Marine Arctic
Contamination
- Though still considered pristine in comparison with
most other parts of the world, the Arctic is being
significantly contaminated by pollutants discharged from
urban, agricultural and industrial regions to the south.
They have been detected in Arctic air, fog, water, and
snow, with substantial accumulations in marine mammals,
various seabird and terrestrial animal species — and
humans.
- For example, potentially harmful PCB levels have been
found in sea otters and bald eagles in the Aleutian
Islands, one of the most remote areas of North America.
PCB levels in various seabird species from the Canadian
and Norwegian Arctic approach or exceed levels associated
with reproductive effects in laboratory birds. Some of
the highest amounts of contamination have been found in
polar bears leading researchers to speculate that recent
cases of abnormal genitalia discovered in animals from
Svalbard (in the northern Barents Sea) may result from
endocrine disruption caused by environmental
pollution.
- The contamination of Arctic wildlife has resulted in
extremely high pollutant levels in some native human
populations. Infants receive significant loadings via
breast milk and, in some northern regions, children have
levels of various industrial chemicals as much as 10
times higher than in those children living in the more
southerly industrialized regions. Levels in adults can be
as much as 20 times higher than their counterparts to the
south. The main human health concerns center around
effects on neurological development, the reproductive and
immune systems, and cancer development and promotion.
- It is expected that high levels of certain
contaminants in the Arctic environment will persist for
decades despite recent reductions in global emissions.
Threats are potentially posed by the production and use
of "new generation" pesticides and industrial chemicals
and by increases in pollution emissions from industrial
development within the Arctic itself and the developing
regions outside the Arctic, such as China.
- Chemical groups of current concern in the Arctic
include:
- The persistent organic pollutants (also called
POPs) including industrial chemicals (e.g., the PCBs,
brominated flame retardants), byproducts of industrial
processes (e.g., dioxins and furans,
hexachlorobenzene), and pesticides (e.g., DDT,
chlordane, atrazine);
- The heavy metals, especially cadmium and mercury,
both of which are released by such sources as
fossil fuel combustion, waste incineration, and in
various mining and metallurgical processes;
- The radionuclides (e.g., strontium-90, plutonium)
primarily from past atmospheric testing of nuclear
weapons, the Chernobyl disaster and other accidents,
releases from nuclear fuel reprocessing plants in
Europe, and the dumping and storage of nuclear
waste;
- The petroleum hydrocarbons either originating from
within the Arctic as a result of spills and discharges
from shipping, pipelines, oil and gas drilling and
production operations, or transported to the Arctic
via the atmosphere.
- There are various pathways by which environmental
pollutants end up in the Arctic. Primary among them is
atmospheric and ocean transport from the industrialized
and agricultural regions in the lower latitudes. This
transfer can occur rapidly -- from days to weeks in the
case of aerosols and minute particles. Volatile and
semi-volatile compounds, however, move as gases over many
years. In this process, chemicals volatilize in warm
temperatures and condense onto land and water when
temperatures drop. This dynamic continues as thc
contaminant gradually moves northward with prevailing
wind and current patterns until it reaches the colder
Arctic "sink". Knowledge of this process has prompted
concern that for many persistent chemicals a large
portion of their total global production may be still
working its way northward.
- Contaminants are also transported from more southern
regions by Arctic rivers. In addition, there are numerous
pollution sources from within the Arctic including oil
and gas installations, mining and metallurgy industries
and, notably in northwestern Russia, nuclear waste dumps
and storage sites.
- Much is still not known about the sources, levels and
trends, wildlife and human health effects, and possible
future scenarios of pollution in the Arctic. However,
much research is being supported by various governments
in order to reduce gaps in current understanding.
- Great concern surrounds the known and suspected
effects of contaminants ingested from wildlife diets and
breast milk. However, because of the benefits of
traditional foods and breast feeding, health care
professionals typically recommend that they not be
abandoned. It is being increasingly recognized that there
is a need for dietary advice to Arctic peoples so they
can make informed choices concerning the foods they
eat.
- The Arctic Monitoring and Assessment Programme
(AMAP), established by the eight Arctic countries (US.,
Canada, Iceland, Denmark, Norway, Sweden, Finland, and
Russia) of the Arctic Environmental Protection Strategy
-- and incorporated into the newly formed Arctic Council
-- has made numerous recommendations on reducing Arctic
contamination. For example, they suggest that:
- Strong support should be given for an
international, legally-binding global agreement on
PCPs, for which negotiations have begun;
- There should be an expeditious completion of
protocols on POPs, nitrogen, cadmium, mercury, and
lead under the auspices of the Convention on
Long-range Transboundary Air Pollution;
- Strong support should be given to other
international agreements such as the international
conventions on ocean dumping (LC72) and marine
pollution from ships (MARPOL), both of which aim to
reduce releases of POPs, heavy metals, and
hydrocarbons to the environment.
Arctic Monitoring and Assessment Programme. 1997.
The AMAP Assessment Report: Arctic Pollution Issues.
AMAP: Oslo, Norway.
Ayotte, P. et al. 1995. Arctic air pollution and human
health: what effects should be expected? The Science
of the Total Environment
160/161: 529-537.
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