title: Categorization framework to aid exposure assessment of nanomaterials in consumer products.
abstract: Exposure assessment is crucial for risk assessment for nanomaterials. We propose a framework to aid exposure assessment in consumer products. We determined the location of the nanomaterials and the chemical identify of the 580 products listed in the inventory maintained by the Woodrow Wilson International Center for Scholars, of which 37% used nanoparticles suspended in liquids, whereas <1% contained "free airborne nanoparticles". C(60) is currently only used as suspended nanoparticles in liquids and nanosilver is used more as surface bound nanoparticles than as particles suspended in liquids. Based on the location of the nanostructure we were able to further group the products into categories of: (1) expected, (2) possible, and (3) no expected exposure. Most products fall into the category of expected exposure, but we were not able to complete a quantitative exposure assessment mainly due to the lack of information on the concentration of the nanomaterial in the products--a problem that regulators and industry will have to address if we are to have realistic exposure assessment in the future. To illustrate the workability of our procedure, we applied it to four product scenarios using the best estimates available and/or worst-case assumptions. Using the best estimates available and/or worst-case assumptions we estimated the consumer exposure to be 26, 15, and 44 microg kg(-1) bw year(-1) for a facial lotion, a fluid product, and a spray product containing nanoparticles, respectively. The application of sun lotion containing 2% nanoparticles result in an exposure of 56.7 mg kg(-1) bw d(-1) for a 2-year-old child, if the amounts applied correspond to the European Commission recommendations on use of sunscreen.
authors.affiliation: Department of Environmental Engineering, NanoDTU Environment & Health, Technical University of Denmark, DTU-Building 113, Kgs Lyngby 2800, Denmark. sfh@env.dtu.dk
authors.forename: Steffen Foss
authors.initials: SF
authors.lastname: Hansen
authors.forename: Evan S
authors.initials: ES
authors.lastname: Michelson
authors.forename: Anja
authors.initials: A
authors.lastname: Kamper
authors.forename: Pernille
authors.initials: P
authors.lastname: Borling
authors.forename: Frank
authors.initials: F
authors.lastname: Stuer-Lauridsen
authors.forename: Anders
authors.initials: A
authors.lastname: Baun
mesh_terms: D003257:Consumer Product Safety; D003358:Cosmetics; D004781:Environmental Exposure; D015386:Hazardous Substances; D006801:Humans; D049329:Nanostructures; D018570:Risk Assessment / Q000379:methods; D013473:Sunscreening Agents
chemical_list: D003358:Cosmetics; D015386:Hazardous Substances; D013473:Sunscreening Agents