Ecological Risk Assessment for Heavy Metals in Agricultural Soils Surrounding Dumps, Huancayo Province, Peru

Contamination generated by dumps is an environmental problem because the soils around the dumps are used for the cultivation of agricultural products and pastures, and could constitute a threat to human health. The contamination index and ecological risk potential for heavy metals in agricultural soils surrounding the solid waste dumps in Agua de las Vírgenes (AV) and El Eden (ED) in Huancayo were evaluated. The concentration of heavy metals in the soils was measured using an inductively coupled optical emission spectrophotometer. The average concentration of As, Cd, Cr, Pb, Cu, Fe and Zn in the soils was 25.77, 1.03, 6.09, 112.07, 48.52, 53733.33 and 349.10 mg/kg in AV and 14.35, 0.28, 2.85, 123.01, 57.47, 36137.50 and 414.31 mg/kg in ED respectively. The mean values of the contamination factor for As determined a very high soil contamination status at both sites. The order of mean Igeo values was As> Cd> Pb> Zn> Cu> Fe> Cr. The soils are strongly enriched with As and Cd. The highest risk index was for Cd, with a higher contribution to the overall potential risk index. The principal component analysis explained that 71% of the data set and the identified sources of heavy metals are the varied composition of wastes in general and crop irrigation with wastewater. In general, agricultural soils are characterized for a level of ecological risk that varies from high to very high. Among the measured heavy metals As, Cd and Pb pose significant health risks. Continuous monitoring of the level of contamination of soils affected by dump leachate and wastewater irrigation is suggested