Estimation of K-oc values for deuterated benzene, toluene, and ethylbenzene, and application to ground water contamination studies

Sorption partition coefficients between water and organic carbon (K-OC) for deuterated benzene, toluene, and ethylbenzene have been estimated by measuring values of the octanol-water partition coefficient (K-OW) and HPLC retention factors (k'), which correlate closely to values of K-OC. Measured values of log K-OW for non-deuterated and deuterated toluene are 2.77 (+/- 0.02) and 2.78 (+/- 0.04), respectively, indicating that within experimental error, log K-OC for deuterated and non-deuterated toluene are the same. The HPLC method provides greater precision, and yields values of Delta log K-OC (= log K-OC [deuterated] -log K-OC [non-deuterated]) of -0.021 (+/- 0.001) for benzene, -0.028 (+/- 0.002) for toluene, and -0.035 (+/- 0.003) for ethylbenzene. The small values of Delta log K-OC demonstrates that deuterated compounds are excellent tracers for the hydrologic behavior of ground water contaminants. (C) 1997 Elsevier Science Ltd.