Association between environmental exposure to benzene and oxidative damage to nucleic acids in children.
OBJECTIVE
To evaluate the association between environmental exposure to benzene and oxidative damage to nucleic acids in children, also considering the role of Environmental Tobacco Smoke (ETS).


METHODS
396 children living in central Italy were recruited in districts with different urbanization and air pollution. All biomarkers were determined in spot urine samples by mass spectrometric techniques to assess exposure [benzene (U-Benz), and its metabolites (t,t-muconic and S-phenylmercapturic acids, t,t-MA and S-PMA, respectively), cotinine] and nucleic acid oxidation [8-oxo-7, 8-dibydro-2'-deoxyguanosine (8-oxodGuo), 8-oxo-7, 8-dihydroguanosine (8-oxoGuo), and 8-oxo-7, 8-dihydroguanine (8-oxoGua)].


RESULTS
Biomarkers of exposure and nucleic acid oxidation increased with urbanization and were correlated with each other (r > 0.18, p < 0.005). In a multiple linear regression model, benzene exposure, assessed by S-PMA and t,t-MA, was associated (p < 0.0001) with both 8-oxodGuo (R2 = 0.392) and 8-oxoGuo (R2 = 0.193) in all areas of residence, with similar slopes.


CONCLUSIONS
(i) Biomarkers of exposure to benzene increased as a function of environmental air pollution and urbanization level; (ii) U-Benz clearly distinguished both exposure to ETS and areas of residence, whereas benzene metabolites were associated only with the latter; (iii) the variance of 8-oxodGuo and 8-oxoGuo was accounted for by environmental benzene exposure, thus suggesting that benzene is a good tracer of other components of complex mixtures of pollutants causing oxidative damage to nucleic acids.
Laboratory of Industrial Toxicology, Department of Clinical Medicine, Nephrology and Health Sciences, University of Parma, Parma, Italy. roberta.andreoli@unipr.it
Roberta
R
Andreoli
Carmela
C
Protano
Paola
P
Manini
G
G
De Palma
M
M
Goldoni
Marta
M
Petyx
Bruna Maria
BM
Rondinone
M
M
Vitali
A
A
Mutti
D000080242:8-Hydroxy-2'-Deoxyguanosine; D000111:Acetylcysteine / Q000031:analogs & derivatives / Q000652:urine; D000393:Air Pollutants / Q000633:toxicity*; D001554:Benzene / Q000493:pharmacokinetics / Q000633:toxicity*; D015415:Biomarkers; D002648:Child; D003367:Cotinine / Q000652:urine; D004247:DNA / Q000187:drug effects*; D004249:DNA Damage; D003849:Deoxyguanosine / Q000031:analogs & derivatives / Q000652:urine; D004784:Environmental Monitoring; D005260:Female; D006147:Guanine / Q000031:analogs & derivatives / Q000652:urine; D006151:Guanosine / Q000031:analogs & derivatives / Q000652:urine; D006801:Humans; D007558:Italy / Q000453:epidemiology; D008297:Male; D018384:Oxidative Stress; D012313:RNA / Q000187:drug effects*; D012424:Rural Population; D013011:Sorbic Acid / Q000031:analogs & derivatives / Q000032:analysis; D013383:Suburban Population; D014028:Tobacco Smoke Pollution / Q000009:adverse effects*; D014505:Urban Population
D000393:Air Pollutants; D015415:Biomarkers; D014028:Tobacco Smoke Pollution; D006151:Guanosine; C046215:8-hydroxyguanosine; C005939:muconic acid; C053003:S-phenyl-N-acetylcysteine; C024829:8-hydroxyguanine; D006147:Guanine; D012313:RNA; D000080242:8-Hydroxy-2'-Deoxyguanosine; D004247:DNA; D003849:Deoxyguanosine; D001554:Benzene; D003367:Cotinine; D000111:Acetylcysteine; D013011:Sorbic Acid