Retrospective Exposure Assessment of Perfluorooctanoic Acid Emissions

Manufacturing facility

Cardno ChemRisk performed a historical exposure reconstruction of perfluoroctanoic acid (PFOA) for residents near a polymer manufacturing facility in West Virginia due to air emissions from 1951 to 2003 to support expert witness testimony as part of a medical monitoring class action.

As part of the exposure reconstruction, a material balance model was developed to estimate the mass of PFOA released to air, water, landfills, and off-site disposal from the mass of the same materials used at the facility from 1951 to 2003. Using these estimated air emissions, for each year from 1951 to 2003, PFOA air concentrations and total deposition to soil were estimated using the ISCST3 air dispersion model.  

PFOA concentrations leaching from soil to groundwater were estimated using the PRZM model using the deposition estimates from the air dispersion modeling, and groundwater concentrations were estimated using the results of the PRZM model. The estimated air, soil, and groundwater concentrations were then used to estimate the Average Daily Doses (ADDs) of PFOA for residents living in five water districts in the vicinity of the facility from 1951 to 2003. The results of this exposure reconstruction were published in the peer-reviewed literature in Paustenbach et al. (2007).  

Exposure reconstruction of perfluoroctanoic acid near a polymer manufacturing facility