Non-essential metal contamination in Ecuadorian agricultural production: A critical review

Non-essential metal contamination is a common issue worldwide. In the last decades, the primary contamination sources have been associated mainly with anthropogenic activities, but non-essential metals are also naturally present in the ecosystem. The latter applies to the Andean region, where various "contaminant" elements from volcanic and subsoil sources are present. In Ecuador, non-essential metal contamination in crops has gained attention in the last three decades and has been the focus of both domestic and international studies on agri-cultural products. Because of globalized commerce and demand for healthier products, international regulations regarding maximum permissible limits for certain metallic elements are becoming increasingly rigorous, requiring production systems that guarantee food safety. While Ecuador has specific regulations, they are not comprehensive for all non-essential metal contaminants that are harmful in certain amounts. Further, existing regulations are not fully enforced, and government control systems are inefficient, which increases the pop-ulation's possibility of exposure to pollutants. This review compiles and discusses results from studies on metal contamination, their availability in the environment, translocation in vegetables, and consumption-related health problems to evaluate whether current Ecuadorian agricultural product regulations ensure food quality and safety in terms of non-essential metal pollution.