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Risk Analysis, Vol. 28, No. 2, 2008 DOI: 10.1111/j.1539-6924.2008.01017.x Estimating Consumer Exposure to PFOS and PFOA David Trudel, 1 Lea Horowitz, 1 Matthias Wormuth, 1 Martin Scheringer, 1∗ Ian T. Cousins, 2 and Konrad Hungerb ¨ uhler 1 Perfluorinated compounds have been used for more than 50 years as process aids, surfactants, and for surface protection. This study is a comprehensive assessment of consumer exposure to perfluorooctane sulfonate (PFOS) and perfluorooctanoic acid (PFOA) from a variety of environmental and product-related sources. To identify relevant pathways leading to consumer exposure to PFOS and PFOA a scenario-based approach has been applied. Scenarios represent realistic situations where age- and gender-specific exposure occurs in the everyday life of consumers. We find that North American and European consumers are likely to experience ubiquitous and long-term uptake doses of PFOS and PFOA in the range of 3 to 220 ng per kg body weight per day (ng/kg bw /day) and 1 to 130 ng/kg bw /day, respectively. The greatest portion of the chronic exposure to PFOS and PFOA is likely to result from the intake of contaminated foods, including drinking water. Consumer products cause a minor portion of the consumer exposure to PFOS and PFOA. Of these, it is mainly impregnation sprays, treated carpets in homes, and coated food contact materials that may lead to consumer exposure to PFOS and PFOA. Children tend to experience higher total uptake doses (on a body weight basis) than teenagers and adults because of higher relative uptake via food consumption and hand-to- mouth transfer of chemical from treated carpets and ingestion of dust. The uptake estimates based on scenarios are within the range of values derived from blood serum data by applying a one-compartment pharmacokinetic model. KEY WORDS: Consumer exposure; consumer products; exposure analysis; perfluorinated chemicals; PFOA; PFOS 1. INTRODUCTION Perfluorinated compounds (PFCs) occur glob- ally in wildlife and humans. (1) The most commonly studied PFC classes are the perfluorinated sul- fonates (PFSAs) and the perfluorinated carboxylates (PFCAs) and the most commonly measured com- pounds in these classes are perfluorooctane sulfonate (PFOS) and perfluorooctanoic acid (PFOA). Both 1 Institute for Chemical and Bioengineering, Wolfgang-Pauli-Str. 10, ETH Zurich, CH-8093 Zurich, Switzerland. 2 Department of Applied Environmental Science (ITM), Fresca- tiv ¨ agen 50, Stockholm University, SE-10691 Stockholm, Sweden. ∗ Address correspondence to Martin Scheringer, Institute for Chemical and Bioengineering, Wolfgang-Pauli-Str. 10, ETH Zurich, CH-8093 Zurich, Switzerland; tel: +41-44-632-3062; fax: +41-44-632 11 89; [email protected]. compounds are moderately toxic to mammals, (2,3) bioaccumulative, (1) and very persistent to abiotic and biotic degradation. (2,3) It has been proposed to classify PFOS as a persistent organic pollutant (POP) under the Stockholm Convention. (4) Both PFCAs and PFSAs have been produced for more than 50 years, (5) but have become of interest to researchers since the late 1990s. The increasing inter- est in these compounds is due to the recent advances in analytical methodology that has enabled their widespread detection in the environment and humans at trace levels. PFCs have been found in outdoor and indoor air, (6–9) surface and drinking water, (10–12) house dust, (8,13–15) animal tissue, (16,17) human blood serum, and human breast milk. (18,19) Because of the high per- sistence of PFOS and PFOA, the two compounds 251 0272-4332/08/0100-0251$22.00/1 C 2008 Society for Risk Analysis
