PARENT SESSION
PS6 - Contaminant Effects on Amphibians & Reptiles
Sunday, 17 November 2002
8:00 AM to 6:30 PM
Exhibit Hall
(P084) Developmental Toxicity of Copper Sulfate and Atrazine using FETAX.
Hamilton, Misty*,1, Smith, David1,2, 1 Morehead State University, Morehead, Kentucky, United States2 Institute for Regional Analysis and Public Policy, Morehead, Kentucky, United States
ABSTRACT- Much of the recent research into the cause of amphibian declines and deformities has placed emphasis on pesticides. Copper sulfate and atrazine are among the most commonly used pesticides in the United States. Copper sulfate (CuSO4) is a highly toxic General Use Pesticide used as a fungicide, algacide, and herbicide on many crops. Atrazine (2-chloro-4-ethlyamine-6-isopropylamino-S-triazine) is a Restricted Use Pesticide used to control weeds in many croplands and fallow lands. Lethal concentrations have been determined for both of these pesticides, but teratogenic effects have not been quantified. This study analyzed the teratogenicity of copper sulfate and atrazine using the Frog Embryo Teratogenesis Assay Xenopus (FETAX). One copper sulfate test resulted in an EC50 of 151 and an LC50 of 845 
g/L. The NOAEC and LOAEC for mortality were 250 g/L and 1000 g/L, and for deformity were 0.24 g/L and 0.98 g/L. Two copper sulfate tests using eggs from the same egg mass found EC50 values of 555 g/L and 314 g/L, and LC50 values of 677 g/L and 600 g/L. For both tests, the NOAEC and LOAEC were respectively 300 g/L and 600 g/L for mortality and 150 g/L and 300 g/L for deformity. Analysis of occurrence of selected deformities with increasing copper concentration found that gut malformations and edema were the most common, occurring at almost all concentrations. At 1000 g/L all surviving tadpoles showed stunted growth, head and gut deformities, and axial malformations. Two atrazine tests using eggs from the same egg mass resulted in EC50 values of 11.4 mg/L and 10.2 mg/L, and LC50 values of 204.8 mg/L and 220.8 mg/L. The NOAEC and LOAEC for mortality were respectively 50 mg/L and 100 mg/L for one test, and 100 mg/L and 200 mg/L for the second test. The NOAEC and LOAEC for deformity for both tests were 6.25 and 12.5 mg/L. Analysis of selected deformities found that cardiac edema and axial malformations were the most common, occurring at almost all concentrations. Gut malformations, abdominal edema, and optic edema appeared at 25 mg/L. All deformities increased with increasing atrazine concentration, with all surviving tadpoles at 200 mg/L having all deformities. Additional testing will use the FETAX experimental design to evaluate the teratogenicity of copper sulfate and atrazine to Rana catesbeiana.
Key words: FETAX, Xenopus laevis, copper sulfate, atrazine