Exposure pathways and mental health impact of PFAS-contaminated biosolids

PROJECT ABSTRACT Per- and polyfluoroalkyl substances (PFAS) are persistent “forever chemicals” that make paper and other products stain resistant, but also contaminate water and food and are detectable in almost every individual in the US. An understudied exposure source is farmland throughout the rural US where PFAS-contaminated

biosolids are applied as fertilizer. Incomplete information about non-water exposure pathways leaves affected communities, many of whom are dependent on local agriculture and game for work and food, uncertain how to minimize exposure. PFAS-contaminated biosolids threaten the livelihoods and food sources of these agrarian

communities, as plant and wildlife exposure to PFAS from biosolids makes selling and consuming local produce, animal products, or wild fish and game no longer safe. Maine has the unique capability to investigate these issues because of 2021 state legislation that mandated PFAS testing on land with prior or ongoing

application of biosolids. One sentinel site, the town of Fairfield, was found to have PFAS up to the 1000’s mg/kg in soil and 30,000’s ng/L in drinking water from private wells—far above local and national health advisories (EPA’s drinking water advisory is 0.004 ng/L for PFOA). As of now, there are enough impacted

individuals across central Maine [319 wells with PFAS above the Maine health advisory (sum of 6 legacy PFAS ≥ 20 ng/L)] to establish a cohort to guide other communities affected by biosolids across the US. In this study, our objective is to recruit 300 adults at risk of exposure to PFAS from biosolids to (1) quantify PFAS

concentrations in serum, (2) evaluate water and non-water exposure pathways, and (3) characterize associations of PFAS with anxiety and perceptions of health risk and stigmatization. The time-sensitive R21 mechanism will allow us to obtain an immediate assessment of serum PFAS levels, which is critical because

some affected individuals learned of the contamination and had a water filter installed up to 2-years ago. PFAS have long half-lives (3-8-years depending on the compound), and serum measures up to 2-years post-clean water will be consistent with other community contamination cohorts. To minimize recall bias, it is also

imperative before more time elapses to assess water intake, other potential exposure pathways, and anxiety and perceptions of health risk/stigmatization before and after knowledge of the contamination. Our interdisciplinary team has expertise in environmental epidemiology, clinical care of patients with PFAS

exposure, and social psychology. We will partner with the community through a community advisory board, context-rich report back of individual results, and presentation of aggregated study results at town hall meetings. We will be the first to our knowledge to establish a cohort with PFAS exposure from biosolids, and

our results will help to generate exposure mitigation advice and interventions to build resilience among individuals living in communities impacted by PFAS-contaminated biosolids.