Popis: |
The interlaboratory precision of the American Society for Testing Materials (ASTM) early life-stage toxicity test with the sheepshead minnow (Cyprinodon variegatus) was investigated at five contract and two EPA laboratories using endosulfan and pentachlorobenzene. Each laboratory conducted two tests with each chemical. Tests began with 24-hour-old embryos continued through embryonic development, hatching and growth of fish to the juvenile stage and were terminated after 28 days. Effects on survival of embryos, survival of hatched fish and weight of surviving fish were quantified. Rules were developed for judging acceptability of test results and for selecting the upper and lower chronic values. Using these rules, 19 of the 28 tests (68 percent) were judged acceptable. |