Potential Heavy Metals Pollution Contribution from Wash-Off of Urban Road-Dust

Based on the different particle sizes of street dust, the potential pollution load of heavy metals from dry and wet atmospheric deposition to surface runoff in different functional areas of Zhengzhou city was estimated by using the rain-scour heavy metal index model. Compared to the EA, IA, and CA areas, RA and PA have a higher potential contribution to heavy metal runoff pollution from Road deposited sediments (RDS) than the other watersheds. Zhengzhou utilized the RDS index model to calculate pollution loads in various areas around Zhengzhou (EA, IA, CA, PA, and RA). In the different land-use areas, the RDS indices for pollutant load (RDSindex,load) and pollutant strength (RDSindex,strength) varied greatly, and the RDSindex strength values increased. RDSindex,load fell in the following order: IA > RA > PA > EA. Because the RDS index incorporates RDS characteristics such as the amount of RDS, grain sizes present, RDS mobility, and associated metals, the RDSindex,load and RDS(index,strength )results did not merely match variability in the amounts of RDS found or metal concentrations in the RDS in various land-use areas. Metal's presence in the dust is a direct health risk for humans and warrants immediate and effective pollution control and prevention measures in the city.

Automated summary

This study estimated the potential pollution load of heavy metals from street dust to surface runoff in different functional areas of Zhengzhou using the rain-scour heavy metal index model. It was found that the rural area and industrial area had a higher contribution to heavy metal runoff pollution. The indices for pollutant load and pollutant strength varied greatly in different land-use areas.