Soil profile from Sylling in Norway. Photo: Tor Erik FinneFor the contaminant lead (Pb) a method exists to distinguish different sources of origin based on the analysis of the ratios between the natural isotopes 206Pb, 207Pb og 208Pb.
One of the most used metals
Lead (Pb) is one of the most used metals in human history, and has been exploited for more than five thousand years for metallurgical, medicinal, and industrial purposes.
The cumulative production of lead until the year 2000 is estimated at 260 million tons, and 85% of this production has occurred over the past two hundred years. The global production per year was about 3 million tons at the end of the last century.
Contaminated by lead
It is commonly assumed that the terrestrial ecosystem over all of Norway is moderately to strongly contaminated by lead and other trace elements that have been transported in the atmosphere over long distances mainly from other parts of Europe.
Especially the southernmost part of Norway is strongly influenced (studies by for example Amundsen et al. 1992; Steinnes et al. 1992, 1994, 2005a). Lead mines around the world exhibit different ratios between the natural isotopes 206Pb, 207Pb og 208Pb.
Lead transported by long range atmospheric processes or in the air from local sources based on industrially produced (i.e. imported) lead will tend to have another ratio amongst these isotopes compared with the local (geogenic) lead source.