Framework Developed to Evaluate the Practicality of Effects-Directed Analyses to Identify Endocrine Active Chemicals in Complex Environmental Sample Mixtures

Science Center Objects

An effects-directed analyses (EDA) framework for endocrine active chemicals was developed to help decision makers quickly evaluate the efficacy and practicality of an EDA approach in waste and surface waters and how adjustments could be made to increase its success.

Scientist sitting next to a biological safety cabinet in a laboratory

A U.S. Geological Survey scientist in the cell bioassay laboratory at Columbia Environmental Research Center. Scientists optimized existing endocrine active chemical screening tests to improve their precision, accuracy, and ability to screen more samples in a shorter time-frame.

(Credit: Abigail Nicole Henke, U.S. Geological Survey, Columbia Environmental Research Center. Public domain.)

Effects‐directed analysis (EDA) is a technique utilized to isolate and identify biologically active components, such as endocrine‐active chemicals (EACs), from complex mixtures. Understanding which EACs elicit an adverse response in fish, wildlife, and humans is a challenge because most environmental exposures involve complex mixtures of chemicals, and it is difficult to isolate and identify the active agents. EDA identifies the biologically active agents from various fractions of a sample until the single chemical (or class of chemicals) that elicit a response is determined. EDA can guide the identification of the EAC that results in a response and can help rule out the EACs not responsible for the observed biological activity or response.

In a typical EDA for waste or surface water, large volumes of water are required because concentrations of EACs are typically low and near instrument detection limits. The sampling devices and laboratory space needed can present challenges and render this technique impractical. Therefore, the U.S. Geological Survey developed a representative EDA framework based on previous EDA research. This new framework is relevant to existing EAC concentrations, limits of quantitation for various laboratory analytical techniques, and the sensitivity of commonly used bioassays. The framework was designed to help decision makers to quickly evaluate the efficacy and practicality of an EDA approach and how adjustments, such as adjusting sample volume, could increase success.  

Huron River at Milan, OH

Large volumes of surface water are typically needed for an effects-directed analysis (EDA)

(Public domain.)

The Environmental Health Program (Contaminants Biology and Toxic Substances Hydrology) of the U.S. Geological Survey Ecosystems Mission Area supported this study.