Association of polycyclic aromatic hydrocarbons in moss with blood biomarker among nearby residents in Portland, Oregon

PLOS ONE RESEARCH ARTICLE Association of polycyclic aromatic hydrocarbons in moss with blood biomarker among nearby residents in Portland, Oregon Igor Burstyn1*, Geoffrey H. Donovan2, Yvonne L. Michael1, Sarah Jovan2 1 Dornsife School of Public Health, Drexel University, Nesbitt Hall, Philadelphia, Pennsylvania, United States of America, 2 USDA Forest Service, PNW Research Station, Portland, Oregon, United States of America a1111111111 a1111111111 a1111111111 a1111111111 a1111111111 OPEN ACCESS Citation: Burstyn I, Donovan GH, Michael YL, Jovan S (2022) Association of polycyclic aromatic hydrocarbons in moss with blood biomarker among nearby residents in Portland, Oregon. PLoS ONE 17(12): e0279207. https://doi.org/10.1371/ journal.pone.0279207 Editor: Fung-Chi Ko, National Dong Hwa University, TAIWAN Received: May 4, 2022 Accepted: December 1, 2022 * Abstract Polycyclic aromatic hydrocarbons (PAHs) are air pollutants that are costly to measure using traditional air-quality monitoring methods. We used an epiphytic bio-indicator (moss genus: Orthotrichum) to cost-effectively evaluate atmospheric deposition of PAHs in Portland, Oregon in May 2013. However, it is unclear if measurements derived from these bioindicators are good proxies for human exposure. To address this question, we simultaneously, measured PAH-DNA adducts in blood samples of non-smokers residing close to the sites of moss measurements. We accounted for individual determinants of PAH uptake that are not related to environmental air quality through questionnaires, e.g., wood fires, consumption of barbecued and fried meats. Spearman rank correlation and linear regression (to control for confounders from the lifestyle factors) evaluated the associations. We did not observe evidence of an association between PAH levels in moss and PAH-DNA adducts in blood of nearby residents (e.g., all correlations p�0.5), but higher level of adducts were evident in those who used wood fire in their houses in the last 48 hours. It remains to be determined whether bio-indicators in moss can be used for human health risk assessment. Published: December 19, 2022 Peer Review History: PLOS recognizes the benefits of transparency in the peer review process; therefore, we enable the publication of all of the content of peer review and author responses alongside final, published articles. The editorial history of this article is available here: https://doi.org/10.1371/journal.pone.0279207 Copyright: This is an open access article, free of all copyright, and may be freely reproduced, distributed, transmitted, modified, built upon, or otherwise used by anyone for any lawful purpose. The work is made available under the Creative Commons CC0 public domain dedication. Data Availability Statement: Data contain potentially identifying or sensitive information, and therefore under ethical clearance that permitted conduct of the study and as part of informed 1. Introduction Polycyclic aromatic hydrocarbons (PAHs) are a class of air pollutants, some of which are linked to adverse health outcomes [1, 2]. PAHs are by-products of the incomplete combustion of organic matter, including tobacco products, fossil fuels and firewood, and are abundant in smoked, fried, or grilled food. Risk management requires understanding pathways of exposure, best done though comparing environmental measurements that reflect different sources to measurements of internal dose through biomarkers. Cost-effective methods to accurately evaluate exposures to PAH are lacking, unlike that for total particle matter, typically employed in air pollution research and regulations. Lichen and moss are among the most commonly used bio-indicators of atmospheric PAHs and can accumulate both particle and gas-phase PAHs [3, 4]. Their leaves and lobes lack cuticles, allowing PAHs to diffuse easily into cells [5] and a high-surface area traps particles [6]. In PLOS ONE | https://doi.org/10.1371/journal.pone.0279207 December 19, 2022 1/7 PLOS ONE consent, we are not able to share that data, IRB Protocol Number 1402002647. However, there are some circumstances under which we can be compelled to share data. Such requests should be made to the Human Research Protection Program (HRPP) that is responsible for providing administrative and regulatory support to the Drexel University Institutional Review Boards (IRB), via email . Funding: The author(s) received no specific funding for this work. Competing interests: I, Igor Burstyn, have read the journal’s policy and the authors of this manuscript have the following competing interests: Igor Burstyn is an expert witness in a litigation that concerns matters related to use of lichen and moss as indicators of human exposure and risk. This does not alter our adherence to PLOS ONE policies on sharing data and materials. All other authors have declared that for them no competing interests exist. PAH moss contamination and human exposure addition, lichen and moss do not have roots, making them dependent on atmospheric sources of nutrients and water and, therefore, bioaccumulation reflects airborne sources of PAHs. Lichens and moss contain levels of mid-to-high molecular weight PAHs that correlate with nearby stationary air-quality monitors in studies conducted by different groups across diverse locations [3, 6, 7]. Jovan et al. [8] demonstrated that moss can be used to cost-effectively map the distribution of PAHs across residential areas of Portland, Oregon, which correlated with both traffic and tree canopy cover; earlier related research on metals indicated the same moss species, Orthotrichum lyellii [9], can be used to identify sources of such pollution [10]. It is uncertain how PAH levels in lichens and moss relate to doses received by humans. To increase our understanding of this critical question, we conducted a follow-up study to Jovan et al. (2021) investigating the relationship between levels of PAHs in moss and that of PAH-DNA adducts in the blood of nearby residents. 2. Materials and methods 2.1 Study area and sampling strategy Portland is a city in northwest Oregon, USA; Orthotrichum lyellii is the only species of moss or lichen that is common across a wide variety of sites in Portland. Participants were non-smokers residing with non-smokers recruited though an email list distributed to employees of US Forest Service’s Pacific Northwest Research Station located in Portland. Smokers self-identified as is appropriate in human health research among trusted volunteers who had no reason to conceal if they smoked. We did not ask about health because there is no a priori reason why health would impact levels of PAH in blood and moss on properties, thereby introducing confounding. We collected moss samples in May of 2013 on hardwood trees located on properties of study participants, from a height of at least 1 meter to reduce the influence of spray from cars and from dog urine. We recorded the location of each sample point using a (...truncated)