Distribution, Source, and Ecological Risk of Heavy Metals in Sewage Irrigation of Taiyuan, Shanxi Province, China

• Published in: Toxics (Basel) Vol. 12; no. 2; p. 120
• Main Authors: Zhao, Ying, Yan, Han, Wang, Fei
• Format: Journal Article
• Language: English
• Published: Switzerland MDPI AG 01.02.2024; MDPI
• Subjects: Agricultural land; Agricultural pollution; agriculture; Cadmium; Canals; Chromium; Contamination; Copper; Distribution; ecological risk; Ecological risk assessment; Environmental aspects; Environmental protection; Environmental quality; Food security; heavy metal; Heavy metals; Impaired water use; Industrial areas; Irrigation; Lead; Mercury; Mercury (metal); Metal concentrations; Pesticides; Pollutants; Pollution; Pollution control; Pollution index; Pollution levels; Risk assessment; Sampling; Sewage; Sewage irrigation; soil; Soil analysis; Soil contamination; Soil pollution; Soil quality; Soils; Sorghum; Taiyuan city; Testing; Wastewater irrigation; Zinc; China; Shanxi China; Taiyuan city; agriculture; sewage irrigation; heavy metal; soil; ecological risk
• ISSN: 2305-6304; 2305-6304
• DOI: 10.3390/toxics12020120

The pollution of agricultural soil by heavy metals is a significant environmental issue that has a serious impact on human health and food security. This study focused on investigating the presence of heavy metal pollution in sewage-irrigated soils in Taiyuan city. A total of 110 soil samples were analyzed for the presence of As, Hg, Cd, Pb, Cr, Cu and Zn. The results showed that the concentrations of these metals ranged from 0.06 to 26.74 mg/kg for As, 0.00 to 0.84 mg/kg for Hg, 0.03 to 0.69 mg/kg for Cd, 44.32 to 100.09 mg/kg for Pb, 9.85 to 42.19 mg/kg for Cr, 13.38 to 53.72 mg/kg for Cu, and 42.77 to 145.47 mg/kg for Zn. The average concentrations of these metals were found to be below the risk values specified in the "Soil environmental quality (GB15618-2018)", except for As and Cd in three sampling points in Xiaodian District. The heavy metal pollution in these areas can be attributed to various sources, such as industrial activities, the use of fertilizers and pesticides, and the irrigation process. According to the geo-accumulation index, the agricultural soil in the Taiyuan irrigation area was found to be uncontaminated by Zn, Cr, Cu, and As, and lightly contaminated by Cd, Hg, and Pb. The Nemerow Pollution Index indicated that the soil at all sampling points exhibited a slight level of pollution. Moreover, the ecological risk assessment indicated that all heavy metals posed a slight level of pollution. The findings of this study provide a scientific basis for the development of effective policies and measures for soil environmental protection and pollution control.