Distribution of Chlorinated Hydrocarbon Pesticides and PCBs in the ...

INTRODUCTION
The Department of Energy, Mines and Resources, through the
Polar Continental Shelf Project (PCSP) set up a camp in 1985 on
an ice-island presently off the north-west coast of Axel Heiberg
Island (near 81°N, 97"W, see Figure 1.1). The island is an
approximately 4 x 7 km .oval shaped piece of ice, 45 m thick that
was calved from an ice shelf off the north coast of Ellesmere
Island in 1983. A similar island (Fletcher's Ice Island T-3) was
occupied by American scientists from 1952 until 1974 during which
time the island drifted in the Beaufort Gyre along the north
coast of the Canadian Archipelago into the Beaufort Sea and
subsequently made two revolutions of the Canada Basin. It is
hoped that this new island will follow a similar course. The
island and camp offers a unique opportunity to carry out
scientific studies along Canada's most northerly coast over an
extended time period.
Chlorinated hydrocarbon pesticides and polychlorinated
biphenyls (PCBs) are semi-volatile, lipophilic industrial
compounds which have environmental significance because of their
stability, toxicity and tendency to concentrate in organisms.
Although produced and used principally in the mid-latitudes and
tropics, long range transport via the atmosphere (Oehm and Ottar,
1984; Barrie, 1986) as well as surface ocean currents and river
drainage has introduced these compounds into the Arctic Ocean
Basin. PCBs and chlorinated hydrocarbon pesticides have been
detected in the Arctic, although the available data base is small
and restricted primarily to atmospheric concentrations and
tissues from large mammals. The present distribution and the
mechanisms for the transfer of these compounds between various
compartments of the arctic marine environment is poorly
understood. Very little is known about rates of biological
production in offshore areas, food web linkages and most
importantly, the sensitivity of arctic organisms to these
potentially toxic compounds. It is known that productivity and
levels of organic matter (particulate and dissolved) in the