Comment on "The biosphere: A homogeniser of Pb-isotope signals" by C. Reimann, B. Flem, A. Arnoldussen, P. Englmaier, T.E. Finne, F. Koller and Ø. Nordgulen
2008 (English)In: Applied Geochemistry, Vol. 23, no 8, 2519-2526 p.Article in journal (Refereed) Published
The paper by Reimann et al. (2008) is an echo of the debate carried out mainly by Clair Patterson and Robert Kehoe in the 1960s to 1980s about whether the enrichment of Pb in the biosphere and humans was a result of the global Pb contamination or due to natural causes and what impacts on human health were entailed ([Needleman, 1998] and [Nriagu, 1998]). Reimann et al. are also re-awakening the idea that the ‘plant pump’ is the reason for the surface enrichment of Pb in the soil (Goldschmidt, 1937). So is it time to revive this debate again? Are there reasons to expect that the enrichment of Pb and the change in Pb isotopic composition in surface soils is due to natural plant cycling and not due to the 1000-fold enrichment of Pb in the environment and humans since pristine times as originally suggested by Clair Patterson ([Patterson, 1965] and Settle and Patterson, 1980 D. Settle and C.C. Patterson, Lead in Albacore: guide to lead pollution in Americans, Science 207 (1980), pp. 1167–1176. View Record in Scopus | Cited By in Scopus (97)[Settle and Patterson, 1980])? Is it so that a changed plant uptake can explain the >90% reduction of Pb in mosses seen all over Europe since the 1970s, which co-occurs with reduced atmospheric emissions (e.g., [Berg and Steinnes, 1997a] and [Rühling and Tyler, 2001])? Is there a reason to believe that plants, independent of the geological matrix below choose to take up Pb with an isotopic composition that causes the surface organic layer all over Europe to have lower (i.e., heavier) 206Pb/207Pb ratios that are coincidentally similar to anthropogenic Pb sources? No, of course not. In this comment the author explains why he thinks future studies should not adopt the conclusions of Reimann et al.
Place, publisher, year, edition, pages
2008. Vol. 23, no 8, 2519-2526 p.
IdentifiersURN: urn:nbn:se:umu:diva-11346DOI: doi:10.1016/j.apgeochem.2008.05.004OAI: oai:DiVA.org:umu-11346DiVA: diva2:151017