Review and future perspectives on soil and groundwater inorganic contamination by non-sanitary landfills in Latin America

The inappropriate disposal of municipal solid waste is a serious environmental problem and is related to contamination of several environmental matrices. This is still a recent issue, especially in developing countries. In this study, a critical systematic review on soil and groundwater contamination in sites of inadequate municipal solid waste disposal in Latin American countries is presented, indicating future prospects. 50 articles were selected, including 70 non-sanitary landfills in 59 different cities. A thorough study on the concentrations of contaminants in soil and groundwater is presented, including a joint qualitative analysis of the different sites and statistical analysis. Groundwater has been significantly affected, with 100% of sites with contaminants above the most restrictive standard. Surface soils were less affected, with 52.9%. Lead was found to be the parameter that most affected groundwater (39.1% of sites) and soil (25.5% of sites), followed by other metals, such as copper and zinc, which should be observed in risk analysis and remediation of these areas. It was observed that the contamination is more related to geological and geotechnical conditions and waste management. This study showed that despite the advances in the formulation of public policies in the years 2000-2010, more effective actions by governments in Latin American countries should be carried out to restrain the irregular disposal of municipal solid waste as well as to monitor and remediate the affected sites. In this sense, future perspectives and a series of actions related to waste management are suggested in the article.