Polar and alpine environments - Fundamentals of the Physical Environment - page 628

Biomagnification

Murre

Polar Bear

Inuit

x 5

x 8

Ringed seal

Beluga

x 8

Arctic Cod

x 25

x 8

x 25

Zooplankton

x 2 million

Sea water

Arctic cod

Figure 24.22 Biomagnification of PCB pollutants in the Arctic marine food web. Amount of biomagnification (multiplication) is
indicated at each link in the web.

Table 24.3 Contaminants from distant sources in polar regions

Chlorinated organics Industrial chemicals PCBs, HCBs, dioxins, furans

Agricultural pesticides HCH, DDT, DDE,
chlordane, toxaphene, organophosphorus

Heavy metals Mercury, cadmium, lead, arsenic, selenium

Radionuclides Strontium-90, caesium-137, plutonium-239

Acid precipitation Oxides of sulphur and nitrogen

milk of the herds are very vulnerable. An additional
threat has come from the decommissioning, storage and
disposal of nuclear reactors from former Soviet nuclear
submarines at towns such as Murmansk and Archangel
on the coast of the Barents Sea. The tragic loss of two
Russian nuclear submarines in the Barents Sea, the
Konsomolts in 1989 and the Kursk in 2000, both with
nuclear reactors and nuclear warheads, leaves another
deadly legacy on the sea bed.

Acid precipitation charged with sulphur and nitrogen
oxides is a long-range pollution problem. Although
sulphate deposition from acid deposition is less than 3 kg
ha -1 yr -1 and acid levels are ten times lower than in
temperate industrial areas, a continuous acid load can
lower biological productivity in freshwater lakes, with the
gradual release of heavy metals, which are more soluble
in acid conditions. About 95 per cent of the input of
sulphur into Arctic regions arrives during the winter