Analysis of lead pollution sources in roadside soil based on the isotope tracing method

Abstract

Abstract With the accelerated pace of road construction, road traffic sources are becoming one of the main sources of environmental heavy metals pollutants in addition to industrial pollution sources. Studies have shown that the heavy metals pollutants generated during transportation mainly include lead (Pb) and other elements. Most studies have focused on the characteristics and distribution patterns and qualitative source analysis of heavy metals pollution in roadside soils. However, systematic quantitative analysis of heavy metals in roadside soils and the atmosphere has not yet been achieved, which makes it difficult to effectively support the prevention and management of heavy metals pollution in roadside soils. Therefore, in this study, to clarify the sources of Pb in the roadside atmosphere and soils and their relative contributions, roadside atmospheric dustfall, sediment and soil samples were collected in industrial and nonindustrial areas, and the Pb isotopic values of the samples were determined via inductively coupled plasma–mass spectrometry (ICP‒MS). The sources of Pb in the roadside atmosphere and soil samples were quantified by isotope tracing. The results showed that vehicle emissions contributed the most to Pb in the roadside atmosphere, followed by road sediment and natural atmospheric dustfall, with contributions of 43%-49%, 35%-40% and 15%-17%, respectively. Roadside atmospheric dustfall contributed the most to Pb in roadside soil, followed by road sediment, with contributions of 68%-69% and 31%-32%, respectively, in nonindustrial areas and 61%-62% and 38%-39%, respectively, in industrial areas. The study results provide a basis for the prevention and control of Pb pollution in roadside soils.