FATE OF MERCURY IN THE ARCTIC Michael Evan ... - COGCI

Fate of Mercury in the Arctic 11
analyses from. In the Arctic, these cores are taken from areas where AMDEs do not occur, typically
at altitudes greater than 2 km above sea level on the inland ice. AMDEs are coastal phenomenon, so
it was necessary to find a suitable environmental archive to investigate background and recent
levels of mercury in the Arctic. For this work, peat was chosen, since there are many unanswered
issues regarding Hg diagenesis in aquatic environments and sedimentation rates in Arctic limnic
systems are very slow.
In general, the state of Hg research is relatively immature, compared with other trace metals,
especially lead. The global and Arctic Hg cycle is poorly understood, and source receptor
relationships need to be well formulated in order to apply the science to real world problems. The
most actual present day large-scale mercury problem is faced in the Arctic, i.e., where ecosystems
and local communities are fragile due to high exposure. Mercury’s toxicity has already had
measurable effects in the Faroe Islands (Grandjean et al., 1992, 1995, 1997; Sørensen et al., 1999;
Steuerwald et al., 2000). In 1986 in north Greenland more than 80% of the population exceeded the
benchmark level of concern for the United States, 50 µg Hg l -1 blood and 16% exceeded the World
Health Organization, WHO, minimum toxic blood concentration in non-pregnant adults, 200 µg Hg
l -1 blood (Hansen and Pedersen, 1986). Weihe et al., 2002 suggest, but do not conclude, that
observed neurobehavioral deficits in Inuit children from Qaanaqq, NW Greenland might be related
to dietary mercury exposure.
Therefore, the National Environmental Research Institute in co-ordination with the University
of Copenhagen Global Change Initiative, COGCI, initiated Arctic mercury monitoring and research
programmes, commencing shortly after the Canadian discovery. This Ph.D. is a part of these
national efforts, and is focused on the atmospheric chemistry of mercury, its gaseous deposition and
subsequent and historical accumulation in the Arctic.