The levels of pollutants in Antarctica are, in general, lower than elsewhere in the world. This applies to those in the air, water, sediments, animals and plants, and is primarily because there is less industry and farming in the Southern Hemisphere. Because the pollutant problem has so far not been regarded as significant in Antarctica, there is no overall monitoring programme for pollutants here. There are currently few investigations of levels of pollutants in the Antarctic marine food chain. The Antarctic Peninsula and Ross Bay are the two most investigated areas.

Sources

Antarctica has no industry or agriculture and only a few settlements, all of which are research stations. Human activity otherwise is associated with fisheries and tourism. There are few local sources of pollution. The main sources are therefore areas on the Earth with a high population density and industrial activity. The contaminants are transported long distances by means of the circulation in the atmosphere and the ocean currents

Atmospheric transport

Smoke from forest fire

POLLUTION FROM SOUTH AMERICA Pollution from forest fires in Brazil reaches Antarctica four weeks later. Photo: Istockphoto

Atmospheric transport is the main means by which contaminants reach Antarctica. The closest sources are furthest south in South America. The Troll Observatory has been able to trace aerosols measured at Troll back to forest fires in Brazil four weeks earlier. Emissions from tropical regions therefore soon reach the north coast of the continent.

Pollution from research stations

Mann og beltevogn foran en rød bygning på påler

LOCAL POLLUTION The research stations contribute local pollution through discharges from domestic waste, effluent and incineration. Photo: Arne Oddvar Bergdahl / Norwegian Polar Institute

The research stations contribute very local pollution due to emissions and discharges of domestic waste, effluent and incineration. No systematic attempts have so far been made to model the consequences of local sources of pollution, including cruise ships and discharges in connection with scientific activities on the continental scale in Antarctica. However, studies at certain stations have recently focused increasingly on the contaminant load.

Enhanced PAH? levels, traceable to diesel aggregates, were found at the Argentinian Carlini Station (formerly Jubany). PAH levels, three times higher than in uninhabited areas, have been found in sediments near the Brazilian research station in Admiral Bay. Sediment samples from the vicinity of the American bases at McMurdo and Palmer have shown that the sediments are contaminated by both PCB?s and PAHs. Recent investigations at McMurdo and the Scott Base (New Zealand) have revealed brominated flame retardants in both the inside air and the effluent. All these compounds are typical contaminants in areas with human activity.

Trends

With few local sources, contaminant levels in Antarctica to some extent reflect global pollution trends. 

Analyses of snow and ice cores from Coats Land, Victoria Land and Law Dome have shown that Antarctica was contaminated as early as 1880 by lead that could be traced back to the metallurgical industry in South America, South Africa and Australia. Another source may have been steamships. Lead levels then sank in the 1920s, and it has been speculated that this was related to the opening of the Panama Canal in 1914, which resulted in less shipping. Lead contamination then increased significantly during the Second World War (1939-1945) due to more activity in the metallurgical industry and a high lead content in petrol. The analyses of the snow samples have shown a reduction from the 1980s to the present day, probably because of the introduction of lead-free fuel.

A study of a number of organic pollutants (HCB, heptachlor, HCH, derives from heptachlor, an insecticide.” data-hasqtip=”8″>heptachlor epoxide) in air, seawater, sea ice and snow from the Antarctic Peninsula has shown that the levels of several of the substances have declined. Heptachlor epoxide levels, however, have not dropped during the past decade, suggesting that heptachlor is still being used in the Southern Hemisphere. It was used a great deal to combat termites in the 1960s and ‘70s. The USA banned its use in 1988.