title: Including exposure variability in the life cycle impact assessment of indoor chemical emissions: the case of metal degreasing.
abstract: The present paper describes a method that accounts for variation in indoor chemical exposure settings and accompanying human toxicity in life cycle assessment (LCA). Metal degreasing with dichloromethane was used as a case study to show method in practice. We compared the human toxicity related to the degreasing of 1m(2) of metal surface in different exposure scenarios for industrial workers, professional users outside industrial settings, and home consumers. The fraction of the chemical emission that is taken in by exposed individuals (i.e. the intake fraction) was estimated on the basis of operational conditions (e.g. exposure duration), and protective measures (e.g. local exhaust ventilation). The introduction of a time-dependency and a correction for protective measures resulted in reductions in the intake fraction of up to 1.5 orders of magnitude, compared to application of existing, less advanced models. In every exposure scenario, the life cycle impacts for human toxicity were mainly caused by indoor exposure to metal degreaser (>60%). Emissions released outdoors contributed up to 22% of the life cycle impacts for human toxicity, and the production of metal degreaser contributed up to 19%. These findings illustrate that human toxicity from indoor chemical exposure should not be disregarded in LCA case studies. Particularly when protective measures are taken or in the case of a short duration (1h or less), we recommend the use of our exposure scenario-specific approach.
authors: Radboud University Nijmegen, Department of Environmental Science, PO Box 9010, 6500 GL Nijmegen, The Netherlands. Electronic address: l.golsteijn@science.ru.nl.
authors: Laura
authors: L
authors: Golsteijn
authors: Radboud University Nijmegen, Department of Environmental Science, PO Box 9010, 6500 GL Nijmegen, The Netherlands; Caesar Consult Nijmegen, PO Box 31070, 6503 CB Nijmegen, The Netherlands.
authors: Daan
authors: D
authors: Huizer
authors: Radboud University Nijmegen, Department of Environmental Science, PO Box 9010, 6500 GL Nijmegen, The Netherlands.
authors: Mara
authors: M
authors: Hauck
authors: Radboud University Nijmegen, Department of Environmental Science, PO Box 9010, 6500 GL Nijmegen, The Netherlands.
authors: Rosalie
authors: R
authors: van Zelm
authors: Radboud University Nijmegen, Department of Environmental Science, PO Box 9010, 6500 GL Nijmegen, The Netherlands.
authors: Mark A J
authors: MA
authors: Huijbregts
mesh_terms: D000395:Air Pollutants, Occupational / Q000032:analysis / Q000633:toxicity*; D016902:Air Pollution, Indoor / Q000331:legislation & jurisprudence / Q000706:statistics & numerical data*; D006801:Humans; D008669:Metallurgy; D008670:Metals / Q000737:chemistry*; D008752:Methylene Chloride / Q000032:analysis / Q000633:toxicity*; D008954:Models, Biological; D016273:Occupational Exposure / Q000706:statistics & numerical data*; D018570:Risk Assessment / Q000379:methods
chemical_list: D000395:Air Pollutants, Occupational; D008670:Metals; D008752:Methylene Chloride
keywords: Consumer health; Exposure scenario; Indoor air; Intake fraction; Life cycle assessment (LCA); Occupational toxicology