Research Highlights

Measuring and Tracking PFC-Related Compounds in Indoor Environments

Podcasts

Listen to or download the podcast to learn more about how NRMRL research helps to support the protection of human health and the environment.

 

PFCs (perfluorinated chemicals) make possible hundreds of popular nonstick and water-repellant commercial products. However, by their very nature, PFCs do not break down easily; instead, they accumulate in the environment and have been found in water, air, soil, and in human and animal blood world-wide. While researchers recognize the pervasive nature of PFCs, they do not agree on their sources, degree of health risk, or routes of exposure. Indoor environmental researchers at EPA’s National Risk Management Research Laboratory are studying one class of these human-made compounds called perfluorocarboxylic acids (PFCAs) to compare them in terms of source concentrations in a variety of commercial products. A key goal is to develop baseline data for long-term release monitoring and potential policy making.

Background

Fabric samples used in PFCA source-concentration measurements.

PFCs were first manufactured in the mid-20th century and were quickly adopted by consumers for their ability to repel stains and water. PFCs have many uses—as industrial surfactants and emulsifiers, and in the manufacture of stain-repellent carpeting, water-resistant fabrics, food packaging, cleaning products, fire-fighting foam and hundreds of other applications. Unfortunately, the very qualities that make PFCs so useful also make them highly persistent in the environment. Over the past several decades, they have been detected in polar bears in the arctic, whales in the North Sea and in the blood of other animals and birds around the globe. PFCs have also been detected in human blood. By the turn of the century, studies began showing evidence of widespread environmental contamination from PFCs. One class of PFCs in particular, PFOS (perfluorooctanesulfonic acid) and PFOS-related chemicals, presented concerns. Because of their toxicity, bioaccumulation, persistence, and long half-life in humans, these chemicals were phased out in the United States in 2002.

PFCA Research

Concern about the potential health risks of another class of PFCs, perfluorocarboxylic acids (PFCAs), prompted intensive research on the sources, transport, transformation and distribution of these chemicals. The presence of indoor sources was first suggested by early research that showed elevated levels of PFCAs in house dust. To expand understanding of this route of exposure, NRMRL air quality researchers undertook a study of 116 selected consumer products (“articles of commerce”) for their potential role in airborne PFCA exposure.

Earlier studies of articles of commerce in households had focused on a single compound—PFOA (perfluorooctanoic acid)—but research on other PFCAs in a broad variety of products was scarce. The EPA research goal was to identify the major PFCA sources in indoor (non-occupational) environments by determining the content of these chemicals in a broad variety of products and ranking them in terms of source concentrations. The study analyzed 116 products purchased from retail outlets between March 2007 and May 2008 to determine the extractable PFCA content, using a newly developed extraction/analytical method. PFOA content concentrations covered a wide range from nondetectable to as high as 6750 ng/g.

Results suggested that, based on the 13 article categories studied, pretreated carpeting and commercial carpet-care liquids are likely the most significant PFCA sources in typical American homes. For homes without carpeting, floor waxes and stone/tile/wood sealants that contain fluorotelomer products are important sources of PFCAs. Household carpet/fabric-care liquids and foams are also potentially important sources. Data from this report may help explain why PFCAs are frequently detected in house dust.

While researchers do not understand all sources and pathways of exposure nor the exact mechanisms by which PFCAs are transferred from sources to household dust, existing data strongly suggest that articles of commerce may contribute to indoor human exposure either directly through dermal contact and hand-to-mouth activities or indirectly through inhalation of dust. Researchers noted that the market for PFCA-containing products has been in a transition period, and limited data suggest that the PFCA content in household articles of commerce is showing a downward trend. Definitive confirmation of such a trend will require long-term monitoring.

In 2006, EPA initiated the 2010/15 PFOA Stewardship Program in which eight major companies in the industry committed voluntarily to a 95 percent reduction in facility emissions and product content of PFOA (and related chemicals) on a global basis by 2010. They further committed to work toward elimination of these chemicals by 2015. To measure the degree of success of this program, NRMRL researchers plan to continue to monitor the market trends and to study measures for reducing potential exposure to PFCAs in indoor environments. Further information on this research is available on the Perfluorocarboxylic Acid Content in 116 Articles of Commerce Abstract page.

Contact

Jane Ice, NRMRL Office of Public Affairs (513) 569-7311

Hot Off the Presses—NRMRL Publications

Journal Articles

Ganguli, A.C., D.M. Engle, P.M. Mayer, and E.C. Hellgren. (2008) “Plant Community Diversity and Composition Provide Little Resistance to Juniperus Encroachment.” Canadian Journal of Botany. NRC Research Press, Ottawa, Canada, 86(12):1416–1426.

Lee, J., T.C. Keener, and Y.J. Yang. (2009) “Potential Flue Gas Impurities in Carbon Dioxide Streams Separated from Coal-fired Power Plants.” Journal of the Air & Waste Management Association. Air & Waste Management Association, Pittsburgh, PA, 59(6):725–732.

Lytle, D.A. and M.R. Schock. (2009) “The Inhibitation of Pb(IV) Oxide Formation in Chlorinated Water by Orthophosphate.” Crystal Growth and Design. American Chemical Society, Washington, DC, 43(17):6624–6631.

Stander, E.K. and J.G. Ehrenfeld. (2009) “Rapid assessment of urban wetlands: Do hydrogeomorpic classification and reference criteria work?” Environmental Management. Springer-Verlag, New York, NY, 43(4):725–742.

Conference Proceedings

Rowe, A.A., M. Borst, T.P. O'Connor, and E.K. Stander. (2009) “Pervious Pavement System Evaluation.” In Proceedings, World Environmental & Water Resources Congress 2009, Kansas City, MO, May 17–21, 2009. American Society of Civil Engineers (ASCE), Reston, VA, 1–8.

EPA Published Reports

U.S. EPA. (2009) Arcadis G&M. “Quantifying Uncontrolled Air Emissions from Two Florida Landfills.” (EPA/600/R-09/046).

U.S. EPA. (2009) Chen, A.S., J.P. Lipps, S. McCall, and L. Wang. “Arsenic Removal from Drinking Water by Adsorptive Media U.S. EPA Demonstration Project at Richmond Elementary School in Susanville, CA. Final Performance Evaluation Report.” (EPA/600/R-09/067).

U.S. EPA. (2009) Chen, A.S., L. Wang, and W.E. Condit. “Arsenic Removal from Drinking Water by Iron Removal U.S. EPA Demonstration Project at Vintage on the Ponds in Delavan, WI. Final Performance Evaluation Report.” (EPA/600/R-09/066).

U.S. EPA. (2009) RTI International. Environmental Technology Verification—“Baghouse Filtration Products: GE Energy QG061 Filtration Media.” (Tested September 2008). (EPA/600/R-09/092).

Book Chapter

Patterson, C.L. and R. Haught. (2009) “Regulatory Considerations to Ensure Clean and Safe Drinking Water.” In Chapter 7, Handbook of Water Purity and Quality. IWA Publishing, London, UK.

Communication Product

U.S. EPA. (2009) Doub, S. “National Risk Management Research Laboratory Brochure.” (EPA/600/F-09/004).

Upcoming Events

EPA Invites You to an Open House for the ETV Program, October 13, 2009, Cincinnati, OH

You will need Adobe Reader to view some of the files on this page.
See EPA's PDF page to learn more.