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

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.
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.
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