A comprehensive assessment of heavy metals, VOCs and petroleum hydrocarbon in different soil layers and groundwater at an abandoned Al/Cu industrial site

• Published in: Ecotoxicology and environmental safety Vol. 284; p. 116927
• Main Authors: Wu, Jing, Jiang, Jinfeng, Xu, Changlin, Cai, Yue, Li, Min, Yang, Yang, Yang, Guoyi, Meng, Xiang-Zhou, Leib, JinMing, Zhangb, Hao, Zhang, Shengwei
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier Inc 01.10.2024; Elsevier
• Subjects: Al/Cu industrial sites; Aluminum - analysis; Compound pollution; Copper - analysis; Environmental Monitoring; Groundwater; Groundwater - chemistry; Hydrocarbons - analysis; Metals, Heavy - analysis; Petroleum - analysis; Potentially toxic elements; Soil; Soil - chemistry; Soil Pollutants - analysis; Volatile Organic Compounds - analysis; Water Pollutants, Chemical - analysis; Soil; Groundwater; Al/Cu industrial sites; Compound pollution; Potentially toxic elements
• ISSN: 0147-6513; 1090-2414; 1090-2414
• DOI: 10.1016/j.ecoenv.2024.116927

Compound pollution at industrial sites impedes urban development, especially when there is a lack of understanding about the spatial variations of internal pollution in industrial areas producing light-weight materials. In this study, spatial distribution and ecological risks of potentially toxic elements (PTEs), volatile organic compounds (VOCs), and petroleum hydrocarbons (C10–40) in the soil and groundwater of an Al/Cu (aluminum/copper) industrial site have been analyzed comprehensively. Results revealed the progressive clustering of pollutants in different soil layers, which indicated varying levels of penetration and migration of pollutants from the surface downward. Furthermore, severity of pollution varied according to pollutant type, with Cu (5–10,228 mg kg−1) often exceeding the background levels significantly (>40). Cd (0.03–2.60 mg kg−1) and Hg (0.01–3.73 mg kg−1) were found at elevated concentrations in deeper soil layers, suggesting distinct variations of PTEs across different soil depths. Among the more hazardous VOCS, polychlorinated biphenyls (1.80–234 μg kg−1) were particularly prevalent in the deeper layers of soil. Petroleum hydrocarbons (C10–40) were widely detected (6–582 mg kg−1), showing significant migration potential from surface to deep soil. These findings suggest that prolonged industrial activities lead to deep-seated accumulation of pollutants, which also impacts the groundwater, contributing to long-term dispersion of contaminants. Furthermore, multivariate statistical analysis indicated certain positive correlations among the distribution of Cu, Pb and petroleum hydrocarbons, indicating possible coupling of these pollutants. Severe Cu pollution caused an ecological risk in the surface soil layer (covering >20 % area of high pollution site, contributing >40 % ecological risk). While the Hg and Cd posed significant risks in the deeper soil layers, showing higher risk coefficients and mobility. The study provides crucial insights into the transformation of urban areas with a history of industrial uses into community spaces and highlights the risks posed by the remaining pollutants. •Extreme Cu residues diffused throughout various soil layers in the site.•Heavy metals, VOCs, and C10–40 showed a high spatial heterogeneity.•Several heavy metals posed a severe ecological risk in the deeper soil layers.•Petroleum hydrocarbons, Cu and Pb presented a high correlation and compound pollution.•Soil pollution and groundwater pollution do not always align.