Evaluation of the content of metals and contamination indices generated by environmental liabilities, in Tacna, Peru

Abstract

Abstract Abandoned mines are environmental liabilities with a high potential for contamination of rivers, soils, and entire ecosystems, which constitutes a threat to wildlife, flora, and fauna, in addition to socio-environmental, economic, and human health risks. The objective of this study was to determine the degree of contamination of 5 abandoned mines to evaluate their potential environmental and social impact. The presence and concentration of arsenic, barium, cadmium, lead, chromium, mercury, and free cyanide by mass spectrometry, and hexavalent chromium by ion chromatography. The environmental indices of geoaccumulation, contamination factor, and contamination load were used to evaluate the level of contamination for each area. The results showed high contamination with a high content of arsenic (2,046 mg Kg− 1), cadmium (650 mg Kg− 1), lead (26,131 mg Kg− 1), free cyanide (92 mg Kg− 1), mercury (26.4 mg Kg− 1) above the established maximum limits, not detecting the presence of hexavalent chromium (0.03 mg Kg− 1). In Peru, there are many abandoned mines, so it is a latent danger of an environmental disaster. Therefore, it is essential to assess heavy metal contamination together with environmental risks, to establish efficient mitigation measures.