INORGANIC CONTAMINANTS IN ARCTIC ALASKAN ECOSYSTEMS - LONG-RANGE ATMOSPHERIC TRANSPORT OR LOCAL POINT SOURCES

The moss monitoring technique (Hylocomium splendens) for tracking envi ronmental concentrations of atmospheric contaminants is applied to arc tic Alaska, Median 1990-1992 concentrations of Pb, Cd, Cu, V, and Zn a re less than or equal to median 1990 concentrations in northernmost pa rts of the Nordic/European monitoring network. Extremely low Pb concen trations (median, 0.6 mu g/g) indicate that long-range atmospheric tra nsport (LRTAP) of Pb to arctic Alaskan ecosystems is neglible. However , samples taken adjacent to a local source point (the Dalton Highway) have elevated Pb, V, and Cu. Site-specific watershed studies indicate that natural within- and between-site variability does not affect the interpretation of our Alaskan data relative to the Nordic/European net work for Pb, V and Cu. Variability is greater relative to regional dat a for Cd and Zn, but neither LRTAP nor the Dalton Highway appear to be significant contributors to local concentrations of Cd and Zn. Pilot studies of blueberries and other selected wildlife forage foods indica te that concentrations in H. splendens are generally comparable to tho se in a common caribou forage lichen, but that H. splendens may undere stimate Cu and overestimate Pb, Hg, and in some cases Cd, relative to selected forage fruits. More studies of contaminants in arctic Alaskan forage foods are needed to characterize potential exposure of human a nd wildlife populations to airborne contaminants in this region.