Comprehensive assessment of environmental and health risks of metal(loid)s pollution from non-ferrous metal mining and smelting activities

Abstract

Abandoned non-ferrous metal mining and smelting sites have left a degraded environmental legacy, threatening the ecosystem and human health, particularly by the presence of As, Cd, Pb, and Cu as major contaminants. The health of the metal-contaminated soils was assessed by combining physicochemical parameters and microbial metabolism activity analyses. Low microbial metabolic activity indicated that soil microorganisms were inhibited by the presence of heavy metals. The content and speciation distribution of metals were closely linked to the measured microbial metabolic indicators. The invertase (INV) activity and peak time (Tpeak) were identified as sensitive bio-indicators for assessing soil health conditions. Combination environmental assessment (CEA) pollution, considering the total content and chemical form of metal(loid)s, revealed Cd, As, Pb, and Cu all reached high pollution degrees at the surrounding area, while Cr, Mn, Sb, Zn, Ni, and V were low pollution degrees. Different research sites ranked by potential ecological risk index (RI) as follows Pollution site (24621.22) > East site (19330.32) > West site (12989.49) > South site (9281.05), while different sites were sorted in reverse order by microbial indicators. The analyses revealed that the main human health risk was linked to As, threatening the local population with non-carcinogenic and carcinogenic hazards, particularly for children.