Composition of per- and polyfluoroalkyl substances (PFAS) in house dust from United States homes
On this page:
House dust can be an aggregate of harmful chemicals present in residential environments and an important exposure route for per- and polyfluoroalkyl substances (PFAS). The composition of PFAS chemicals in house dust can be a function of the home’s proximity to point sources or different household materials (i.e., consumer products, furnishings, carpeting, cookware, clothing, and cleaning products) in the home. The U.S. Department of Housing and Urban Development (HUD) conducted the first survey of residential hazards called the American Healthy Homes Survey (AHHS) in 2005, which was followed by a second survey (AHHS II) in 2017. The U.S. Environmental Protection Agency (EPA) collaborated with HUD on both of these efforts and received subsequent OMB approval to analyze PFAS in house dust collected during the AHHS II study. While not considered nationally representative, the AHHS II house dust samples were collected in many regions throughout the contiguous U.S. and Hawaii. We analyzed ~250 house dust samples from homes in 37 states for 16 PFAS chemicals (PFOA, PFOS, PFNA, PFNS, PFHxS, PFHxA, PFBS, PFBA, PFDA, PFDoA, PFDS, PFHpA, PFHpS, PFPeA, PFPeS, PFUnDA). All targeted chemicals were detected in the house dust samples, with detection rates ranging from 9% for PFNS to 97% for PFOA. Eight chemicals (PFOA, PFNA, PFOS, PFHxS, PFDA, PFUnDA, PFDoA, and PFHpA) were measured above the limit of detection in at least 60% of house dust samples. Overall, the highest median concentrations observed in house dust were PFOS (9.07 ng/g) and PFOA (8.57 ng/g). The highest maximum concentrations measured were PFDA (4275.8 ng/g) and PFOA (4067.8 ng/g). Questionnaire and geographic information collected alongside the house dust samples will be analyzed to investigate variability in the composition of PFAS chemicals in house dust related to demographics, behaviors and activities, housing characteristics, and proximity to point sources.