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Biological Methods and Manual Development

EPA scientists conduct research to develop and evaluate analytical methods for the identification, enumeration, and evaluation of aquatic organisms exposed to environmental stressors and to correlate exposures with effects on chemical and biological indicators. Environmental measurements are required to determine the quality of ambient waters and the character of environmental stressors. Possible environmental stressors include chemical pollutants; microbes and pathogens; physical agents, such as land use; and processes, such as alteration of wildlife habitat.

EPA’s scientists prepare and update field and laboratory protocols and methods for the following stream and source monitoring indicators: fish, macroinvertebrates, periphyton, zooplankton, functional ecosystem indicators, water and sediment toxicity, and fish tissue contaminants. They also provide technical assistance to states and EPA regions on the implementation and interpretation of these manuals. 

Field Methods

Toxicity and Contaminant Methods