Socioeconomic Disparities and Risk of Papillary Thyroid Cancer Associated with Environmental Exposure to Per- and Polyfluoroalkyl Substances (PFAS) in Florida

The existing literature suggests that exposure to Per- and Polyfluoroalkyl Substances (PFAS) can increase Papillary Thyroid Cancer (PTC) risk by interfering with thyroid hormone signaling, leading to hormonal imbalances that promote carcinogenesis. In addition, significant disparities exist in environmental exposure. However, ecological evidence of these associations has not been established within a statewide database of cancer outcomes. Therefore, this study investigated the relationship between socioeconomic conditions, environmental PFAS exposure, and PTC incidence in Florida using the state's cancer registry. Data on facilities potentially releasing PFAS and ZIP codes with known PFAS drinking water contamination were retrieved from the EPA's PFAS Analytic Tool. Proximity to PFAS sites and age-adjusted incidence by patient race/ethnicity were calculated by census tract. Lower socioeconomic status was associated with greater exposure to environmental PFAS. Census tracts with closer proximity to PFAS sites were more likely to have public water systems with PFAS contamination. Lastly, residential proximity to PFAS sites was positively associated with age-adjusted PTC incidence in Non-Hispanic Whites and Hispanics. These results demonstrate disparities in environmental exposure and suggest that exposure to PFAS may be an important factor for PTC risk at the population level and should be considered in the development of public health policies.