Investigation of atrazine metabolism in river sediment by high-performanceliquid chromatography/mass spectrometry

Microbial degradation processes play an important role in chemical water cl earance taking place in river sediments. Bacteria remove not only easily de gradable organic species, but various xenobiotics as well, producing clear and xenobiotic free water for bank-filtered wells. Atrazine is a widely use d herbicide, and it is one of the most common xenobiotics present in Danube water. In this study the pathway and kinetics of atrazine metabolism of se dimental microbiota. were studied. Samples were collected from river sedime nt and from pure microbial growth cultures. An analytical scheme including sample preparation, chromatography and mass spectrometry was developed and optimised. Solid-phase extraction (SPE) was found to be satisfactory for sa mple preparation. For qualitative analysis of samples both reversed-phase a nd normal-phase high-performance liquid chromatography/mass spectrometry (H PLC/MS) methods were developed and used. Selectivity, detection limits and accuracy of the two methods were compared. Using this analytical scheme, th e full atrazine metabolism of the organism Comamonas acidovorans was explor ed. Altogether, 12 metabolites were identified from the original compound t o the urea end product. Detection limits in the range of 50 ng L-1-1 mug L- 1 were obtained for different metabolites. Copyright (C) 2001 John Wiley & Sons, Ltd.