PFCs are not found naturally, are chemically stable, and persistent in the environment.
Because of their widespread use, most people in the United States have some PFCs in their body. Data from human studies suggest that some PFCs can take years to be cleared from the body (Bartell et al., 2010; Seals et al., 2010). Once the PFCs are in a person’s body, it takes from 2 to 9 years before PFC levels go down by half, even if no more is taken in or produced. This half-‐life results in continued exposure that could increase body burdens to levels that would result in adverse outcomes (ATSDR 2009; Olsen, 2007).
Potential pathways, which may lead to widespread exposure, include ingestion of food and water, use of commercial products or inhalation from long-‐range air transport of PFC-‐containing particulate matter (ATSDR 2009). One primary source of exposure is drinking water (Rumsby et al 2009). Other common sources of exposure include (Fromme et al., 2009):
- Food containers (i.e. pizza boxes, fast food wrappers, popcorn bags)
- Furniture, including mattresses
- Carpets treated for stain resistance
- Water-‐proof clothing and accessories
- Non-‐stick cookware (e.g., Teflon)
- Firefighting foams
- Windshield washer fluids
- Aerospace, automotive, electronic, and construction projects
- Environmental residue (i.e. air, dust, groundwater, soil)
- PFOAs are persistent, bio-‐accumulative, and known to be contaminants in waterways and can bio-‐accumulate within fish; fish consumption represents a common exposure route (Egeghy and Lorber, 2011; Trudel et al., 2008). While a federal screening level or toxicity value for the consumption of fish has not yet been established, the Dutch National Institute for Public Health and the Environment has calculated a maximum permissible concentration for PFOS of 0.65 nanograms per liter (ng/L) for fresh water (based on consumption of fish by humans as the most critical route) (Moermond, 2010). Michigan has developed provisional fish consumption screening value ranges for PFOS – See “Michigan Fish Consumption Advisory Program” Guidance Document, available under “Reports and Science” at michigan.gov/eatsafefish.
- PFCs can migrate from food packaging to food (with concentrations occurring in high-‐fat foods, such as microwave popcorn and fast food).
- Traditional drinking water treatment techniques do not remove long chained (LC)-‐PFCs, so contamination of ground water or surface water, or both, can lead to contamination of drinking water (ATSDR, 2009).
- Because of the high number of household and consumer products that contain PFCs (e.g., carpet, textiles) dust ingestion is another route of exposure to consider for young children, who spend a high percentage of time on the floor and have high hand-‐to-‐mouth contac (Haug et al., 2011; Shoeib et al., 2011).
- PFOS and PFOA are unlikely to be taken up by plant roots via contaminated However, in one study PFCs were taken up into plants (grasses and barley) grown on contaminated soil (e.g., from application of contaminated sewage sludge). Plant uptake of PFCs decreased with chain length with the shortest PFC in study (C6) having the greatest uptake (Yoo et al., 2011).
- People can be exposed from dermal contact with carpets or clothing, although this is not considered a primary route of