Title: | Indoor Dust/Air Partitioning: Evidence for Kinetic Delay in Equilibration for Low-Volatility SVOCs |
Author(s): | Parnis JM; Taskovic T; Celsie AKD; Mackay D; |
Address: | "Chemical Properties Research Group (CEMC), Department of Chemistry, Trent University, Peterborough, Ontario K9L 0G2, Canada" |
ISSN/ISBN: | 1520-5851 (Electronic) 0013-936X (Linking) |
Abstract: | "Effective modeling of semivolatile organic chemical (SVOC) partitioning between air and indoor dust is investigated by calculating partition ratios for selected SVOCs between air and n-octanol as well as 8 other oligomers similar in chemical structure to common components of household dust. COSMO-RS solvation theory was used to calculate air-oligomer partition ratios, which were converted to estimates for K(OA) (octanol-air) and K(dust-air). The results are compared with reported monitored partition ratios with good agreement for the more volatile SVOCs of vapor pressure (VP) exceeding 10(-5) Pa and corresponding calculated log K(dust-air) (m(3) g(-1)) of <5.5 or unitless log K(OA) of <11.5. For less volatile SVOCs, reported values of K(DA) are significantly lower than predicted, with the deviation increasing with decrease in VP. This effect is attributed to a kinetic delay in which characteristic times for equilibration exceed the dust-air contact time, and equilibrium is not achieved. It is hoped that the approach of computing partition ratios of SVOCs using oligomers selected on the basis of likely dust sources and compositions may improve the estimation of indoor human exposure to SVOCs present in air and dust and assist in exploiting dust samples to monitor and evaluate the fate and exposure of organic chemicals used indoors" |
Keywords: | "*Air Pollution, Indoor Dust Humans Kinetics *Volatile Organic Compounds/analysis Volatilization;" |
Notes: | "MedlineParnis, J Mark Taskovic, T Celsie, Alena K D Mackay, Donald eng Research Support, Non-U.S. Gov't 2020/05/01 Environ Sci Technol. 2020 Jun 2; 54(11):6723-6729. doi: 10.1021/acs.est.0c00632. Epub 2020 May 12" |