Coupled near-field and far-field exposure assessment framework for chemicals in consumer products.
Humans can be exposed to chemicals in consumer products through product use and environmental emissions over the product life cycle. Exposure pathways are often complex, where chemicals can transfer directly from products to humans during use or exchange between various indoor and outdoor compartments until sub-fractions reach humans. To consistently evaluate exposure pathways along product life cycles, a flexible mass balance-based assessment framework is presented structuring multimedia chemical transfers in a matrix of direct inter-compartmental transfer fractions. By matrix inversion, we quantify cumulative multimedia transfer fractions and exposure pathway-specific product intake fractions defined as chemical mass taken in by humans per unit mass of chemical in a product. Combining product intake fractions with chemical mass in the product yields intake estimates for use in life cycle impact assessment and chemical alternatives assessment, or daily intake doses for use in risk-based assessment and high-throughput screening. Two illustrative examples of chemicals used in personal care products and flooring materials demonstrate how this matrix-based framework offers a consistent and efficient way to rapidly compare exposure pathways for adult and child users and for the general population. This framework constitutes a user-friendly approach to develop, compare and interpret multiple human exposure scenarios in a coupled system of near-field ('user' environment), far-field and human intake compartments, and helps understand the contribution of individual pathways to overall human exposure in various product application contexts to inform decisions in different science-policy fields for which exposure quantification is relevant.
Quantitative Sustainability Assessment Division, Department of Management Engineering, Technical University of Denmark, Produktionstorvet 424, 2800 Kgs. Lyngby, Denmark. Electronic address: pefan@dtu.dk.
Peter
P
Fantke
Quantitative Sustainability Assessment Division, Department of Management Engineering, Technical University of Denmark, Produktionstorvet 424, 2800 Kgs. Lyngby, Denmark.
Alexi S
AS
Ernstoff
Environmental Health Sciences, University of Michigan, 1415 Washington Heights, Ann Arbor, MI 48109-2029, USA.
Lei
L
Huang
Oak Ridge Institute for Science and Education hosted at the U.S. Environmental Protection Agency, National Risk Management Research Laboratory, Cincinnati, OH 45268, USA.
Susan A
SA
Csiszar
Environmental Health Sciences, University of Michigan, 1415 Washington Heights, Ann Arbor, MI 48109-2029, USA.
Olivier
O
Jolliet
D003358:Cosmetics / Q000032:analysis*; D004781:Environmental Exposure; D004784:Environmental Monitoring / Q000379:methods*; D005430:Floors and Floorcoverings; D006801:Humans; D008962:Models, Theoretical; D018570:Risk Assessment / Q000379:methods
D003358:Cosmetics
Chemical alternatives assessment; High-throughput risk screening; Life cycle impact assessment; Multimedia multi-pathway framework; Near-field consumer exposure; Product intake fraction