Published on the Web 2/23/2009.
Growth and survival of northern leopard frog (Rana pipiens) tadpoles exposed to two common pesticides†
Article first published online: 9 DEC 2009
Copyright © 2009 SETAC
Environmental Toxicology and Chemistry
Volume 28, Issue 7, pages 1469–1474, July 2009
How to Cite
Shenoy, K., Cunningham, B. T., Enfroe, J. W. R. and Crowley, P. H. (2009), Growth and survival of northern leopard frog (Rana pipiens) tadpoles exposed to two common pesticides. Environmental Toxicology and Chemistry, 28: 1469–1474. doi: 10.1897/08-306.1
- Issue published online: 9 DEC 2009
- Article first published online: 9 DEC 2009
- Manuscript Accepted: 12 JAN 2009
- Manuscript Received: 2 JUL 2008
- Aquatic pollution;
- Amphibian decline
Aquatic pollution is an important factor implicated in global amphibian declines. Often amphibians are exposed to sublethal levels of agrochemicals continuously throughout their larval period either because of application regimes or persistence of the chemicals in the larvae's environment. Although most studies have examined the effects of one-time or short-term exposure to contaminants on amphibian larvae, few have investigated the implications of continuous exposure over a substantial interval during larval development. We examined the effects of continuous exposure to environmentally relevant concentrations of two common pesticides—endosulfan (0.2, 1, and 5 μg/L) and mancozeb (16, 80, and 400 μg/L)—on the growth and survival of leopard frog tadpoles. The concentrations used are comparable to those estimated to be found in waterbodies near agricultural fields. The exposure period was seven weeks. Mortality was recorded daily, and length was measured photographically once before and twice during the exposure period. Both chemicals greatly reduced survival at these concentrations. Hazard ratios were significantly positive for all treatments. Growth rates of tadpoles exposed to endosulfan were not significantly reduced, but exposure to all three levels of mancozeb resulted in reduced growth rates. These results underscore the importance of further investigation into the effects of endosulfan and mancozeb on environmental and wildlife health.