Removal of lead from soils contaminated with mining tailings through vermicomposting

Canales Gutiérrez A.; Belizario Quispe G.; Chui Betancur H.; Roque Huanca B. · Revista de Investigaciones Agropecuarias (2022)

Resumen

Mining tailings from small informal mining contaminate soil and water resources with heavy metals. The objective of the work was to evaluate the efficiency of vermicomposting in the removal of Pb from soils contaminated with mining tailings. The mining tailings samples were from the La Rinconada mine, Peru, at 5200 m altitude. The mining tailings were mixed with agricultural land, sheep manure and wood sawdust, in variable amounts and proportions, for three treatments of three replicates each. The concentration of Pb in the treatments was 61.70, 52.64 and 45.90 mg of mixture; however, the three treatments had the same amount of Pb (188.20 mg), to which 25, 50 and 75 red worms (Eisenia foetida) were inoculated. Controls were made at 40, 60 and 80 days. 80 days after vermicomposting, Pb concentrations decreased (p < 0.05) to 56.8±1.0; 24.4±0.6 and 21.3±0.7 mg/kg mixture. The amounts of residual Pb were 173±3.0, 87.3±2.1 and 87.1±2.9 mg. The percentages of Pb removed were 7.9±1.6, 53.6±1.1 and 53.7±1.5 mg/kg, respectively, in relation to the initial 188.20 mg/kg of lead. Based on the results, it is concluded that vermicomposting can be a feasible technology for the removal of Pb from soils contaminated with mining tailings.

Instituciones: Universidad Nacional del Altiplano