Abstract
This study provides an overview on Tl-speciation methods developed in the last years. Most of them require transformation of a species and do not allow direct detection of the species of interest. LC-MS and IC-ICP-MS methods are optimised for direct analysis of the Tl-species Tl+ and (CH3)2Tl+ (dimethylthallium (DMT)) in freshwater on a ng L−1 level. The methods are applied in a study of water from Vicht River in Stolberg (Germany). Tl+ is shown to be at least in part derived from anthropogenic sources among which the industrial sources may be significant. The natural occurrence of DMT is proven, although this Tl-species is temporally variable in abundance and Tl+ predominates.
Acknowledgements
Dr. Hausmann (Administration City of Stolberg) is thanked for advice and giving access to sampling locations. The help of G. Günther und H. Bostelmann (retrieval of literature) and P. Zimmermann (technical support) is gratefully acknowledged.