THE EVALUATION OF CONTROL PERFORMANCE IN THE AMPHIBIAN METAMORPHOSIS ASSAY (OPPTS 890.1100) AND IN THE FISH SHORT-TERM REPRODUCTION ASSAY (OPPTS 890.1350) WITH EMPHASIS ON WEIGHT OF THE EVIDENCE EVALUATION OF THE ENDPOINTS FOR POTENTIAL INTERACTION WITH THE ANDROGEN, ESTROGEN AND THYROID HORMONE SYSTEMS

摘要

The United States Environmental Protection Agency (USEPA) has begun to execute a new paradigm with the Endocrine Disruptor Screening Program (EDSP). The goal is to screen chemicals for potential endocrine or thyroid activity. Screening is being conducted using 11 Tier 1 assays. Two of those assays are the Amphibian Metamorphosis Assay (AMA) and the Fish Short-Term Reproduction Assay (FSTRA). Although the OPPTS 890 assay guidelines are very specific, it is not a trivial matter to meet the acceptance and performance criteria. This presentation will evaluate control performance data from at least 12 assays conducted over the past 10 months and compare this performance against recommended acceptance and performance criteria presented in their respective OPPTS 890 and OECD guidelines. In addition, this presentation will propose weight of evidence (WoE) designation of critical endpoints like developmental stage and thyroid histopathology from the AMA and fecundity, fertility, gonad histopathology, gonadal somatic index, blood plasma vitellogenin and male tubercle score from the FSTRA. The WoE designations will also take into consideration endpoint results from the other 9 Tier 1 EDPS assays.