite of algal toxins through targeted and non-targeted methods and examine relations to associated microbial community structure. Previous efforts included testing the role of nutrients and metals as limiters of algal growth and toxin production in Lake Erie and Lake Michigan.
- Lake Okeechobee: A report on the 2018 harmful algal bloom in Lake Okeechobee was found to have an estimated economic effect of 5.5 million dollars in foregone recreation and another 2.3 million dollars in property value reductions; working with partners such as the Army Corps of Engineers, USGS helps determine values associated with mitigation technology. Other research efforts in Lake Okeechobee are measuring the relations among algal blooms and environmental variables that may influence their growth.
- Lake Tahoe: An ongoing study in Lake Tahoe is investigating the occurrence of cyanobacteria and toxins along the lakeshore as directed by US Congress to better understand processes that may be driving a loss in lake clarity.
3. Cyanobacteria Assessment Network (CyAN): In collaboration with NASA, EPA, and NOAA, CyAN offers daily, near real-time measurements of cyanobacteria blooms in over 2,000 of the nation's largest lakes and reservoirs using satellite imagery. An analysis of the value of an early warning system like CyAN was estimated to provide between 565 thousand dollars and 2.3 million dollars in economic benefits for the state of Kansas alone in avoided health effects and foregone recreation opportunities.
4. Drinking Water: Consumers rely on healthy drinking water for everyday life. Work is being done to evaluate the presence of cyanotoxins in drinking water sources and improve treatment options at municipal and personal scales.
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A Review of Algal Toxin Exposures on Reserved Federal Lands and Among Trust Species in the United States
Phytoplankton Community Interactions and Cyanotoxin Mixtures in Three Recurring Surface Blooms Within One Lake
Nutrient Management for Harmful Algal Blooms
Understanding Algal Bloom Dynamics in Lake Okeechobee
What's It Worth? Estimating the Potential Value of Early Warning of Cyanobacterial Harmful Algal Blooms
Agencies Collaborate, Develop a Cyanobacteria Network
Tapwater Exposures, Effects Potential, and Residential Risk Management in Northern Plains Nations
Bottled Water Contaminant Exposures and Potential Human Effects
Exposures and Potential Health Implications of Contaminant Mixtures in Linked Source Water, Finished Drinking Water, and Tapwater from public-supply drinking water systems in Minneapolis/St. Paul area
Follow the Toxins and Harmful Algal Blooms Science Team
Harmful algal blooms (HABs) are a significant environmental concern due to their potential effects on health, ecosystems, and economies. Algal toxins, which are toxic compounds produced by certain species of cyanobacteria and algae, are commonly linked to these blooms. It's important to note that algal toxins can still be present even when a bloom is not visible, highlighting the need for ongoing monitoring and awareness. Ingestion or contact with these toxins can lead to a range of health effects including skin irritations and rashes, gastrointestinal symptoms, respiratory distress, and neurological effects. Pets and livestock can also be severely affected by algal toxins, which may lead to sudden illness or death after exposure to contaminated water.
Toxin Exposure and Effects
Humans, wildlife and fish can encounter algal toxins through contaminated water bodies, where harmful algal blooms release these toxins. Algal toxins can affect the behavior of both fish and wildlife, leading to adverse effects, including mortality. Prolonged exposure can result in enduring consequences for populations, potentially causing declines in species. To understand the potential health risks associated with toxin exposure, USGS studies are focused on:
- Investigating the occurrence (potential exposure) of algal toxins across the different surface water types.
- Identifying how humans and domestic animals may be exposed to toxins through drinking water, contaminated food, and recreational activities.
- Understanding the locations and methods by which fish and wildlife are affected by algal toxins and assessing the health impacts of toxin exposure on these species.
- Understanding the socioeconomic impact of exposure to HABs on fishing, tourism, and health.
Review of Harmful Algal Bloom Effects on Birds with Implications for Avian Wildlife in the Chesapeake Bay Region
Effects of Harmful Algal Bloom on Amphibians and Reptiles
Cyanotoxins in Inland Lakes of the United States: Occurrence and Potential Recreational Health Risks in the EPA National Lakes Assessment of 2007
Spatial and Temporal Variation in Microcystin Occurrence in Wadeable Streams in the Southeastern United States
Causes, Control, Fate, Prevention and Mitigation of Toxin Production
Algal blooms pose a significant environmental and economic challenge, contributing to the decline of fish and wildlife populations, affecting human health, and leading to the closure of vital recreational resources and economic impacts (e.g., fishing licenses, tourism, property values). While nutrients like nitrogen and phosphorus are well-known contributors to the growth of these blooms, it is crucial to recognize that they are not the only factors influencing algal bloom development. An abundance of nutrients does not automatically result in the production of harmful toxins. By understanding the specific factors that lead to harmful and toxic algal blooms, we can improve management strategies and prevention efforts, thereby reducing the need for costly treatments and emergency responses after a bloom occurs.
Current Research Questions
To tackle this issue, the USGS is focused on enhancing our understanding of the various elements that may contribute to the presence of algal toxins.
- How do abiotic factors and specific landscape features influence algal toxin dynamics and production?
- What intricate interactions between different microbes and environmental conditions could influence toxin production?
- What are the effects of various land-management practices on water clarity and toxin production?
- How do changing weather patterns and flood events impact oxygen content and other water-quality parameters related to blooms and toxin production in the long term?
- Can a geohistorical approach determine whether past blooms and toxin production are correlated with changes in temperature or precipitation?
- How can adaptive management practices effectively address and mitigate risks associated with algal toxins?
Analytical Toolbox
To address the complexities and unknowns in toxin production, new technologies and approaches are being developed to characterize algal bloom composition and function, help elucidate the complex interactions between algal species, their environment, and the effects on health and ecosystems.
- Targeted Toxin Analysis: Designed to detect and quantify specific toxins known to be present in a sample, these methods focus on a predetermined list of compounds.
- Non-Targeted Toxin Analysis: These methods are used to analyze complex samples without prior knowledge of the specific toxins present, aiming to identify as many compounds as possible.
- Microscopic Identification: Traditional method used to classify cyanobacteria species based on their morphological characteristics.
- “Omics”: Genomics, transcriptomics, proteomics, and metabolomics—offer powerful tools for understanding the complexities of algal blooms. These methods allow for an integrated view of how genetic, transcript, protein, and metabolic changes contribute to the behavior and impact of algal species in aquatic environments.
How Our Research is Being Used
1. Adaptive Management: Research on U.S. National Parks and U.S. Fish & Wildlife Service refuge lands is helping the agencies develop strategies to prevent algal blooms and toxin production, thereby minimizing toxin exposure and protecting ecosystems to maximize recreational use and safeguard fish and wildlife.
2. Freshwater Lake Research: Many people rely on the nation's largest lakes and reservoirs for recreation (e.g., fishing, boating, hunting, swimming), drinking water, and, in the case of the Great Lakes, international trade. It is critical to understand bloom and toxin production processes in these waters and translate lessons learned to the rest of the Country’s waters.
- Great Lakes: To support the understanding on algal toxin dynamic, particularly in Lake Erie, USGS is working with NOAA and the University of Michigan to characterize a large suite of algal toxins through targeted and non-targeted methods and examine relations to associated microbial community structure. Previous efforts included testing the role of nutrients and metals as limiters of algal growth and toxin production in Lake Erie and Lake Michigan.
- Lake Okeechobee: A report on the 2018 harmful algal bloom in Lake Okeechobee was found to have an estimated economic effect of 5.5 million dollars in foregone recreation and another 2.3 million dollars in property value reductions; working with partners such as the Army Corps of Engineers, USGS helps determine values associated with mitigation technology. Other research efforts in Lake Okeechobee are measuring the relations among algal blooms and environmental variables that may influence their growth.
- Lake Tahoe: An ongoing study in Lake Tahoe is investigating the occurrence of cyanobacteria and toxins along the lakeshore as directed by US Congress to better understand processes that may be driving a loss in lake clarity.
3. Cyanobacteria Assessment Network (CyAN): In collaboration with NASA, EPA, and NOAA, CyAN offers daily, near real-time measurements of cyanobacteria blooms in over 2,000 of the nation's largest lakes and reservoirs using satellite imagery. An analysis of the value of an early warning system like CyAN was estimated to provide between 565 thousand dollars and 2.3 million dollars in economic benefits for the state of Kansas alone in avoided health effects and foregone recreation opportunities.
4. Drinking Water: Consumers rely on healthy drinking water for everyday life. Work is being done to evaluate the presence of cyanotoxins in drinking water sources and improve treatment options at municipal and personal scales.