You are here:
Quantifying Amphibian Pesticide Body Burdens for Active Ingredients Versus Formulations Through Dermal Exposure
Citation:
VanMeter, R., D. Glinski, AND Tom Purucker. Quantifying Amphibian Pesticide Body Burdens for Active Ingredients Versus Formulations Through Dermal Exposure. Presented at 34th Annual Meeting SETAC North America, Nashville, TN, November 17 - 21, 2013.
Impact/Purpose:
Presentation given at SETAC North America 34th in Nashville, TN (Nov 17-21, 2013)
Description:
Widespread pesticide applications throughout agricultural landscapes pose a risk to post-metamorphic amphibians leaving or moving between breeding ponds in terrestrial habitats. Recent studies indicate that the inactive ingredients in pesticide formulations may be equally or more toxic to amphibians than the active ingredient itself. While pesticide active ingredients must be listed on the labeled formulation product by law, disclosure of inactive ingredients is not required. In an effort to indentify the total accumulation of chemicals associated with real world pesticide applications, our study was designed to compare pesticide body burdens (ppm) for 6 active ingredients and associated pesticide formulations through dermal exposure in terrestrial phase amphibians. In spring 2013, 5 southern leopard frog (Rana sphenocephala) egg masses, 5 Fowler’s toad (Bufo fowleri) egg masses and 3 mating pairs of gray treefrogs (Hyla versicolor) were collected from ephemeral pools in University of Georgia’s Whitehall Forest. Amphibians were reared through 30 days post-metamorphosis at the United States Environmental Protection Agency (US EPA) in Athens, GA. All experiments were conducted in 10-gallon glass aquariums lined with Plott series soil in the laboratory at the US EPA. The pesticide active ingredients and associated formulations tested were atrazine and Hi Yield, imidacloprid and Dominion, triadimefon and Triadimefon 125EC, fipronil and Taurus SC, pendimethalin and Prowl, and glyphosate and Roundup. Amphibians were exposed to test compounds indirectly through contact with pesticide contaminated soil for 8 hours. Pesticide body burdens were analyzed using LC-MS after whole body tissue extractions using the QuEChERS method with slight modifications. Preliminary results indicate that formulated pesticide products lead to higher amphibian body burdens as compared to active ingredient only. Given that formulations are sprayed in agricultural fields as opposed to single pesticide active ingredients, this may contribute to increased total chemical exposures and bioaccumulation by amphibians moving throughout contaminated terrestrial habitats. To improve conservation efforts of amphibians worldwide, future research efforts exploring dermal exposure and accumulation of pesticides and their associated carrier compounds by this group of non-target organisms in terrestrial settings is imperative.
