Abstract
We have studied oxidative DNA damage using 7,8-dihydro-8-oxodeoxyguanosine (8-oxodG) and thymine glycol (TG) as biomarkers for occupational exposure to diesel exhaust. DNA was extracted from lymphocyte of 19 exposed bus garage and waste collection workers, and 18 controls. The measurement of 8-oxodG was carried out by HPLC with an EC detector. High individual variations between 8-oxodG levels were observed, however, the mean 8-oxodG obtained from the exposed workers was not statistically different from the control persons. Thymine glycol (TG) in urine of exposed and control persons was analyzed with TG-d4 as an internal standard. Five ml of urine was treated with the affinity column and C18 cartridges, then HPLC separations were processed. The fractions containing endogenous TG and the deuterated internal standard were derivatized with BSTFA. The GC/MS analysis was performed by JMS-700 with the high resolution SIM mode. The TG levels in human urine were low and the purification procedure of urine samples needs to be further developed. [J Radiat Res 44:437 (2003)]
