Lead and Cadmium in Plants 1991


Ingestion of heavy metals in foodstuffs makes up a substantial proportion of total contamination in humans. Heavy metals in food or feed crops are ingested through the food chain directly or indirectly by humans and partially accumulated in the human body.

Lead and cadmium are among the most abundant heavy metals and are particularly toxic. Exceeding toxic threshold values can effect health. Cadmium can disturb kidney functions, and some studies indicate a cancerous effect (Merian 1984). Lead is less toxic. But very high lead levels in children’s blood were shown to have an inhibiting effect on certain enzymes (Scheffer/Schachtschabel 1989). High contamination levels of each element in plants cause growth disorders and reduction of crop yields.

Health risks resulting from consumption of contaminated foodstuffs for any given individual can only be estimated for individual persons, depending on nutritional habits, degrees of contamination in the personal environment (smoking, workplace), and personal physical predispositions.

One goal of precautionary environmental policies should be the prevention of polluting areas used for cultivating food and feed crops; to avoid or minimize the accumulation of contaminants in plants in polluted areas by the use of appropriate soil cultivation and the selection of suitable crops. Knowledge about pollutants in cultivated food and feed crops in the Berlin metropolitan area is a prerequisite to effectively advise users.