Several metals are toxic and have adverse effects on health and the environment, even in very low concentrations (trace amounts). Some examples of these are:

  • Lead
  • Cadmium
  • Mercury
  • Chromium
  • Copper
  • Arsenic

Most metals are taken up by plants and herbivorous animals, where they accumulate. There is both natural and anthropogenic sources of metals in the atmosphere.

Examples of anthropogenic sources are combustion of fossil fuels, metallurgical industry and waste incineration. Long-range transport of various metals from emissions in Europe contribute significantly to the metal concentrations in the southern part of Norway.


Mercury is one of the most hazardous substances and poses a threat to the environment and human health. Mercury has received much attention because it is toxic, has a long life time, and bioaccumulate in the food chain. This means that the mercury could eventually end in our food, especially in the Arctic areas.

Mercury has both natural and anthropogenic sources. Mercury contamination in Norway is caused by both national emissions and pollution from other parts of the world. In the atmosphere, mercury can be transported over long distances. This means that the contaminant can be transported by air currents far from its sources to remote areas like the Arctic and Antarctic.

Read also:

NILU's mercury research

The Historic Uses of Mercury