Advancing read-across practice and applications for the evaluation of data-poor environmental chemicals within the U.S. EPA PPRTV program.
On this page:
The U.S. Environmental Protection Agency derives Provisional Peer-Reviewed Toxicity Values (PPRTVs) that support the Superfund program in chemical-specific clean-up efforts. However, many chemicals found at contaminated sites lack epidemiological or animal toxicity data necessary for traditional hazard identification and dose-response analysis, preventing regulatory agencies from establishing health reference values that inform clean-up levels. To overcome this challenge, the PPRTV program has developed and implemented a read-across approach for screening-level quantitative assessment of target chemicals with limited in vivo toxicity information. The methodology relies on a weight of evidence approach for the identification and evaluation of suitable analogues based on structural, toxicokinetics and toxicodynamic properties. Case study examples will be presented, outlining lessons learned and future outlooks for advancing and expanding read-acros applications. Important considerations for problem formulation, target chemical analysis, analogue identification and evaluation and incorporation of data derived from new approach methods (NAM) and tools will also be discussed to increase the transparency and scientific rigor of read-across evaluations. This work emphasizes the integration and translation of computational and expert-driven techniques in chemical assessment with the potential to inform a broad landscape of regulatory decision-making. The views expressed in this abstract are those of the authors and do not necessarily reflect the views and policies of the U.S. EPA.