Toxins and Harmful Algal Blooms Science Team

Cyanobacterial blooms, such as the one shown that occurred in 2016 on Lake Okeechobee, Florida, can release toxins. (Credit: Nicholas Aumen, US Geological Survey. Public domain.)

Algal blooms frequently occur in our Nation's water resources and can cause economic, ecologic, and human health concerns. Algal blooms often contain cyanobacteria and other microorganisms, which can produce natural toxins. Yet, the actual health threats posed to the public, pets, livestock, and wildlife by these toxins in water resources used for recreation and drinking water remain poorly understood. Consequently, in order to be protective from potential health risks, rapid decisions are often made by land managers, public utilities and others to limit access to water resources for recreation or drinking water. These decisions are often based largely on a perception of potential risk.

The U.S. Geological Survey’s (USGS) Toxins and Harmful Algal Blooms Research Team works with multiple stakeholders to quantify toxin exposure and effects, identify hazards and vulnerabilities, develop tools to quantify and forecast toxin occurrence and exposure, and estimate socioeconomic impacts. Knowledge gained is used to identify actual versus perceived health risks posed by natural toxins. The team’s approach for understanding health impacts of algal toxins on humans and animals is a sequential process where each step informs the next in the laboratory and in the field. This approach involves teams of USGS scientists working at field sites across the United States, and in collaboration with other scientists to address human health concerns.

Current Science Activities

• Development of methods for measuring cyanotoxins in fish tissues

• Determining the effects of cyanotoxins in fish, including, toxicity, cyanotoxin induced endocrine disruption, sublethal effects, and immunomodulation effects

• Determine bioaccessibility of cyanotoxins from ambient, finished drinking water, and raw and cooked fish in simulated mammalian digestive systems

• Dose-dependent animal toxicity studies for cyanotoxins and in relation to health advisory thresholds

• Nitrogen limitation, toxin synthesis potential, and toxicity of cyanobacterial populations

• Biomarkers and cellular response to acute and chronic cyanotoxin exposure and potential proactive response measures

• Evaluation of commercial personal drinking water purifiers for toxin removal

• Cyanotoxin and algal blooms related health impacts on reserved Federal lands and U.S. Trust species

• The response of harmful algae to atmospheric stimuli and implication for ecosystem and human health