Changing pattern of exposure to polycyclic aromatic hydrocarbons over time in the Central European population

BackgroundTemporal trends of chemicals in the population are key to identifying changing sources of chemicals and determining the effectiveness of various legislative measures.ObjectiveThe present study focused on time comparisons to explore a possible decrease in PAH metabolite levels in the Czech population. Legislative measures occurred between sampling periods, including restricting smoking and the Air Protection Act.MethodsTen metabolites of PAHs were measured in urine samples collected in 2011-2012 from mothers and children from DEMOCOPHES-CZ study (N = 235) and in 2019-2020 from children, teenagers, and young adults from CELSPAC studies (N = 809). Multivariate linear regression, Kruskal-Wallis ANOVA, and Mann-Whitney test (MW) were used to investigate differences in OH-PAHs between periods, age categories, and exposure determinants.ResultsMedian concentrations significantly decreased between 2011-2020 by 30-35% for 1-OH-NAP, 2-and 3-OH-FLUO, 85% for 1-OH-PHE, and 44% for 2/3-OH-PHE, while 2-OH-NAP increased by 29% in non-smoking adults. In children, median concentrations of all metabolites decreased by 10-51%, with 2-OH-NAP rising by 49%. Smokers showed the largest differences, with significant decreases of 46-59% in the median concentrations of 2-OH-NAP, 2/3-OH-PHE, 9-OH-PHE, and 1-OH-PYR, and 76-91% in OH-FLUOs, 1-OH-NAP, and 1-OH-PHE. Fish and offal consumption, season, locality, and type of cooking were significant factors associated with levels of OH-PAHs, explaining 4-9% of the variability. Smoking was the main contributor in 2011, explaining up to 45% variability; no difference was found between smokers and non-smokers in 2019. New reference values of OH-PAHs in urine were calculated for the Czech population.ImpactThis study analyses the temporal trends of OH-PAHs in the population in the context of introduced legislative measures. In addition, it examines OH-PAH exposure in children, adolescents, and young adults in relation to lifestyle factors and establishes new reference values for polycyclic aromatic hydrocarbons that are important for public health decision-making. Biomonitoring over time is an essential tool for establishing new measures to protect public health.Created in BioRender. Komprdova, K. (2025) https://BioRender.com/u10q831.ImpactThis study analyses the temporal trends of OH-PAHs in the population in the context of introduced legislative measures. In addition, it examines OH-PAH exposure in children, adolescents, and young adults in relation to lifestyle factors and establishes new reference values for polycyclic aromatic hydrocarbons that are important for public health decision-making. Biomonitoring over time is an essential tool for establishing new measures to protect public health.Created in BioRender. Komprdova, K. (2025) https://BioRender.com/u10q831.