Comment on "Lead isotopic evidence for an Australian source of aeolian dust to Antarctica at times over the last 170,000 years" by P. De Deckker, M. Norman,
A recent paper by De Deckker et al. (2010; Lead isotopic evidence for an Australian source of Aeolian dust to Antarctica at times over the last 170,000. years, Palaeogeography, Palaeoclimatology, Palaeoecology, 285(3-4), 205-223) reports radiogenic isotope data of fluvial sediment samples from the Murray Darling Basin (MDB) in southeastern Australia. Some of these display Pb-isotope ratios similar to ancient, pre-industrial pollution dust retrieved from the EPICA Dome C ice core, Antarctica. The authors proposed that this result supports a dust provenance from the Darling sub-basin of the MDB. De Deckker et al. (2010) apparently did not appreciate the extent of anthropogenic Pb contamination of their potential Australian dust sources. In addition, they also neglected to analyze many of the other important Australian dust sources. By contrast, it is demonstrated here that the surface sediments are severely polluted, that other potential dust sources from Australia also need to be considered and that it is not possible to unequivocally distinguish Australian from South American dust using Pb-isotopes alone. C 2010 Elsevier B.V.