[Study on repair capacity of DNA damage associated with chronic benzene poisoning].
OBJECTIVE
To explore the repair capacity of DNA damage associated with chronic benzene poisonings.


METHODS
63 workers suffered from chronic benzene poisonings and 45 workers exposed to benzene, who were engaged in the same job title, were investigated. Comet assay and cytokinesis-block micronucleus (CBMN) detection were used to evaluate gamma-radiation-induced DNA and chromosomal damage and repair capacity in peripheral blood lymphocyte.


RESULTS
The comet tail length difference of the benzene poisoning group (4.64 +/- 1.57 microm) was significantly higher than that of the control group (3.77 +/- 1.30 microm) (P = 0.0029). There was no significant difference of the 3AB index between the poisoning group and the control group. The relative risk of benzene poisoning in the subject with comet tail length difference > 3.81 was significantly higher than that in the subject with comet tail length difference < or = 3.81 microm (OR = 2.490, 95% CI:1.068 - 5.806, P = 0.0346). The relative risk increased along with the comet tail length difference, and the trend was significant (P = 0.0024). There was no significant difference between the relative risk of benzene poisoning in the subject with 3AB index < 0.20 and that in the subject with 3AB index > or = 0.20.


CONCLUSIONS
DNA repair capacity on DNA-strand level might tightly associate with chronic benzene poisoning. The DNA repair capacity on DNA-strand level would be worse, and the benzene poisoning risk could be higher. There was no clear relation between the DNA repair capacity on chromosome level and the benzene poisoning risk.
Xing
Cai-hong
CH
Institute of Occupational Health and Poison Control, Chinese Center for Disease Control and Prevention, Beijing 100050, China.
Ji
Zhi-ying
ZY
Li
Gui-lan
GL
Yin
Song-nian
SN
D000328:Adult; D001554:Benzene / Q000506:poisoning*; D002908:Chronic Disease; D020552:Comet Assay; D048749:Cytokinesis; D004249:DNA Damage; D004260:DNA Repair; D005260:Female; D006801:Humans; D008214:Lymphocytes / Q000378:metabolism; D008297:Male; D015162:Micronucleus Tests / Q000379:methods; D016273:Occupational Exposure / Q000009:adverse effects*; D011041:Poisoning / Q000097:blood / Q000235:genetics
D001554:Benzene