Study of Expression Correlation between Levels of DNA Adducts and Occupational Exposure to Vinyl Chloride

Objectives To assess the DNA damage of occupational population exposed to vinyl chloride.

Methods The exposure group consisted workers from the vinyl chloride plant. The control group consisted administration management and service personnel. A 4 mL whole blood of venous blood sample was obtained from each participant. An ultra-performance liquid chromatography tandem mass spectrometry was used to detect two kinds of DNA adducts, εdA and εdC, in blood samples of participants. One-way ANOVA and Multi-way ANOVA were used to analyze the effect of gender, age, drinking, smoking, and vinyl chloride exposure on εdA and εdC content in blood.

Results The contents of εdA and εdC in blood sample of exposure group were (3.38±2.58) pmol/mg and (2.37±1.84) pmol/mg, respectively. The contents of εdA and εdC in blood sample of control group were (1.39±1.20) pmol/mg and (0.83±0.73) pmol/mg, respectively. The levels of εdA and εdC in the exposure group were higher than the levels in the control group with significant differences (P < 0.05). There was no significant difference in the effects of age, smoking, and drinking on the content of εdA in blood sample of participants (P > 0.05). Similarly, there was no significant difference in the effects of age and smoking on the content of εdC in the blood sample of participants (P > 0.05). The level of εdC in blood sample of drinkers was higher than that of non-drinkers with significant differences (P < 0.05).

Conclusions Even if the level of occupational exposure to vinyl chloride is lower than the occupational exposure limit (PC-TWA=10 mg/m³), the level of εdA and εdC in the blood of exposure group was significantly higher than that of the control group. The low level of vinyl chloride exposure can also cause the increase of DNA adducts, resulting in DNA damage, and increasing the cancer risk to contact person.