Measuring Agrochemical Residue Levels in Fish Populations

Fish can be exposed to agrochemicals in two primary ways: through residues present in crops that are incorporated into fish food, and through exposure to water that is contaminated with agrocultural runoff. Typical bioaccumulation studies with livestock involve exposing animals to controlled doses of the chemical through feed or drinking water. However, fish populations present special challenges. Battelle partnered an unnamed company to develop new types of studies in order to help companies meet the new registration requirements.

For each chemical to be evaluated, we first look at how and where the chemical is used and the most likely routes of exposure for fish populations. Then we design a custom study in order to evaluate how the chemical is metabolized and how it accumulates in tissues. In feeding studies, we apply controlled doses of the chemical in fish food and measure the eventual tissue accumulation. Accumulation levels can then be checked against Acceptable Daily Intake guidelines to determine if the levels present a risk to human health if the fish is ingested at normal consumption levels. In metabolism studies, we evaluate how the chemical is broken down or excreted by fish.