DETERMINATION OF HALOGEN SPECIES OF HUMIC SUBSTANCES USING HPLC ICP-MS COUPLING/

A mass spectrometric method for the determination of chlorine, bromine and iodine species of humic substances (HS) has been developed by cou pling a HPLC system with ICP-MS. Using size exclusion chromatography, the method was applied to the characterization of natural water sample s (ground water, seepage water from soil, brown water) and a sewage wa ter sample. Quantification of iodine/HS species was carried out by the on-line isotope dilution technique, which was not possible for bromin e and chlorine species because of mass spectroscopic interferences by using a quadrupole ICP-MS. Characteristic fingerprints of the halogen/ HS species, correlated with the corresponding UV chromatogram, were ob tained dependent on the different origin of HS. Biological influences were indicated when following changes of the iodine/HS species composi tion by aging. The formation of iodine/HS species from inorganic iodid e was investigated by labelling experiments with an I-129(-) spike sol ution, resulting in the finding that specific HS fractions an preferab ly iodinated.