Retrospective Exposure Assessment for Perfluorooctanoic Acid (PFOA)
- Challenge: Cardno ChemRisk was asked by a fluoropolymer manufacturing facility to help resolve concerns that residents were allegedly exposed to perfluorooctanoic acid (PFOA) from manufacturing operations. This project was conducted as part of litigation by plaintiffs whose suit requested medical monitoring of those involved in the class action.
- Approach: Cardno ChemRisk conducted a retrospective exposure assessment of PFOA for approximately 50,000 residents who lived near the facility. Cardno ChemRisk calculated PFOA emissions from the facility over 50 years using historical purchasing records and process engineering data. The emissions data were used as input for linked air dispersion, soil, surface water and groundwater transport models to estimate PFOA exposures.
- Findings: Cardno ChemRisk scientists quantified PFOA in various environmental media. The primary exposure pathway of PFOA was determined to be ingestion of drinking water. Results were published in the peer-reviewed scientific literature.
- Value: This was one of the first studies to characterize the movement of chemicals with PFOA-like properties in multiple environmental media. The client was able to develop an appropriate risk management strategy and reach a settlement with the plaintiffs.
- A Methodology for Estimating Human Exposure to Perfluorooctanoic Acid (PFOA): A Retrospective Exposure Assessment of a Community (1951-2003)