Strategies for assessing the implications of malformed frogs for environmental health

The recent increase in the incidence of deformities among natural frog popu lations has raised concern about the state of the environment and the possi ble impact of unidentified causative agents on the health of wildlife and h uman populations. An open workshop on Strategies for Assessing the Implicat ions of Malformed Frogs for Environmental Health was convened on 4-5 Decemb er 1997 at the National Institute of Environmental Health Sciences in Resea rch Triangle Park, North Carolina. The purpose of the workshop was to share information among a multidisciplinary group with scientific interest and r esponsibility for human and environmental health at the federal and state l evel. Discussions highlighted possible causes and recent findings directly related to frog deformities and provided insight into problems and strategi es applicable to continuing investigation in several areas. Possible causes of the deformities were evaluated in terms of diagnostics performed on fie ld amphibians, biologic mechanisms that can lead to the types of malformati ons observed, and parallel laboratory and field studies. Hydrogeochemistry must be more integrated into environmental toxicology because of the pivota l role of the aquatic environment and the importance of faces and transport relative to any potential exposure. There is no indication of whether ther e may be a human health factor associated with the deformities. However, th e possibility that causal agents may be waterborne indicates a need to iden tify the relevant factors and establish the relationship between environmen tal and human health in terms of hazard assessment.