Development and Preliminary Validation of an Amphibian Lifecycle Test Method for Monitoring Endocrine Disruption

Concerns regarding both the presence of endocrine disruptors in food, water, or other environmental media as well as the potential risk they pose to humans and wildlife have been growing in recent years. Passage of the Food Quality Protection Act and Amendments to the Safe Drinking Water Act reflected these concerns and required the U.S. Environmental Protection Agency (EPA) to develop a screening program, using appropriate validated test systems and other scientifically relevant information, to determine whether certain substances may have an endocrine effect in wildlife and humans. This research project will result in the validation of an assay that tests substances that might disturb reproductive and developmental processes during the lifecycle of animals by interfering with the endocrine system. The primary goal of the proposed research is to standardize, validate, and commercialize an amphibian lifecycle model using Xenopus as a system for evaluation of endocrine-disrupting chemicals (EDCs) found in the workplace or the environment. Specifically, Fort Environmental Laboratories, Inc., will standardize and validate an X. tropicalis assay designed to evaluate the effect of EDCs on various aspects of the amphibian lifecycle by conducting studies with a series of known mammalian EDCs, compounds found to be inactive, and chemicals with unknown activity. Because none of the currently developed EDC test systems are capable of specifically addressing lifecycle effects in amphibians and the Endocrine Disruptor Screening Program developed for EPA by the Endocrine Screening and Testing Committee, the successful completion of this amphibian lifecycle model will provide the scientific community with a non-mammalian, cost-effective, rapid, reliable method of prescreening EDCs. The ability to rapidly and cost-effectively screen for and evaluate the mechanisms of EDCs is an attractive alternative to the current laborious and expensive testing systems used today. Increasing concerns over the widespread finding of EDCs in the environment have dramatically increased the need for standardized assays, such as the Xenopus lifecycle model, because no other assay of this type is available today. Current estimates indicate that nearly 50,000 chemicals in the United States may require EDC testing with models such as the amphibian lifecycle assay. Overall, this volume of work has the potential of generating approximately $125 billion during the next 10¿15 years. Realistically, it is anticipated that based on the high volume of work generated by this need for cost-effective testing of chemicals, revenue of more than $5 million could be generated during the next 2 years, and more than $25 billion during the next 10 years.