PAHs pollution in the outdoor air of areas with various land uses in the industrial city of Iran: distribution, source apportionment, and risk assessment

Abstract

Shahryar city regions with various land uses had their outdoor air concentrations of PM2.5-bound PAHs determined. Totally, 32 samples were taken - eight samples from the industrial region air (IS), eight samples from the high-traffic urban regions air (HTS), eight samples from the air of commercial regions (CS), and eight samples from residential areas (RS), which were analyzed by GC-MS. According to the study's findings, in the outdoor air of IS, HTS, CS, and RS, there were mean ƩPAHs concentrations of 23.25 ± 20.22, 38.88 ± 26.53, 6.97 ± 4.26, and 4.48 ± 3.13 ng/m3, respectively. As comparison to CS and RS, mean concentration of ƩPAHs in samples from HTS and IS was substantially greater (p < 0.05). Using the Unmix.6 receptor model, sources of PAHs in the air of Shahryar were allocated. The model's results show that 42% of PAHs come from diesel vehicles and industrial activities, 36% from traffic and other transportation sources, and 22% from heating sources and coal burning. The carcinogenicity suffering resulting from exposure to PAHs was as follows: This value for children of the ingestion, inhalation pathways and dermal contact is (1.90 × 10−6-1.38 × 10−4), (5.5 × 10−11-2.67 × 10−9) and (2.36 × 10−6-1.72 × 10−4), respectively. Also, for adults were (1.47 × 10−6 - 1.07 × 10−4), (1.14 × 10−10 - 5.27 × 10−9) and (3.68 × 10−6- 2.87 × 10−4), respectively. In general, the analyzed region's carcinogenicity risk estimates fell within the range of acceptable limit.