A peat core from Lindow bog near Manchester, England, was precisely cut into 2 cm slices to provide a high-resolution reconstruction of atmospheric Pb deposition. Radiocarbon and (210)Pb age dates show that the peat core represents the period ca. 2000 BC to AD 1800. Eleven radiocarbon age dates of bulk peat samples reveal a linear age-depth relationship with an average temporal resolution of 18.5 years per cm, or 37 years per sample. Using the Pb/Ti ratio to calculate the rates of anthropogenic, atmospheric Pb deposition, the profile reveals Pb contamination first appearing in peat samples dating from ca. 900 BC which clearly pre-date Roman mining activities. Using TIMS, MC-ICP-MS, and SF-ICP-MS to measure the isotopic composition of Pb, the (208)Pb/(206)Pb and (206)Pb/(207)Pb data indicate that English ores were the predominant sources during the pre-Roman, Roman, and Medieval Periods. The study shows that detailed studies of peat profiles from ombrotrophic bogs, using appropriate preparatory and analytical methods, can provide new insight into the timing, intensity, and predominant sources of atmospheric Pb contamination, even in samples dating from ancient times.

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This paper presents geochemical data from a blanket peat located close to a Bronze Age copper mine on the northern slopes of the Ystwyth valley, Ceredigion, mid-Wales, UK. The research objective was to explore the possibility that the peat contained a geochemical record of the pollution generateD by mining activity. Four peat monoliths were extracted from the blanket peat to reconstruct the pollution history of the prehistoric mine. Three different geochemical measurement techniques were employed and four copper profiles have been reconstructed, two of which are radiocarbon-dated. The radiocarbon dates at one profile located close to the mine confirm that copper enrichment occurs in the peat during the known period of prehistoric mining. Similar enrichment of copper concentrations is shown in one adjacent profile and a profile within 30 m away. In contrast, copper was not enriched in the other radiocarbon-dated monolith, collected approximately 1.35 km to the north of the mine. Whilst other possible explanations to explain the copper concentrations are discussed, it is argued that the high copper concentrations represent evidence of localised atmospheric pollution caused by Bronze Age copper mining in the British Isles. The results of this study suggest that copper may be immobile in blanket peat and such deposits can usefully be used to reconstruct atmospheric pollution histories in former copper mining areas.