Heavy metals are ubiquitous and chemically stable, so they can be expected to be present in all parts of the biotic and abiotic matter. The pathway within the food chain starts in case of cadmium in the soil via roots to plants, in case of lead by the air dust and in case of arsenic and mercury in the polluted water. During the transfer from one link in the chain to another some heavy metals may be accumulated up to the final link, man. To avoid an increase of unwanted toxic heavy metals in food for human consumption it is necessary to limit the concentrations in the lower links of the food chain, i.e. in water and soil, by establishing tolerable levels or by a limitation of industrial emissions.
Key words
- Heavy metals
- food chain
- food toxicology