Abstract
The 11 September 1998 issue of Science included an article, "History of Atmospheric Lead Deposition Since 12,370 14C yr BP from a Peat Bog, Jura Mountains, Switzerland" (pp.1635-40, summarized on pp. 1622-3). This article reports the findings from the study of lead (Pb) and scandium (Sc) concentrations in a core from a Swiss peat bog. The lead concentrations were found to vary greatly over the length of the core and, based on previous studies,1 are attributable to the effects of atmospheric lead deposition alone. Interestingly, lead concentrations from a depth of 145 cm, dated at 3000 14C yr BP, to the top of the 650 cm core can be easily correlated with the record of lead production over the past 3000 years. At the 145 cm mark, the 206Pb/207Pb ratio begins to decrease and the amount of Pb relative to Sc no longer remains in the same proportions. This is indicative of the advent of mining and the subsequent release of lead into the atmosphere. Prior to this time, ratios of radiogenic lead and Pb/Sc match those from exposed soils from Europe and Northern Africa. Above 145 cm, changes in deposition rates and 206Pb/207Pb ratios follow patterns of the use of lead throughout history including the rise and fall of the Roman Empire, the medieval silver production in Germany, the Industrial Revolution, and, finally, to its highest levels with the introduction of gasoline containing lead.