Environmental Exposure to Per- and Polyfluoroalkyl Substances and Cancer Risk: A Scoping Review
Creators: name: Wilson, Robin
name: Jones, Resa
name: Holtz, Samantha
name: Stranick, Allison
name: Wood, Susan
name: Feiler, Marina
Publisher: name: Open Science Framework
Year: 2022
Subjects: subject: Environmental Public Health
subject: Neoplasms
subject: Diseases
subject: Public Health
subject: Medicine and Health Sciences
subject: Epidemiology

description: Per- and polyfluoroalkyl substances (PFAS) are environmentally persistent heat- and water-resistant compounds, some of which are known to have become environmentally ubiquitous due to use in a wide variety of products since World War II. These compounds include, but are not limited to, stain resistant carpets, stick-resistant cookware, leather/textile coating, paper, upholstery, metal plating, or as polymerization aids in the manufacture of fluoropolymers and aqueous fire-fighting foams (AFFF) used by the United States (US) military, petrochemical, and aviation industries (Paul, 2009; Glüge, 2020). In addition to wide use, PFAS have been shown to bioaccumulate within species relative to the surrounding environment (De Silva, 2021; Burkhard, 2021; Death, 2021). In the general US population, the major exposure pathways are dietary ingestion due to contamination of the food chain (e.g., fish intake) and ingestion of PFAS-contaminated public and private drinking water sources (De Silva, 2021). Other exposure pathways in the general population include diet (e.g., food prepared/wrapped in PFAS-containing containers), recreational swimming in PFAS impacted water, and inhalation of household dusts (Falandysz, 2006; Ghisi, 2019; Ng, 2015; Schwichtenberg, 2020; Trudel, 2008). Several susceptibility factors to PFAS exposure and body burden exist including biologic sex, dietary intake, genetic, and socioeconomic factors. Mechanistic studies of perfluorooctanoic acid (PFOA) and perfluorooctanesulfonic acid (PFOS) have consistently identified sex differences in serum half-life and tissue concentrations in liver and kidney (Kim, 2016; Huang, 2019). Biomonitoring studies of humans report higher blood concentrations in males (Nair et al., 2021) and male fetuses (Björvang, 2021). Higher adult male concentrations compared with adult females have been hypothesized to be due to decrease in PFAS body burden among females via menstruation, pregnancy and breastfeeding (Pirard, 2020). Higher male fetal tissue concentrations have been hypothesized to be caused by higher transfer of maternal blood contaminants to male fetuses due to lower placental vascular resistance in male offspring pregnancies, compared to pregnancies with female fetuses (Widnes, 2017). In the US, Norway and Belgium a systematic review identified higher socioeconomic status associated with higher PFAS serum concentrations (PFHxS, PFNA, PFOA and PFOS) in a recent systematic review (Buekers, 2018). More recently, serum concentrations of PFOS and perfluorononanoic acid (PFNA) are reported to be significantly higher among African (black) Americans, compared with Caucasian (white) Americans in two separate surveys in the United States (Lin, 2021). Dietary intake of packaged foods and fish (Seshasayee, 2021) are associated with higher PFAS concentrations (i.e., 2-(N-Methyl-perfluorooctane sulfonamido) acetic acid (MeFOSAA) MeFOSAA and PFOS) while dietary intake of fiber may prevent re-absorption of PFAS in the biliary cycle, leading to reduced body burdens (Dzierlenga, 2020). Finally, differences in genetic variation have been associated with differing rates of placental transfer of PFAS (Gundacker, 2021), suggesting that cancer may also differ by genetic susceptibility factors. Currently, few scientific reviews of PFAS and cancer risk have been published (Steenland, 2020; Fenton, 2021; Petersen, 2021). No scoping systematic review to date has focused on susceptibility factors, including sex, socioeconomic factors, and genetic variants. In addition, to our knowledge, only one systematic review has included a risk of bias assessment, but this was only with respect to studies of testicular cancer (Petersen, 2021).