The delta2H- and delta13C-values of polyhalogenated compounds were determined by EA-IRMS. Most of the compounds were related to the chloropesticides DDT and its metabolites, hexachlorocyclohexanes, and toxaphene, as well as several polybrominated compounds such as bromophenols and -anisoles. delta2H-values ranged between -235 per thousand and +75 per thousand whereas delta13C-values were found in the range -22 per thousand to -38 per thousand. No correlation between delta2H- and delta13C-values could be identified. Comparative analysis clarified that bromophenols and the corresponding bromoanisoles may vary in their isotopic distribution. 2H NMR was used to quantify abundances of 2H isotopomers. Quantification of isotopomers of 2,4-dibromophenol and 2,4-dibromoanisole proved that both compounds from different suppliers do not originate from the same source. Differences in the delta2H-values of two toxaphene products were further investigated by the synthesis of products of different degree of chlorination from camphene. It was shown that the delta13C-values remained mostly unaltered as was expected since no carbon is lost in this procedure. However, the reaction products became enriched in 2H with increasing degree of chlorination. Different delta2H-values of the starting material will also impact the delta2H-values of the chlorination products.