Traces of pollutants are found throughout the arctic environment: in air, soil, sediments, snow, sea ice and glaciers, seawater and fresh water, birds, mammals and people. In many ways, the Arctic acts as an indicator region for known and new pollutants. Researchers and authorities are concerned about high concentrations of certain types of pollutants measured in the Arctic.

Scientists and the authorities are concerned about the high concentrations of certain kinds of pollutants measured in the Arctic.

PCB values from air measurements at the Zeppelin Observatory in Ny-Ålesund in Svalbard show higher levels than at corresponding stations in Canada, suggesting that the European Arctic receives more PCB than the North American Arctic. The PCB levels in polar bears in Svalbard are 2–6 times higher than in polar bears from Alaska and Canada. The polar bear also has higher levels of certain kinds of brominated flame retardants.

Scientists have also found a number of “new” pollutants, like various types of brominated and fluorinated substances, in the air in Svalbard.

Air pollution

Atmospheric pollution is monitored in the Norwegian part of the Arctic at the Zeppelin Observatory in Ny-Ålesund. The monitoring focuses on compounds associated with acidification and top dressing, greenhouse gases, organic pollutants and heavy metals.

Acid precipitation

Acid precipitation was a major environmental problem until around the 1970s. The problem is caused by nitrogen and sulphur compounds in the atmosphere, and subsequent acid precipitation. Such precipitation caused forests to die, and top dressing could result in changes in the composition of the vegetation; for instance, moss could be out-competed by grass. Sulphur is a greater problem than nitrogen in the Arctic. Experience has shown that discharges from Russia and to some extent Eurasia are the principal sources of sulphur and nitrate compounds measured in the Norwegian part of the Arctic.

An evaluation in the 1990s revealed that about 5 % of ice-free areas with vegetation showed effects of acid precipitation. The discharges have been substantially reduced since then, and measurements of sulphur compounds at the Zeppelin Observatory showed a reduction of as much as 61 % from 1980 to 2010.

Heavy metals

Heavy metals are emitted in connection with traffic and industry. In nature, heavy metals affect both people and wildlife. For instance, lead is acutely toxic to aquatic organisms and mammals, harming foetuses and having immunological effects. The Zeppelin Observatory measurements show that lead levels were reduced by 30 % from 1994 to 2010. The shift from leaded to unleaded petrol contributed to this reduction worldwide. Measurements of cadmium and mercury do not show corresponding trends in the Arctic, probably because the global circulation patterns continue to supply the Arctic with these heavy metals from distant sources where industrial activity is high.

Persistent organic pollutants

Persistent organic pollutants (POPs) are a special problem for wildlife in the Arctic because they are fat-soluble and arctic animals are dependent upon stores of fat to insulate them against the cold. The POPs accumulate in the fatty tissue and are liberated to other parts of the body when the animal is starving or fasting.

POPs are measured at the Zeppelin Observatory, and 2011 stood out by having the lowest ever annual mean for several of the most common POPs, such as PCB?. HCB? has increased a little in Arctic air masses each year since 2007.

According to the Management plan for Lofoten and the Barents Sea (2010), these waters are clean and rich in life, and have a low level of pollution. The reprocessing plants for nuclear waste at Sellafield and Cap de la Hague are sources of technetium-99, a radioactive isotope?. Seawater in Kongsfjorden in Svalbard and off Jan Mayen is monitored to try to track nuclear waste emissions. Technetium-99 emissions rose greatly in the mid-1990s and this was reflected in the measurements, but they have declined since then.

Trends

The levels of contaminants in the Arctic vary in both time and space. Contaminants that are transported in the atmosphere follow the seasonal fluctuations of the air masses, and levels therefore vary through the year. The levels of other contaminants vary as a result of efforts made by management authorities through international conventions, for example, and we can consequently see declining trends of contaminants in the Arctic.

Organic pollutants

Time trends for organic pollutants in the Norwegian part of the Arctic vary considerably, depending upon the substances and where they are measured. The air measurements show a rising trend for HCB, varying trends for PCBs and declining trends for HCH, [tooltip id={chlordanes}]chlordanes[/tooltip] and DDT. No trends have been observed for PBDE, PFAS or TBA, which have been monitored in the air since 2006.

Compared with other parts of the Arctic, high PCB levels have been measured in the air and in lake sediments from Svalbard. The PCB levels in wildlife from Norwegian arctic areas show a declining trend. However, PCBs are still the predominant contaminant in the Arctic. Since PCBs degrade slowly, they will remain in the environment for many more decades. The chlorinated herbicides show more varying trends, but the main trend seems to be declining levels. Groups of brominated compounds like PBDE and PBB have been observed to be declining, whereas other brominated compounds like α-HBCD are rising. The time trends for fluorinated compounds in the Arctic are not clear and vary from one to another.

Management measures such as bans and phasing out lead to reductions in emissions and transport. Substances like PCBs and chlorinated sprays are decreasing because bans on their manufacture and use have been introduced, whereas concentrations are increasing for substances that have not been banned internationally, for instance HBCD and some of the fluorinated compounds. The “new” contaminants which are discovered in the Arctic give grounds for concern and show that more substances than the traditional persistent organic pollutants (POPs) have a potential for long-range transport. The concentrations of polluting substances which have been banned and phased out are expected to decrease in the future. However, the manufacture and use of new compounds is constantly increasing and these may affect the arctic environment.

Heavy metals

The heavy metals, cadmium, mercury and lead, are regarded as challenging for arctic areas. Mercury discharges have been reduced in North America and Europe since the 1990s, whereas they have increased greatly in Asia. The reduction in the use of leaded petrol has been very effective in reducing lead pollution. Changes in the concentration of cadmium and mercury have not been measured at the Zeppelin Observatory at Ny-Ålesund in Svalbard since measurements started in 1994, but lead has declined by 30 %. There are lower quantities of heavy metals in lake sediments from Svalbard than from mainland Norway. Mercury and cadmium levels in wildlife from Svalbard are generally lower than from other parts of the Arctic.

Radionuclides

De viktigste kildene til menneskeskapt radioaktivitet har vært globalt nedfall fra atmosfæriske kjernefysiske våpentester, utslipp fra gjenvinningsanlegg i Europa og Tsjernobylulykken. Utslipp fra alle atomanlegg til The most important sources of anthropogenic radioactivity have been global fallout from nuclear weapon testing in the atmosphere, discharges from recycling plants in Europe and the Chernobyl disaster. On the whole, discharges from all nuclear plants to northern European waters have been reduced since the early 1990s, and levels of radioactivity are continually declining. The expected trend in the years to come is that the levels of anthropogenic radioactivity will continue to sink.

Geographical trend in wildlife

The geographical trends found in the Arctic fox corresponds with the trends found in the polar bear, with the highest contaminant values in East Greenland and Svalbard, moderate ones in Canada and the lowest ones in Alaska. Recent studies have shown that the levels of contaminants in arctic foxes are strongly related to where in the food chain they find their food and the proportion of marine and terrestrial food items in their diet, that is to say where they spend most of their time and what they eat. Results from Svalbard show that the levels of contaminants are highest in arctic foxes which find food high in the marine food chain.

The geographical differences in arctic foxes can also be related to the two different types of habitat arctic foxes live in, inland and coastal habitats. Foxes which have mostly eaten animals living on land (for instance, ptarmigan and reindeer) have lower PCB levels than those which have eaten animals living in the sea (for instance, seals). The high levels of contaminants in arctic foxes in Svalbard and Iceland can be explained by them having a more marine diet than those in Canada and Alaska.

Global restrictions

Global restrictions and phasing out of a number of pollutants such as PCBs, DDT, HCH and some brominated compounds and PFOS have been introduced. Time-series measurements in air and birds show that these substances have declined following the introduction of the global restrictions, but they will not disappear from the arctic regions. However, the trend is the opposite for new, unregulated pollutants, whose levels are rising in both the air and organisms.

The quantity and distribution of pollutants in the Arctic have been studied for many years, not least through the Arctic Monitoring and Assessment Programme (AMAP), one of six working groups under the Arctic Council.

Norway’s position in the Arctic gives the country a unique opportunity to be a leading manager of the environment in northern areas since the discovery of new pollutants in the Arctic is most important for regulating chemicals. This regulation takes place under the terms of the Stockholm Convention, through the EU REACH programme.

Effects of pollutants

Effects of pollutants have been found in animals high in the food chains in the Arctic. Impacts on the hormone and immune systems, reduced reproduction and increased offspring mortality are some of the effects found in the polar bearglaucous gull, arctic char and harp seal. Impaired immune system and reduced reproduction show that far-transported pollutants affect populations of arctic animals.

Sources and transport

The main sources of contaminants in the Arctic are regarded as being the fairly densely populated and industrialised parts of the world. The substances are transported to the Arctic in the atmosphere and by ocean currents, and also by rivers and ice in the Arctic. These are the most important means of transport, but pollutants carried by animals which move between the polar areas may also have some significance.