Baseline concentrations and quantitative health risk assessment of polycyclic aromatic hydrocarbons (PAHs) in relation to particle grain size in street dust of Warsaw Poland.

Total concentrations, toxicity, and health risks of 16 polycyclic aromatic hydrocarbons (PAH) in street dust from Warsaw (Poland) in 6 granulometric fractions were investigated. Street dust was collected from 149 sampling points distributed among Area 1 (central districts, left bank of the Vistula River, mostly traffic-related pollution) and Area 2&3 (suburb area, mostly residential, right bank of the river). Street dust was investigated before ("all") and after separating into 5 size-dependent samples: (1-0.8 mm) "0.8", (0.8-0.6 mm) "0.6", (0.6-0.4 mm) "0.4", (0.4-0.2 mm) "0.2", and (below 0.2 mm) " < 0.2". ΣPAH mean concentration was 3.21 mg/kg for Area 1 and 0.89 mg/kg for Area 2&3. ∑BaP values calculated collectively for Area 1&2&3 were observed to be 318.3, 83.5, 131.1, 81.4, 164.3, and 339.7 ng/g for "all", "0.6", "0.4", "0.2", and " < 0.2", respectively. Significant differences in ∑BaP values were observed between fractions and specific areas. The cancer risk levels for children and adults, for all particulate size fractions, were comparable for dermal contact and by ingestion and ranged from 10 to 10, whereas the cancer risk levels via inhalation always ranged from 10 to 10. Therefore, inhalation of resuspended street dust is almost negligible compared to other pathways. Environmental implication. Street dust pollution in cities is one of the most important issues in the world and it negatively affects the quality of the environment and people's health. This study contributed to filling the gap in knowledge about the characteristics of PAH contaminants in the subject of the grain size of street dust from Poland and assessing the potential health risks. Therefore, our work has provided new significant information on PAH pollution, methods of measuring PAHs content and assessing the risk to human health, which may be useful to the scientific community, policymakers, and the general public.