Investigating Arsenic, Lead and Mercury Accumulation in Culturally Relevant Crops and Low-Cost Environmental Public Health Intervention Strategies.

Metal uptake by plants may pose health risks to human that feed on crops grown near mining sites. The focus of this study is on the accumulation of As, Pb, and Hg in specific crops. This experiment will be a two-part greenhouse study. The first step investigates the ability of sesame, corchorus, lentil and arugula to accumulate As, Pb and Hg in their edible tissue.  These plants were selected due to their cultural relevance, worldwide consumption, and representation of a broad range of plant families. The treatments will consist of mining waste from Iron King Mine and Humboldt Smelter Superfund Site mixed with a commercially available garden soil. The above crops will be grown in four treatments with 0%, 25%, 50% and 75% mining waste. Crops that are commonly consumed cooked, such as corchorous leaves and lentil seeds will be traditionally prepared (e.g. boiled) to examine the effects of cooking on metal accumulation.  The second step of the project is designed to investigate the effectiveness of phyto-protection using known metal-hyperaccumulators. A sesame, corchorus, lentil, or arugula plant will be grown with a hyperaccumulator in the same treatments as explained above. Both the crops and hyperaccumulator will be analyzed (as described above) to determine whether the hyperaccumulator reduced the crop’s As, Pb, and Hg uptake. The first step of the project will elucidate the uptake pattern of As, Pb and Hg by culturally relevant crops and whether preparation and cooking effects metal accumulation. For the second phase of this project, it is anticipated that this work will provide a low-cost public health intervention strategy for farmers and communities to use when growing crops in soils that have an elevated concentration of As and heavy metals.