Reducing Toxic Metal Transfer to Food Crops from Contaminated Soils

Present guidelines for urban gardens are based solely on soil total concentrations of toxic metals. These are clearly inadequate, as our recent work in urban gardens shows only a weak dependency of vegetable lead content on the soil concentration of lead. This indicates that a more in-depth understanding is needed of the processes by which food crops are contaminated.To this end, the specific research objectives of the present project are to:Determine the exact mechanisms by which toxic elements, especially lead and arsenic, contaminate food crops, and identify sources of the contaminants.Explain the large differences observed in toxic metal accumulation by different crop types.Assess the effectiveness of soil remediation techniques, particularly stabilization by soil amendments such as composts, in reducing toxic metal transfer into vegetables.