World industry
poisons Arctic purity
for the Independent (London)
December 15, 1996
A Climatic Trick Dumps Chemicals from afar on people and animals in the
far north, writes Geoffrey Lean.
Their language may have 30 different words for "snow" but it
doesn't have one for "contamination". So it is hard to explain
to the Inuit people of the remote and pristine Broughton Island in the Canadian
Arctic that - thanks to a strange and newly discovered trick of natural
systems - they are more polluted by some of the world's most toxic chemicals
than any other people on earth.
And yet research shows that the bodies of the 450 people of the small
island, thousands of miles awy from the source of the pollution have the
highest levels of polychlorinated biphenyls (PCBs) ever found, except in
victims of industrial accidents. The chemicals are increasingly suspected
of causing cancer, suppressing fertility and damaging the immune system.
Neighbouring peoples, on the vast Baffin Island next door, shun them
as "PCB people" and try to dissuade their children from marrying
them. But the neighbours are highly contaminated too: Inuit from Greenland
on one side of Baffin and Broughton Islands to Arctic Quebec on the other,
have seven times as much of the chemicals in their bodies as people living
in temperate and industrialised parts of Canada.
PCBs were long ago banned in most industrial countries after being used
in a host of applications from paints to pesticides, plastics to electrical
equipment - but they are still concentrating in the Artic. Curiously, they
are doing so as the direct result of their continued use in developing countries
in the tropics.
It is a similar story for a host of similarly dangerous chemicals. Measurements
quoted by the authoritative technical magazine, Environmental Data Services,
show that Greenlanders have more than 70 times as much of the pesticide
hexachlorobenzene (HCB) in their bodies than temperate Canadians. Another
pesticide HCH is over 100 times more concentrated in the waters of the Arctic
Beaufort Sea than in the Java Sea, near where it is mainly used.
Polar Bears, seals, fish and birds of prey are also heavily polluted,
and Arctic ecosystems are under threat. DR Frank Wania of the Norweigan
Institute of Air Research at Tromso, 200 miles north of the Arctic Circle,
says: "The circumpolar nations should be very concerned". Dr Wania
who first stumbled across the growing crisis at the beginning of the decade
when studying for his doctorate - and other scientists believe that the
cause is "global distillation", which picks up pollutants from
where they are released and dumps them, many thousands of miles away, on
some of the most fragile ecosystem and vulnerable peoples in the world.
The alarming planetary phenomenon is turning the roof of the earth into
its ultimate chemical dump.
In the process, the world seems to act as a giant distillery, Volatile
chemicals - such as PCBs, HCBs, dioxins and other pesticides such as toxaphene
and DDT - boil off into the air when they are used in the tropics. The chemicals
are then carried by the winds until they hit cooler climates, where they
condense and fall to earth.
As in the fractionated distillation equipment used in school science
classes, different groups of chemicals condense at different temperatures.
DDT for example is less volatile than many others and, seems to be deposited
mainly in temperate regions. So is toxaphene: high levels of the pesticide
are found in North Sea fish, even though it has rarely been used in Europe.
HCB, HCH and some forms of PCBs - which are much more volatile - seem
to carry on all the way up to the Arctic: concentrations in seals, for example,
increase the further north you go. An estimated 99.9% of the HCH used on
rice paddies in South India boil off into the atmosphere to condense out
elsewhere. And research shows that concentrations of HCBs are negligible
in the tropics, where they are mainly used, except in the high African mountains,
where the temperature drops enough for condensation to occur.
Dr Wania SAYS that the chemicals can take between a few weeks and decades
to find their way north. At one extreme a favourable wind can carry them
straight up from the tropics in just a fortnight. At the other, they may
move northwards in a series of small jumps that he calls "the grasshopper
effect" repeatedly condensing out and then evaporating again for the
next jump, as temperatures change with the season. "Even pesticides
sprayed in the 1950s may still be on their way" he says.
However long the journey, the Arctic is the end of the line. Less is
known about what is happening in the Antarctic, because far fewer measurements
have been done, but Dr Wania thinks there is less global distillation there.
The chamicals are mostly used in the northern hemisphere, he says, and winds
and the pollution they carry tend not to cross the equator. There also seems
to be less movement of air towards the Pole in the southern hemisphere.
The chemicals concentrate in the Arctic because it is a relatively small
area, attracting pollution from the whole hemisphere. Other special features
also increase the danger - the cold slows down the natural decomposition
of the chemicals, and Arctic wildlife relies on thick layers of blubber
and fat, in which pollution builds up. The Inuit are at the top of the food
chain eating a lot of local fish and wildlife. So although they have contributed
virtually nothing to the pollution, and do not benefit at all from the use
of the chamicals thousands of miles to the south, they are becoming its
principal victims.
Dr Wania believes that the use of these chemicals will have to be banned
worldwide, because of what is happening in the Arctic. The United Nations
Environment Programme is beginning work on a draft international treaty
which could achieve this, but the pollution of many years is already in
the planet's atmosphere, working its way towards the poles. |
