Summary

Environmental study
The lead and zinc mine at Maarmorilik stopped production in 1990. Since then the environment around the site has been monitored by analysing for lead and zinc in seawater, plants and animals. This report presents the results of environmental studies conducted in 2002 and assesses the state of the environment in the area. The results are compared with data from 1975-2000.

Dust
The lead and zinc dispersal with dust around Maarmorilik has been monitored by use of the lichen Cetraria nivalis. This species is used to monitor dust dispersal, as the only take-up of water, nutrients and pollutants is from the surface of the lichen. The lead and zinc concentration in lichens after one year of transplantation to locations at Maarmorilik has been used as a measure of metal dispersal as dust. From this study we have found elevated lead levels in lichens in the areas around Affarlikassaa and Qaamarujuk, whereas the area affected by zinc is smaller. There is no clear time trend in the lead and zinc levels in lichens from the area in the period 1997 to 2002.

Seawater
The pollution of seawater has changed drastically since mine closure, after which only small amounts of lead are released from settled tailings and waste rock in the fiord Affarlikassaa. Zinc is still released, but clearly less than when mining took place. In the bottom water of the fiord, the lead concentration was about 1000 times and the zinc concentration about 14 times lower in 2002 than in 1988-89. Metal concentrations in surface waters of Affarlikassaa have also declined significantly and in 2002 we did not find elevated lead and zinc concentrations here. This was also the case in 1999-2000.

Seaweed
Brown algae in the tidal zone take up metals from surrounding water and may be used to monitor seawater pollution. In seaweed the lead concentration has remained unchanged from 2000 to 2002, while the zinc concentration decreased. Over the entire monitoring period (1982-2002) both the lead and zinc concentration has decreased, and lead levels have decreased more than zinc levels. Since 1990 - after mine closure - lead and zinc levels have decreased in most areas, mostly pronounced in Affarlikassaa, close to Maarmorilik and below the Black Angel mountain. However, there are also areas where zinc levels are unchanged after mine closure, particularly in the inner and northern part of Qaamarujuk.

Blue mussels
Also blue mussels from the tidal zone take up metals from seawater algae and particles. In blue mussels sampled in 2002 lead levels above background are found in Affarlikassaa, Qaamarujuk and Perlerfiup Kangerlua. Elevated zinc levels are found in a smaller area, only in Qaamarujuk. The lead and zinc concentrations in blue mussels have been declining over a number of years, but lead levels only slowly, because the mussels cannot eliminate all the lead taken up originally. The study shows that new blue mussel generations (small mussels) contain significantly less lead than older, larger mussels. We also measure the pollution by transplanting blue mussels from a clean site to the Maarmorilik region and analyse their lead and zinc content one year or more years later. These studies show that the tidal zone still is affected by lead and zinc pollution after mine closure, but the impact is steadily declining and is significantly lower than when mining took place.

Fish and prawns
In muscle tissue from capelin, spotted wolffish and shorthorn sculpin caught at Maarmorilik in 2002 the lead concentration is low. Liver tissue from spotted wolffish and shorthorn sculpin are analysed to monitor the time trend of the lead pollution. In 2002 we found elevated lead concentrations in the livers of both species. The level is similar to what we have found after mine closure and during the last years of mining. In prawns from Qaamarujuk the lead concentration is elevated in 2002. The lead concentration is significantly higher in the heads and shells than in meat. Since 1988 lead levels in prawns have been clearly declining, but most in the beginning of this period.

Human health risks
The cases where elevated lead levels in marine organisms were found at Maarmorilik in 2002 are assessed not to imply health risks for humans, except in blue mussels. Lead concentrations in blue mussels are still so high that it is recommended not to collect and eat blue mussels from Affarlikassaa, Qaamarujuk and Perlerfiup Kangerlua.

Overall conclusion
The environmental studies conducted in 2002 show that pollution sources still exist at Maarmorilik 12 years after mine closure in 1990. However, over a number of years lead and zinc levels in seawater and biota have decreased, in particular after the mine closed, and the area affected by pollution with lead and zinc has become smaller and smaller over the years.

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