NO2 levels inside vehicle cabins with pollen and activated carbon filters: A real world targeted intervention to estimate NO2 exposure reduction potential

Matthaios, Vasileios N; Rooney, Daniel; Harrison, Roy M; Koutrakis, Petros; Bloss, William J

Abstract

Traffic related nitrogen dioxide (NO2) poses a serious environmental and health risk factor in the urban environment. Drivers and vehicle occupants in general may have acute exposure to NO2 levels. In order to identify key controllable measures to reduce vehicle occupant's exposure, this study measures NO2 exposure inside ten different vehicles under real world driving conditions and applies a targeted intervention by replacing previously used filters with new standard pollen and new activated carbon cabin filters. The study also evaluates the efficiency of the latter as a function of duration of use. The mean in-vehicle NO2 exposure across the tested vehicles, driving the same route under comparable traffic and ambient air quality conditions, was 50.8 ± 32.7 μg/m3 for the new standard pollen filter tests and 9.2 ± 8.6 μg/m3 for the new activated carbon filter tests. When implementing the new activated carbon filters, overall we observed significant (p < 0.05) reductions by 87 % on average (range 80 - 94.2 %) in the in-vehicle NO2 levels compared to the on-road concentrations. We further found that the activated carbon filter NO2 removal efficiency drops by 6.8 ± 0.6 % per month; showing a faster decay in removal efficiency after the first 6 months of use. These results offer novel insights into how the general population can control and reduce their exposure to traffic related NO2. The use and regular replacement of activated carbon cabin air filters represents a relatively inexpensive method to significantly reduce in-vehicle NO2 exposure.

Citation

Matthaios, V. N., Rooney, D., Harrison, R. M., Koutrakis, P., & Bloss, W. J. (2023). NO2 levels inside vehicle cabins with pollen and activated carbon filters: A real world targeted intervention to estimate NO2 exposure reduction potential. Science of the Total Environment, 860, Article 160395. https://doi.org/10.1016/j.scitotenv.2022.160395

• Journal Article Type: Article
• Acceptance Date: Nov 17, 2022
• Publication Date: Feb 20, 2023
• Deposit Date: Sep 26, 2023
• Publicly Available Date: Sep 28, 2023
• Journal: Science of The Total Environment
• Electronic ISSN: 1879-1026
• Publisher: Elsevier
• Peer Reviewed: Peer Reviewed
• Volume: 860
• Article Number: 160395
• DOI: https://doi.org/10.1016/j.scitotenv.2022.160395
• Public URL: https://nottingham-repository.worktribe.com/output/24425794
• Publisher URL: https://www.sciencedirect.com/science/article/pii/S0048969722074976?via%3Dihub
• Additional Information: This article is maintained by: Elsevier; Article Title: NO2 levels inside vehicle cabins with pollen and activated carbon filters: A real world targeted intervention to estimate NO2 exposure reduction potential; Journal Title: Science of The Total Environment; CrossRef DOI link to publisher maintained version: https://doi.org/10.1016/j.scitotenv.2022.160395; Content Type: article; Copyright: © 2022 The Authors. Published by Elsevier B.V.