Transfer of Metals in Food Chain: An Example with Copper and Lettuce

Present study investigated the possible transfer of metals in the food chain (from soil to edible plants). The experiment was done with lettuce Lactuca sativa grown in different types of soil contaminated with copper (Cu²⁺) in various concentrations, with or without addition of humic substances. The highest content of copper was detected in lettuce samples grown in soils with lower levels of organic matter, thus indicating the importance of soil organics in metal transfer routes and accumulation rates in plants. It was found that copper accumulation in lettuce grown in contaminated soils can be significantly reduced by the addition of humic substances.