In an attempt to explain the etiology of frog deformities and population declines, many possible causative factors have been examined, including the input of synthetic chemicals into aquatic systems, where frogs spend much of their lives, including their entire developmental stages. This study focused on surveying wetlands in southwestern Michigan that are influenced by agricultural run-off or urban and industrial inputs for deformities in green frogs. Of the 1445 green frogs examined in 1998, only 4 (0.28%) exhibited morphological deformities. Water, sediment and tissue from frog eggs, tadpoles, juveniles, and adults were analyzed for organochlorine (OC) insecticides, polychlorinated biphenyls (PCBs), metals, and triazine herbicides by use of traditional instrumental analysis for most compounds and by Enzyme-Linked Immunosorbent Assay (ELISA) for triazine analysis. Sample extracts were also assayed for their estrogenic and dioxin-like activities using recombinant cell lines. Overall, low concentrations were observed in the frogs and their habitats. No correlation between deformities and chemicals could be made due to the low deformity rate in the region.