Decreasing lead levels in Swedish biota revealed by 36 years (1969-2004) of environmental monitoring.

Since the 1980s, lead levels decreased significantly in most marine biota from the Baltic Sea, the Kattegatt and the Skagerrack and in terrestrial biota from south and central Sweden, analysed in the National Swedish Environmental Monitoring Programme. In herring and cod liver, the decrease was 4.2-7.1% annually 1981-2003 and in perch liver and guillemot eggs analysed since the middle of the 1990s the decrease was 10-13%. In kidneys of young starlings from south and central Sweden, lead levels decreased 6.2-12% annually and the annual decrease in liver and kidney from young moose was 8.8% and 6.5%, respectively. In northern Sweden, lead levels decreased in pike liver by 2.8% between 1969 and 1994 and in reindeer liver by 3.5% annually while a significant increase (5% annually 1981-1994) has been detected in arctic char. In some marine biota, there were indications of a larger decrease during the last ten years compared to the whole period. The large decline in lead emission to the atmosphere during the last twenty years, mainly because of decreasing use of leaded gasoline has obviously resulted in decreasing lead levels in biota.