The market for these tests is growing. The European Commission has identified endocrine disruptors as serious contaminants to be monitored and restricted under its Registration, Evaluation, Authorization and Restriction of Chemical (REACH) legislation and its Water Framework Directive. But both laws are short on key details. “They don’t say what an endocrine disruptor is or how to test it,” Lemkine says. Because of this lapse, WatchFrog is targeting its tests to OECD guidelines, which define hormone disruptors as chemicals that can disrupt the ability of a fish to produce eggs or change sex or prevent a tadpole from metamorphosing.
The U.S. Environmental Protection Agency (EPA) is already using WatchFrog’s tadpole model. To prioritize which of thousands of chemicals need toxicity testing, the agency’s ToxCast program uses computational tools and high-throughput testing to identify a signature for the types of chemicals that might be dangerous. The EPA then uses WatchFrog’s tadpole test as a middle step to discover which suspicious chemicals require expensive, time-consuming toxicology tests, says Kevin Crofton, acting deputy director of the EPA's National Center for Computational Toxicology.
Another EPA program, Pathfinder, is helping WatchFrog automate its tests for on-site use. Pathfinder funds developing technologies that target environmental and human health challenges. It helped WatchFrog develop the FrogBox, a device the size of a record turntable that uses cartridges containing tadpoles for continuous flow-through monitoring.
One target application is the outflow from water treatment centers. Treatment eradicates targeted chemicals but can generate harmful by-products. FrogBox’s ability to survey an ongoing stream will allow it to document hourly, daily, weekly or seasonal changes in pollutant levels.
The hospital outside of Paris is a typical target client. The 1.4-million-euro project, which will run for two to three years, will identify which effluent streams could be better treated. The idea is to develop a mobile lab at the hospital.
As in France, so it goes in the United States. The tadpoles and fish fry are “little sentinel animals,” Crofton says. “If you see a signal, it means, gee we’d better take a second look here.”
* Editor's Note (2/12/13): These sentences were edited after posting either to correct or clarify the original content.