Concentrations, temporal variations, human exposures and source identifications of PCDD/fs from an urban site employing passive air samplers in Bursa, Türkiye

Polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzo-furans (PCDFs) are toxic, long-lasting pollutants that accumulate in human fat tissue, posing significant health risks. The obtained data were evaluated based on congener profiles and levels, possible sources, seasonal concentration changes, health risks and atmospheric transport. This study investigated atmospheric PCDD/F levels in an urban site from June 2022 to June 2023 using three passive air samplers (PASs) in Bursa, Türkiye. Monthly samples were taken using three passive air samplers. The findings demonstrated the utility of PAS as a cost-effective and reliable monitoring device. Seasonal average concentrations were 324.66 ± 51.87 fg/m³ in spring, 234.79 ± 57.57 fg/m³ in summer, 363.07 ± 77.99 fg/m³ in fall and 479.88 ± 73.20 fg/m³ in winter. The yearly mean concentration value was 341.50 ± 108.27 fg/m³. The measured concentrations in this study corresponded closely to those reported for regions with similar characteristics. The most dominant congeners observed during the sampling period were OCDD, OCDF, 1,2,3,4,6,7,8-HpCDF and 1,2,3,4,6,7,8-HpCDD. The measured concentrations indicated no threatening situation in the risk evaluation. Pollutant transport was determined to be mostly local, suggesting limited long-range movement after employing the Clausius-Clapeyron equation. Principal component analysis (PCA) identified vehicle emissions, residential heating and industrial combustion as key sources of PCDD/Fs. Seasonal variation and source analysis emphasized the effect of human activities and meteorological patterns. This study contributes to understanding urban air pollution and supports future efforts to manage PCDD/F emissions in similar regions.