Abstract for RR-18

The Consortium Linking Academic and Regulatory Insights on Bisphenol A Toxicity (CLARITY-BPA) is a multi-agency research program developed by the National Toxicology Program (NTP). It was designed to draw upon the strengths of regulatory expertise and research approaches and academic expertise to fill knowledge gaps, enhance quality control, inform chemical risk assessment, and identify new methods or endpoints for regulatory hazard assessments. Bisphenol A (BPA) was chosen as the test chemical because of its widespread low-level human exposure. Participants in the program included researchers from the U.S. Food and Drug Administration (FDA) who conducted the core guideline-compliant studies and 14 university-based researchers who were supported by grants from the National Institute of Environmental Health Sciences (NIEHS). Using a Sprague Dawley rat model, animals were orally dosed with BPA (2.5, 25, 250, 2,500, or 25,000 μg/kg body weight [bw]/day) beginning on gestation day (GD) 6 and continuing through postnatal day (PND) 21 (stop dose) or 2 years (continuous dose). As a positive estrogen control, animals were similarly dosed with ethinyl estradiol ([EE2]; 0.05 or 0.5 μg/kg bw/day) from GD 6 through 2 years of age. This report presents a collation of the reported findings and the peer-reviewed conclusions from the CLARITY-BPA core guideline study (NTP 2018) and the 19 peer-reviewed publications of the investigational research arm. The report is organized into 10 chapters by organ or organ system, including brain and behavior, cardiac, immune, mammary gland, ovary, penile function, prostate gland and urethra, testis and epididymis, metabolism and thyroid hormone, and uterus. This report provides a succinct summary of the experimental procedures, findings, and authors’ interpretations reported in each of the peer-reviewed publications. This report does not attempt to integrate the findings or offer interpretation of reported findings.

CLARITY-BPA Research Program. 2021. NTP research report on the consortium linking academic and regulatory insights on bisphenol A toxicity (CLARITY-BPA): a compendium of published findings. Research Triangle Park, NC: National Toxicology Program. Research Report 18. https://doi.org/10.22427/NTP-RR-18