RIVM PFAS Mixtures Risk Assessment Workshop - PFAS mixtures research and risk assessment

Due to the pervasive detection of multiple PFAS in human and environmental matrices, many health-based agencies are employing or pursuing cumulative assessment and regulatory approaches.  However, the literature is lacking mammalian in vivo studies that test additivity by comparing observed mixture responses to mixture model predictions.  We have conducted three different PFAS mixture studies investigating maternal and neonatal effects from maternal exposure during pregnancy in a rat model.  Experimental data were compared to predictions using established mixtures toxicology approaches and effects were well predicted using dose addition methods.  One of the mixture studies discussed here (PFOA+PFOS mixture) was the result of a request from the Office of Water for technical support of cumulative effects of exposure to multiple PFAS. 

Impact/Purpose

This is a slide deck for an invited presentation at the PFAS Mixtures Risk Assessment Workshop hosted by the Dutch RIVM and WHO.  Due to the pervasive detection of multiple PFAS in human and environmental matrices, many health-based agencies are employing or pursuing cumulative assessment and regulatory approaches.  However, the literature is lacking mammalian in vivo studies that test additivity by comparing observed mixture responses to mixture model predictions.  We have conducted three different PFAS mixture studies investigating maternal and neonatal effects from maternal exposure during pregnancy in a rat model.  Experimental data were compared to predictions using established mixtures toxicology approaches and effects were well predicted using dose addition methods.  One of the mixture studies discussed here (PFOA+PFOS mixture) was the result of a request from the Office of Water for technical support of cumulative effects of exposure to multiple PFAS.  The studies described here are some of the only mammalian in vivo mixture toxicity studies of PFAS that incorporate mixture modeling and analyses to characterize the type of mixture effects and the accuracy of predictions using well-established approaches.  The results directly support the proposed approaches by the Office of Water, as well as state and international health-based agencies that have adopted mixture-based risk assessment and regulatory approaches for exposure to multiple PFAS.

Citation

Conley, J. RIVM PFAS Mixtures Risk Assessment Workshop - PFAS mixtures research and risk assessment. Workshop Mixture Risk Assessment Approaches to Evaluate Oral Exposure to PFAS, Virtual, Virtual, NETHERLANDS, October 23 - 24, 2024.