| Summary: | Lead and cadmium are toxic elements, which are a natural part of earth crust. They are taken up from the soil and transferred upwards in the plant and animal food chain. Cadmium is widely distributed throughout the natural environment with human activities having an important role in its dispersion into the biosphere. The natural sources of cadmium are volcanic eruptions and old granite rocks, which are an important geochemical source. Anthropogenic sources of cadmium are related mainly to mining, fertilizers and atmospheric deposition. Leaded gasoline has been most important source of atmospheric lead. However, most countries have now prohibited the use of leaded gasoline. This action has greatly reduced emissions of lead into the atmosphere. Anthropogenic sources of lead other than traffic are typically fossil fuel combustion, non-ferrous metal production and iron and steel production. Zinc and copper are important constituents in a number of different enzyme functions in man and animals. Zinc and copper reach the environment via industrial releases involving production and refining of metals. In 1997 emissions of heavy metal particulates were only a third of their values in the early 1990s due to the installation of sulphur removal systems. In this study lead, cadmium, copper and zinc levels in Finnish game animals (moose, hares) and farmed game animal (reindeer) were studied during twenty years period. About 500 moose were collected between 1980 and 1999 from south western, southern, central and south eastern Finland. About the same number of Mountain and European hare samples were collected during the period 1980 and 1993 from south western, southern, south eastern and northern Finland. About 300 reindeer were collected in 1990–1992 from southern, eastern, western and northern Lapland. After these initial projects, it was decided to collect moose and reindeer samples every year as part of national residue control program; fifteen moose and ten reindeer per year. In this residue control program, also cattle ...
|
|---|