| Title: | Indoor ozone/human chemistry and ventilation strategies |
| Author(s): | Salvador CM; Beko G; Weschler CJ; Morrison G; Le Breton M; Hallquist M; Ekberg L; Langer S; |
| Address: | "Department of Chemistry and Molecular Biology, Atmospheric Sciences, University of Goteborg, Goteborg, Sweden. International Centre for Indoor Environment and Energy, Department of Civil Engineering, Technical University of Denmark, Lyngby, Denmark. Environmental and Occupational Health Sciences Institute, Rutgers University, Piscataway, NJ, USA. Department of Environmental Sciences and Engineering, Gillings School of Global Public Health, The University of North Carolina at Chapel Hill, Chapel Hill, NC, USA. CIT Energy Management AB, Goteborg, Sweden. Division of Building Services Engineering, Department of Architecture and Civil Engineering, Chalmers University of Technology, Goteborg, Sweden. IVL Swedish Environmental Research Institute, Goteborg, Sweden" |
| ISSN/ISBN: | 1600-0668 (Electronic) 0905-6947 (Print) 0905-6947 (Linking) |
| Abstract: | "This study aimed to better understand and quantify the influence of ventilation strategies on occupant-related indoor air chemistry. The oxidation of human skin oil constituents was studied in a continuously ventilated climate chamber at two air exchange rates (1 h(-1) and 3 h(-1) ) and two initial ozone mixing ratios (30 and 60 ppb). Additional measurements were performed to investigate the effect of intermittent ventilation ('off' followed by 'on'). Soiled t-shirts were used to simulate the presence of occupants. A time-of-flight-chemical ionization mass spectrometer (ToF-CIMS) in positive mode using protonated water clusters was used to measure the oxygenated reaction products geranyl acetone, 6-methyl-5-hepten-2-one (6-MHO) and 4-oxopentanal (4-OPA). The measurement data were used in a series of mass balance models accounting for formation and removal processes. Reactions of ozone with squalene occurring on the surface of the t-shirts are mass transport limited; ventilation rate has only a small effect on this surface chemistry. Ozone-squalene reactions on the t-shirts produced gas-phase geranyl acetone, which was subsequently removed almost equally by ventilation and further reaction with ozone. About 70% of gas-phase 6-MHO was produced in surface reactions on the t-shirts, the remainder in secondary gas-phase reactions of ozone with geranyl acetone. 6-MHO was primarily removed by ventilation, while further reaction with ozone was responsible for about a third of its removal. 4-OPA was formed primarily on the surfaces of the shirts (~60%); gas-phase reactions of ozone with geranyl acetone and 6-MHO accounted for ~30% and ~10%, respectively. 4-OPA was removed entirely by ventilation. The results from the intermittent ventilation scenarios showed delayed formation of the reaction products and lower product concentrations compared to continuous ventilation" |
| Keywords: | "Air Pollutants/*analysis Air Pollution, Indoor/*analysis Aldehydes/analysis Built Environment Clothing Environmental Monitoring/methods Humans Ketones/analysis Mass Spectrometry/methods Oxidation-Reduction Ozone/*analysis Skin/*chemistry Terpenes/analysis;" |
| Notes: | "MedlineSalvador, Christian Mark Beko, Gabriel Weschler, Charles J Morrison, Glenn Le Breton, Michael Hallquist, Mattias Ekberg, Lars Langer, Sarka eng P30 ES010126/ES/NIEHS NIH HHS/ Research Support, Non-U.S. Gov't England 2019/08/20 Indoor Air. 2019 Nov; 29(6):913-925. doi: 10.1111/ina.12594. Epub 2019 Sep 15" |
