Pathway dependent isotope fractionation in triazine degradation.

Degradation processes of the herbicide atrazine in the environment are often underestimated with common used methods. Thus, in this dissertation, a new method was developed to detect carbon and nitrogen isotope fractionation associated with biodegradation of atrazine. This work describes development and validation of compound specific isotope analysis by GC-IRMS for atrazine. Subsequently, in lab experiments carbon and nitrogen isotope fractionation patterns were detected associated with biotic hydrolysis and biotic oxidation of atrazine. According to this, results demonstrate that this alternative analytical approach provides even the possibilty to differentiate between these two degradation pathways of atrazine. Moreover, observed isotope fractionation give for the first time mechanistic insights into the enzymatic catalyzed transformation processes of atrazine. Thus this approach can be used in future as an alternative way to determine and differentiate natural degradation processes of atrazine without the need of metabolite analysis