Sponsor
This article was developed under Assistance Agreement No. R840238 awarded by the U.S. Environmental Protection Agency to Elliott Gall, Portland State University. It has not been formally reviewed by EPA. The views expressed in this document are solely those of Aurélie Laguerre and Elliott Gall and do not necessarily reflect those of the Agency. EPA does not endorse any products or commercial services mentioned in this publication. This work was partially supported by a seed grant from the Sloan Surface Consortium for Chemistry of Indoor Environments (SURF-CIE).
Published In
Environmental Science & Technology
Document Type
Post-Print
Publication Date
12-18-2023
Subjects
Wildfires -- Health aspects, Indoor air pollution, Persistent pollutants -- Bioaccumulation
Abstract
Wildfire smoke contains PAHs that, after infiltrating indoors, accumulate on indoor materials through particle deposition and partitioning from air. We report the magnitude and persistence of select surface associated PAHs on three common indoor materials: glass, cotton, and mechanical air filter media. Materials were loaded with PAHs through both spiking with standards and exposure to a wildfire smoke proxy. Loaded materials were aged indoors over ~4 months to determine PAH persistence. For materials spiked with standards, total PAH decay rates were 0.010±0.002, 0.025±0.005, and 0.051±0.009 d -1 , for mechanical air filter media, glass, and cotton, respectively. PAH decay on smoke-exposed samples is consistent with that predicated from decay constants from spiked materials. Decay curves of smoke loaded samples show PAH surface concentrations are elevated above background for ~40 days after the smoke clears. Cleaning processes efficiently remove PAHs, with reductions of 71% and 62% after cleaning smoke-exposed glass with ethanol and a commercial cleaner, respectively. Laundering smoke- exposed cotton in a washing machine and heated drying removed 48% of PAHs. An exposure assessment indicates that both inhalation and dermal PAH exposure pathways may be relevant following wildfire smoke events. Synopsis: Wildfire smoke events load indoor materials with PAHs that persist at elevated concentrations for weeks after the air clears, creating previously unrecognized inhalation and dermal exposure pathways. Cleaning activities meaningfully reduce PAH levels on smoke exposed indoor materials. Keywords: Indoor air quality, persistent organic pollutants, partitioning, biomass burning, surface chemistry
Rights
This document is the Accepted Manuscript version of a work that is set to appear in final form in Environmental Science & Technology, copyright © ACS, after peer review and technical editing by the publisher, with 12 month embargo. To access the final edited and published work see https://pubs.acs.org/journal/esthag OR upon publication, PSU affiliates may access the journal contents through the Library's subscription:
Environmental Science & Technology
DOI
10.1021/acs.est.3c05547
Persistent Identifier
https://archives.pdx.edu/ds/psu/41029
Citation Details
Laguerre, A. and Gall, E.T. Polycyclic aromatic hydrocarbons (PAH) in wildfire smoke accumulate on indoor materials and create post-smoke event exposure pathways. Environmental Science & Technology, 10.1021/acs.est.3c05547