Teratogenic Assessment of Four Solvents Using the Frog Embryo Teratogenesis Assay - Xenopus (FETAX).

Abstract

Xenopus laevis embryos were exposed for 96 hours to ethanol, dimethyl sulfoxide (DMSO), formamide or glycerol formal. Exposure groups were maintained using a static renewal system where the exposure media were changed at 24-hour intervals. Survival, growth, and developmental abnormalities were also monitored at 24-hour intervals. Using this information the LC50, the EC50 (Abnormalities), the no observable adverse effect levels (NOAEL), and the EC10 (Growth) for each solvent were determined in the FETAX assay. DMSO appeared to be the least toxic or teratogenic solvent examined with an LC50 of 1.92% and an EC50 of 1.57%. Data suggest that formamide was the most toxic solvent with an LC50 of 1.04%. Data trends suggested that ethanol was the most teratogenic solvent tested with an EC50 of 1.03%. The results obtained in the present work for ethanol and DMSO were compared to the FETAX results published in the open literature. These results were in close agreement with results from other laboratories thus providing further evidence supporting the interlaboratory reproducibility of FETAX results.