Assessing association between PFAS exposure, social determinants of health, and risk outcomes in adolescents and adults in the United States

Abstract

Per- and poly-fluoroalkyl substances (PFAS), aka forever chemicals, are known for their eco-persistence, resistance to degradation, and longer half-life. Emerging studies have linked PFAS exposure to various adverse health effects, including cancer, liver damage, immune system disruption, reproductive issues, and endocrine disruption. By evaluating PFAS blood serum concentrations (n=4,444) using complex logistic regression and the USEPA deterministic risk assessment framework, this research aimed at elucidating the role of social determinants on PFAS exposure and estimate potential health risks among adolescents and adults from drinking contaminated water. Males showed higher odds of detecting pefluorodecanoic acid (PFDA), perfluorohexane sulfonic acid (PFHxS), perfluorononanoic acid (PFNA), and branched PFOA than females. PFDA and 2-(N-Methyl-perfluorooctane sulfonamido) acetic acid (Me-PFOSA-AcOH) and Perfluoroundecanoic acid (PFUA) detection in blood was significantly associated with adolescents (12-15 and 16-20 years) and adults (21-40 and 41–60 years). Adults aged 21-40 years had 33% lower odds of detecting PFNA in blood compared to adults aged 61 years and older. Detection of PFAS in blood was chemical-specific for Race/Ethnicity. Non-Hispanic Asians had significantly higher odds of blood PFDA (p=.007, OR=2.39) and PFUA (p<.001, OR=2.482) compared to Other Race; whereas Mexican Americans, Other Hispanics, and Non-Hispanic Asians had 32%, 44%, and 46% lower odds of blood Me-PFOSA-AcOH detection compared to Mixed or Other Race, respectively. Individuals with higher income-to-poverty ratios had significantly higher odds of blood Me-PFOSA-AcOH (p<.001, OR=1.705). Furthermore, estimated non-cancer risks based on drinking water PFAS concentrations were highest for PFHxS, PFNA, PFUA and PFOA across various age groups and exposure scenarios. Cancer risk for PFOA was highest in the high exposure scenario [12 to 15 age group: 4.0 x 10-6, 16 to 20 age group: 3.0 x 10-6, 21 to 40 age group: 3.0 x 10-6, 41 to 60 age group: 3.0 x 10-6, 61 years and older: 2.0 x 10-6] with younger individuals being more at risk than older adults. These findings support the hypotheses that social determinants (gender, age, race/ethnicity, and income) are associated with higher PFAS exposure and that adolescents may face a higher risk of adverse non-cancer health effects from PFAS in drinking water compared to adults. The findings of this study stress the importance of continued monitoring, additional regulatory action to safeguard public health, targeted public health interventions to limit exposure (particularly in younger populations), and call for further research to identify additional sources of exposure and reassess risk estimates.