Feasibility of cultivating Se-enriched crops using localized natural Se enrichment resources

Selenium (Se) exists in a dispersed state with low abundance in the environment, of which nutritional supply is generally inadequate globally. Cultivating Se-enriched crops using limited natural Se resources may be a feasible solution to mitigate this inadequacy. Herein, maize grain and Chinese cabbage harvested from a representative area with localized Se enrichment were selected. Concentration level and enrichment mechanism of Se were investigated. Results indicated that Se concentrations in the crops cultivated in the subareas influenced by Se-enriched bedrock weathering or industrial contamination can reach the enrichment level. Gray relation analysis results suggested that Se concentrations were mainly controlled by bioavailable fraction of Se in soil. The subordinate factors included chemical weathering degree and pH condition of cultivated soil, redox potential of irrigation water and atmospheric deposition. A Monte Carlo simulation-based health risk assessment verified the feasibility of cultivating Se-enriched crops without substantial health risk under regional Se-deficient background.