Sources of Exposure to PFAS

 

How can people be exposed to PFAS?

PFAS are man-made, so there are no natural sources in the environment. However, PFAS can be found near areas where they are manufactured or where products containing PFAS are often used. PFAS can travel long distances, move through soil, seep into groundwater, or be carried through air. 

Because they are stable chemicals and move so easily in the environment, PFAS have been found in soil, sediment, and water samples far away from where they were made or used. And since PFAS have been so widely used and don’t break down, they have been found not only in the environment, but also in the blood of humans and animals worldwide. They have even been found in the Arctic and Antarctic.

Potential sources of PFAS in the environment may include industrial sources, areas where PFAS are used frequently, and consumer products. Listed below are places where they can be found.

• Public water systems and drinking water wells, soil, and outdoor air near industrial sources or areas with frequent PFAS use
  Many PFAS do not evaporate easily, so they usually are not found in large amounts in the air. But higher amounts have been measured in the air around factories that make PFAS or products containing PFAS. So exposures for people who live near PFAS factories may be higher than for people who don’t.
  
• Indoor air in spaces that contain carpets, textiles and other consumer products treated with PFAS to resist stains
  Children who lie, crawl, or play on carpets treated with PFAS may have higher exposure.
  
• Surface water (lakes, ponds, etc.) and run-off from areas where aqueous (water-based) film-forming firefighting foam (AFFF) is often used, such as military or civilian airfields)
  
• Locally caught fish from contaminated bodies of water
  Studies have found that PFOS in particular can build up (bioaccumulate) in fish.  Fish that are higher up the food chain can accumulate high concentrations of the chemicals.
  
• Food items sold in the marketplace
  In general, the concentration of PFAS in food items is low. However, many studies have suggested that outside of job-related exposure, food contaminated with low levels of PFAS is the most likely source of exposure for the general population in industrialized nations.
  
• Breastmilk
  PFAS can move from a mother’s blood into her breast milk. However, concentrations of PFAS in the breast milk are much lower than in the mother’s blood.
  

Consumer products are a potential source of PFAS, although research has suggested that exposure from consumer products is usually low, especially when compared to exposures to contaminated drinking water. These consumer products include

• Some grease-resistant paper, fast food containers/wrappers, microwave popcorn bags, pizza boxes, and candy wrappers
• Nonstick cookware such as Teflon® coated pots/pans
• Stain resistant coatings such as Scotchguard® used on carpets, upholstery, and other fabrics
• Water resistant clothing such as Gore-Tex®
• Cleaning products
• Personal care products (shampoo, dental floss) and cosmetics (nail polish, eye makeup)
• Paints, varnishes, and sealants

Workers involved in making or processing PFAS are more likely to be exposed than the general population. Workers may be exposed to PFAS by inhaling them, getting them on their skin, and swallowing them, but inhaling them in the most likely route for exposure.

Recent efforts to stop or reduce producing and using PFOS and PFOA in consumer products appear to have lowered exposure to the general U.S. population. CDC’s National Health and Nutrition Examination Survey (NHANES) has shown that blood concentration of PFOS, in particular and other PFAS have dropped over time. (Figure 2).