Superfund Research Program
Arrays to Measure Endocrine Disruption in Fish
Project Leader: Patrick Larkin
Grant Number: R43ES011882
Funding Period: Phase I: 2002-2004
Endocrine disruption refers to the disruption of normal endocrine systems by exposure to environmental chemicals that mimic hormones, or alter the synthesis, metabolism, and activity of hormones. Widespread public concern about chemicals in the environment that may act as endocrine disruptors had mandated a concerted effort to monitor the cleanup of Superfund sites contaminated with endocrine disrupting compounds (EDCs) and to determine the extent of exposure and the physiological consequences in fish.
Given the profound environmental impact and direct and derivative human health consequences caused by EDCs, the US Government has mandated the Environmental Protection Agency (EPA) to develop assay systems for more than 70,000 chemicals, including EDCs. Currently, there is no single commercial test for these compounds that is reliable and robust for these chemicals. The screening assays that are currently commercially available either fail to report accurately on the physiological outcomes of exposures or are expensive and too lengthy to be employed routinely as monitoring tools.
The goal of this project is to develop an array that is responsive to several EDCs in largemouth bass, a fish that is a sensitive indicator of endocrine disruption. Researchers plan to define gene expression fingerprints specific to these EDCs and use them to monitor the presence or disappearance (indicating successful cleanup) of endocrine modulating chemicals at a specific Superfund site, namely Lake Apopka and its surrounding muck farms.
More broadly, researchers on this project are working to develop an array technology to identify and monitor bio-available EDC levels, initially in Superfund sites and ultimately as a standard testing system for research and commercial systems that use compounds that can disrupt the endocrine systems. This array technology will be applied in an effort to provide an assay that is relatively easy to perform, requires only short exposure times and portrays accurately the events that happen at the molecular level. An assay system that can monitor the impact of many of these EDC compounds is also appropriate to the problem EPA is trying to solve, since hundreds of thousands of genes can be spotted onto a single chip. The array fabrication process can be automated, which may allow for mass production at a reasonable price. Researchers also believe the assay system can be extended to other fish species relatively easily, extending its commercial and environmental value.