Impact of ancient iron smelting wastes on current soils: Legacy contamination, environmental availability and fractionation of metals

Characterization and risk assessment of soil around waste rock heaps affected by acid rock drainage in an abandoned pyrite mining area

“…Thus, arsenic with 99.9% occurring in the residual fraction is not considered to be available to the environment in natural conditions. As reported by previous studies, many kinds of iron-bearing minerals have been found in the soil of mining areas, such as Schwertmannite and goethite, and these minerals have good performance in the stabilization of As (Amnai et al, 2021). Considering the relatively low bioavailability of PTEs and limited exposure routes, the human health risk of the soil surrounding the waste heap is generally acceptable.…”

“…It is found that both geological background and mining activities contribute to the high metal levels in mining areas (Wang et al, 2020). Given the potential remobilization of accumulated metals, these acidic soils can be considered a secondary pollution source (Amnai et al, 2021). Therefore, both the waste rocks and their surrounding soils need to be treated if their environmental risk is high (Tabelin et al, 2020;Ódri et al, 2020).…”

Bioavailability Assessment of Heavy Metals Using Various Multi-Element Extractants in an Indigenous Zinc Smelting Contaminated Site, Southwestern China

“…For instance, Lee et al indicated that the concentrations of Zn, Pb, Cd, and Cu in soils near a large Zn smelter displayed a significant decrease with depth, and these smelter-derived metals were vertically migrated to 60 cm below the surface soils during the past 46 year zinc smelting [28]. Amnai et al reported that the highest concentrations of Co, Cu, Fe, Mn, Ni, and Zn in the topsoils from slag heaps in an ancient iron smelting site were found up to 60, 20, 130,000, 8000, 60, and 250 mg/kg, respectively [29]. Li et al found that As, Cd, Pb, and Zn in ground dust from a typical Chinese indigenous zinc smelting area were about ten times greater than those in other non-smelting cities [30].…”

Predicting the Bioaccessibility of Soil Cd, Pb, and As with Advanced Machine Learning for Continental-Scale Soil Environmental Criteria Determination in China

“…15−18 While several research groups have evaluated the health risks of site pollutants based on oral bioavailability/ bioaccessibility, they predominantly relied on limited, sitespecific pollutant data. 19,20 To date, the absence of nationwide investigations means that regional variations in PHE bioaccessibility on a continental level and their subsequent implications for health risk evaluations are yet to be fully understood.…”

“…Currently, oral bioavailability is gauged by comparing metal accumulations in animal tissues or urine, with these animals being exposed to soluble reference compounds such as sodium arsenate (NaH 2 AsO 4 ), lead acetate (Pb(AC) 2 ), or cadmium chloride (CdCl 2 ). − Owing to the substantial costs and ethical dilemmas linked with animal testing, the assessment of bioaccessibilitythe proportion of heavy metals extracted in vitro from gastric simulations relative to their total contenthas been widely explored as an alternative for appraising PHE bioavailability. This approach not only circumvents the limitations of animal-based tests but has also been corroborated by them and extensively applied in research. − While several research groups have evaluated the health risks of site pollutants based on oral bioavailability/bioaccessibility, they predominantly relied on limited, site-specific pollutant data. , To date, the absence of nationwide investigations means that regional variations in PHE bioaccessibility on a continental level and their subsequent implications for health risk evaluations are yet to be fully understood.…”