Polycyclic aromatic hydrocarbon (PAH) exposure among European adults: Evidence from the HBM4EU aligned studies

Polycyclic aromatic hydrocarbons (PAHs) are persistent environmental pollutants with well-documented associations to adverse health effects, posing significant public health challenges across Europe. Human exposure to 13 urinary PAH metabolites was assessed in a harmonized cohort of European adults aged 20-39, representing diverse geographic regions across Europe: North (Iceland and Denmark), East (Poland and the Czech Republic), South (Croatia and Portugal), and West (France, Germany, Switzerland, and Luxembourg). This study aimed to achieve a unified understanding of PAH exposure by employing stringent participant selection criteria and harmonizing biomarker analyses by utilizing high-quality analytical protocols across multiple laboratories in Europe. Key findings revealed consistently elevated metabolite levels in smokers compared to non-smokers, with naphthalene metabolites dominating the profiles over phenanthrene and fluorene derivatives. Country-specific analyses highlighted Poland as having the highest naphthalene metabolite concentrations, while Luxembourg exhibited elevated pyrene metabolite levels. Urbanization influenced exposure, with slightly higher metabolite concentrations in town populations compared to rural areas. While sex-based stratification revealed no marked differences, gender emerged as a significant covariate in regression models, with women generally displaying higher exposure to naphthalene metabolites. Educational level further stratified exposure, with lower education correlating with increased PAH levels. Multivariate linear regression identified key exposure factors, including sampling season (i.e., summer, winter, autumn, and spring), dietary habits e.g., smoked foods, and proximity to smoke-prone environments. This dataset provides a significant baseline for evaluating the European Commission's Chemicals Strategy for Sustainability (CSS) and underscores the utility of harmonized human biomonitoring studies in informing targeted public health interventions.