Förderkennzeichen: DFG SPP 1315
Compound specific isotope analysis (CSIA) can be used to investigate and monitor the fate of organic contaminants in groundwater and soil systems. CSIA measures the isotope composition of a compound at natural abundance. The ratio of the isotopes (13C/12C, 2H/1H, 15N/14N, 18O/16O) is given relative to the international standard (Peedee Belemnite for carbon). On the one hand, different isotopic compositions of the same chemical substance can be used as fingerprints to determine the source of contamination. On the other hand, it may serve to verify that biological degradation occurs. It is well established that during chemical reactions and biodegradation, the heavier isotopes become enriched within the remaining substrate and the light isotope becomes enriched on the site of the products.
But it is not well established to what extend sorption of pesticides at soil components leads to similar isotope fractionation in the pesticides. CSIA as a tool to verify biodegradation might also serve as tool to investigate natural reactions as well as sorption associated with isotope fractionation.