Pollution characteristics and health risks of heavy metals in road dust in Ma'anshan, China

Road dust contains various heavy metals, which are re-suspension in the air under the action of wind and other external forces, threatening people's health all the time. Road dust was collected in the industrial heavy traffic area (IHT), non-industrial heavy traffic area (HT), urban area (UA), and study recreation area (SR) of Ma'anshan. The pollution degree of heavy metals in the four areas was calculated and demonstrated IHT > HT > UA > SR. In addition to the Ni (24.24 mg kg(-1))metals, the metals concentrations of Cr (74.14 mg kg(-1)), Cu (91.8 mg kg(-1)), Zn (393.03 mg kg(-1)), Cd (9.93 mg kg(-1)), and Pb (72.85 mg kg(-1)) were all higher than the local soil background values. Cu comes from traffic emissions, Pb, Cd, and Zn mainly come from industrial emissions, as well as traffic emissions. While Cr and Ni mainly come from industrial emissions and local soil re-suspension. The non-carcinogenic risk of each heavy metal to children is 10 times higher than that of adults. Among them, the non-carcinogenic risk of Cr, Cd, and Pb to children is close to 1, so great attention should be paid to it. According to the study of enrichment factor (EF) and geo-accumulation index (I-geo), Cd is extremely polluted and it is imperative to reduce Cd pollution.

Automated summary

Road dust is a constant threat to people's health as it contains various heavy metals that become airborne due to wind and external forces. Heavy metals pollution was calculated in four different areas, with industrial heavy traffic area (IHT) showing the highest pollution degree, followed by non-industrial heavy traffic area (HT), urban area (UA), and study recreation area (SR). The concentrations of Cr, Cu, Zn, Cd, and Pb in the road dust exceeded local soil background values, with Cu coming from traffic emissions and Pb, Cd, and Zn mainly from industrial emissions. Cr and Ni primarily originated from industrial emissions and soil re-suspension. The non-carcinogenic risk of heavy metals, especially Cr, Cd, and Pb, to children is a matter of concern, and urgent actions are needed to reduce Cd pollution based on the findings of enrichment factor and geo-accumulation index.