Antimony in recent, ombrotrophic peat from Switzerland and Scotland:: Comparison with natural background values (5,320 to 8,020 14C yr BP) and implications for the global atmospheric Sb cycle -: art. no. GB1016

[1] The lowest concentrations, atmospheric fluxes, and enrichments of Sb in a Swiss bog were found in peat samples dating from 8,020 to 5,320 C-14 yr BP when Sb inputs were proportional to those of Sc and effectively controlled by deposition of soil dust. For comparison with these ancient samples, modern peat samples from five rural areas of Switzerland and two remote areas of Scotland and Shetland are highly contaminated with Sb, with enrichments of the order of 30 to 80 times. "Lithogenic'' Sb concentrations calculated using the Sc concentrations and background Sb/Sc ratio are dwarfed at all sites by "anthropogenic'' Sb. The chronology and intensity of the Sb enrichments are in many ways similar to those of Pb which indicates that ( 1) Sb, like Pb, is well preserved in ombrotrophic peat and ( 2) the extent of human impacts on the geochemical cycle of Sb is comparable to that of Pb. The similar distribution of Sb and Pb can be explained in terms of their chemical and mineralogical associations, with most lead minerals being rich in Sb. Assuming that the "background'' Sb flux (0.35 mug/m(2)/yr) from the Swiss bog is representative of preanthropogenic deposition rates worldwide, the global flux of natural Sb is estimated at 154 T/a. Using the natural Pb flux published by Patterson and Settle [ 1987] of 2600 T/a and the "background'' Pb/Sb ratio ( 29) of the preanthropogenic peat samples, the global flux of natural Sb is estimated at 90 T/a. Either way, these values ( 90 to 154 T/a) are considerably lower than the current estimate of natural Sb to the global atmosphere ( 2400 T/a) published by Pacyna and Pacyna [ 2001]. Assuming that the current estimate of anthropogenic Sb to the global atmosphere ( 1600 T/a) is correct [ Pacyna and Pacyna, 2001], the ratio of anthropogenic to natural Sb emissions is on the order of 10 to 18. Taken together, the data from modern and ancient peat samples suggests that the impact of human activities on the global geochemical cycle of Sb may have been underestimated by an order of magnitude. Like Pb, Sb has no known biological function, has a similar toxicity, and is a cumulative poison. The environmental geochemistry of Sb therefore may have a relevance to human and environmental health comparable to that of Pb.