PM01 Amphibian Research and Monitoring
Exhibit Hall
8:00 AM - Monday, 10 November 2003
(PM015) Effects of water and sediments near the Anniston (AL) Monsanto plant on Xenopus embryos by FETAX and inmmunoblotting.
Sauterer, Roger1, Millwood, Mary1, Sikes, Joseph 1, Rayburn, James1, 1 Jacksonville State University, Jacksonville, AL 36265, USA
ABSTRACT- The Anniston (AL) Monsanto plant heavily contaminated local soils and watersheds with PCB-laden runoff from on-site landfills. In order to assess potential toxic effects of this PCB contamination on a model amphibian species under laboratory conditions, we analysed water and aqueous sediment extracts from three sites on Snow and Choccolocco creeks on developing Xenopus embryos by the FETAX assay and are attempting to quantitate CYP 1A levels in embryos by immunoblotting. The FETAX assay shows inhibition of embryonic growth with the most pronounced effects using water and sediment extracts from the Snow Creek site 1 km from the plant. Less pronounced growth inhibition was seen using water and sediment extracts from Choccolocco Creek sites farther from the Monsanto plant. Effects were stonger using sample waters rather than with sediment extracts in all three sites tested. None of the sites showed increases in embryonic mortality or malformations. We are investigating CYP 1A levels in control embryos and embryos exposed to test extracts by immunoblotting with a variety of antibodies against CYP 1A. Currently tested antibodies show weak cross-reaction but high background using whole 4-day embryo extracts and lesser background using crude microsome preparations from the embryos. Antibodies showing strong signal and low background will be used to assess whether exposure of embryos to contaminated waters and sediment extracts induce CYP 1A levels. We tentatively conclude that uncharacterized agents in the test waters and sediments cause growth inhibition and that these agents may be associated with the Monsanto plant.
Key words: Xenopus, FETAX, PCBs, Anniston, AL Monsanto Site