Environmental impact of lead in soybeans (Glycine max L.) marketed in the canton of Quevedo, Ecuador

The bioaccumulation of lead in soybean crops, originating in contaminated soils, represents a significant environmental problem and a risk to public health due to the inherent toxic metal. The objective of this study was to evaluate the environmental impact of lead in samples of soybeans (Glycine max L.) marketed in the canton of Quevedo, Ecuador. Grain samples were collected randomly, in triplicate, from four local markets during a period of [indicate period] and a control sample from a non-contaminated cultivation area. The samples were subjected to a preparation process that included drying, grinding, acid digestion with concentrated HNO₃ and HCl, and dilution. Lead determination was carried out by electrothermal atomization atomic absorption spectrometry (GFAAS). The calculation of the lead contamination index was performed using a standardized equation, contrasting the results obtained with the maximum allowable limits established by national (NTE INEN 452:2013) and international (Codex Alimentarius, European Union) regulations. The results evidenced an average concentration of lead in the soybean samples of 1.15 ± 0.13 mg.kg-1, significantly exceeding the maximum allowable limits. The calculated contamination index indicated a high level of contamination in the analyzed grains, which represents a risk to both the ecosystem and human health when consumed. These findings underscore the need to implement environmental and food management strategies to reduce lead contamination in soybean crops, thus ensuring food safety and public health protection.