UC Irvine

PFAS and air pollution are two groups of modifiable risk factors in the environment. According to the National Health and Nutrition Examination Survey, PFAS are ubiquitous in the serum of the general US population. Contaminated seafood and drinking water, packaged fast food, stain-resistant or water-repellant consumer products, dust, and air are the major exposure routes to humans. In addition, ambient air pollution remains the greatest environmental risk factor and is associated with 100,000-200,000 deaths annually in the US, although the air quality in the US has dramatically improved over the past few decades compared to its historical levels and other countries in the world. Infants, pregnant women, and elderly people are three typical populations that are especially susceptible to these environmental pollutants. In Chapter 2, we examined the associations between serum PFAS concentrations and type of residential flooring among the general US population aged 12 years and older using the 2005-2006 NHANES survey data. We concluded that low pile carpeting was associated with increased serum concentrations of PFHxS and MeFOSAA in the general US population. In Chapters 3 and 4, we conducted two nationwide studies investigating the impacts of PFAS detected in drinking water on birthweight and HDP status, respectively. We used county-level aggregated PFAS data from EPA UCMR3 and county-level multiple-stratified birth/pregnancy data from CDC WONDER. We concluded that the PFAS mixture found in drinking water may contribute to low birthweight and hypertensive disorder of pregnancy in the US. In Chapters 5 and 6, we further conducted two subgroup analyses using data from the C8 and IHS projects, respectively, focusing on two population subgroups with significantly higher environmental exposure to PFOA and O3 in the US due to local industries. Our studies suggest PFOA is moderately associated with preeclampsia in the C8 project and O3 is associated with a higher risk of dementia in American Indians. Future efforts to reduce exposure to PFAS and air pollution might help lower risks of low birthweight, hypertensive disorders of pregnancy/preeclampsia, and dementia in the US.