Using lead isotopes to characterise their source, lability and solubility in alluvial soils of the Trent Catchment, UK [abstract]

Fluvial environments are a major pathway for the dispersal of trace metal pollutants. A regional geochemical survey of the UK (G-BASE) revealed that alluvial soils of the Trent Catchment were enriched with Zn, Cd and Pb (Johnson et al . 2007). Sources of Pb contamination are likely to include petrol Pb, the Pb mines in the Peak district, industry and energy production. We investigated the source, lability and solubility of Pb using a range of isotope techniques in topsoils (0-15cm depth, n=27) and subsoils (35-50cm depth, n=19) taken within 10 m of the river bed (Izquierdo et al. 2012) throughout the course of the catchment of the River Trent. We measured Pb isotope ratios (206Pb/207Pb vs 208Pb/207Pb) in the whole soil, the labile Pb pool and in soil pore waters to enable us to examine the variation and proportion of Pb from different sources in each of these pools.