PFAS Exposure and Health Effects in El Paso County; Colorado

Project Summary/AbstractThe overall goal of this research is to quantify the cross-sectional associations between measured andmodeled perfluoroalkyl and polyfluoroalkyl substances (PFAS) in highly exposed adults and children andselected health outcomes, including lipids, kidney function, liver function, thyroid hormones and sex hormones,glucose and insulin parameters, markers of immune function, and neurobehavioral outcomes in children. Wewill enroll 1,000 adults and 400 children from a community in El Paso County, Colorado who experienced highlevels of PFAS contamination of their municipal drinking water and private wells resulting from the use ofaqueous film-forming foams (AFFF) for firefighting activities at a nearly US Air Force Base. Exposure to PFASwill be assessed via measured serum concentrations and through a detailed model to reconstruct historicalPFAS concentrations in groundwater and drinking water in El Paso County. Combining this information withindividual residential histories, we will be able to estimate cumulative lifetime exposure to AFFF-related PFASin El Paso County for each study participant. Our research team is well qualified to achieve this goal due to ourcomplementary expertise in exposure science (Adgate), environmental epidemiology (Starling), PFASchemistry and drinking water exposure (Higgins, Vestergren), groundwater modeling (Singha, McCray),neurobehavioral testing (Wilkening), cancer epidemiology (Cockburn), statistical methods for the analysis ofobservational data (Glueck), and community outreach and education (Richardson, Celico). We have conducteda pilot study in El Paso County that demonstrates the feasibility of recruiting participants to complete studyprocedures similar to those in the ATSDR protocol. The preliminary results of our pilot study show: (1) a uniqueAFFF-related exposure profile with median concentrations of perfluorohexane sulfonate (PFHxS) more thanten times the median of the general US population, and (2) prominent differences in AFFF-related PFASexposure by geographic area with an apparent north-south gradient in serum concentrations within El PasoCounty. In addition to the common core protocol, we propose two investigator-initiated aims: (1) a highlyinnovative examination of the association between PFAS and biomarkers linked to testicular and thyroidcancer risk (both previously identified in human and animal studies as potentially related to PFAS exposure),and (2) the application of novel statistical methods to estimate the combined effect of exposure to the complexmixture of PFAS found in AFFF-contaminated drinking water, and to separate the effects of individual PFASfrom the correlated mixture. This research fills an important knowledge gap because populations in numerousUS states have been exposed to AFFF-derived PFAS via contaminated drinking water. The completion ofthese aims will provide essential information for communities, researchers, and policymakers seeking tounderstand the health risks associated with this emerging PFAS exposure profile.