LAUSR

Two peat cores from two bogs were used to record changes in the atmospheric Pb accumulation rate (Pb AR) in Belgium during the Roman period. The two records were compared to assess the reliability of peat cores as archives of atmospheric Pb deposition and to establish histories of atmospheric emissions from anthropogenic sources. To address these issues we analyzed Pb concentration and its isotopes, using ICP-MS, LA-ICP-MS and MC-ICP-MS in two peat sections, spanning 1000 years each. Lead concentrations in the two cores range from 0.1 to 60 μg g−1, with the maxima between 15 and 60 μg g−1. The average natural background of Pb AR varies between 0.003 and 0.07 mg m−2 yr−1 and the maximum ranges from 0.7 to 1.2 mg m−2 yr−1 between 50 BC and AD 215. The highest Pb AR exceed the pre-Roman period values by a factor of 17–80. Pb isotopic composition indicates that mining and metallurgical activities were the predominant sources of pollution during the Roman period. The Pb AR and chronologies in the Belgian peat cores are consistent with those reported for other continental archives such as lake sediments, peat and ice cores.