title: Reference values for blood benzene in the occupationally unexposed general population.
abstract: Blood benzene was determined by gas chromatography-mass spectrometry in 431 "normal" subjects, subdivided into 155 rural subjects and 276 urban subjects. Blood benzene (mean value 262 ng/l) was significantly lower in rural (200 ng/l) than in urban (296 ng/l) workers, as well as differing significantly between 293 non-smokers and 138 smokers (205 ng/l and 381 ng/l, respectively). Among non-smokers, values were significantly higher (307 ng/l) in 76 chemical workers. In the total study population, in 95% of cases blood benzene was less than 718 ng/l, the 95th percentile being 514 ng/l in non-smokers vs 901 ng/l in smokers and 576 ng/l in rural vs 822 ng/l in urban subjects. Within each population subgroup, the difference between non-smokers and smokers was statistically significant, except among office workers (non-smokers 234 ng/l, smokers 304 ng/l). Blood benzene (y) was directly proportional to the number of cigarettes smoked (x) (y = 201 + 12x; r = 0.44; n = 431), and inversely proportional to the interval between the last cigarette and the time at which the blood samples was taken (z) (log y = 6.167-0.0015z; r = -0.461; n = 135). The blood half-life of benzene was about 8h. The multiple correlation between blood benzene (Cb), number of cigarettes per day (x) and time since the last cigarette (z) is: Cb = 417 + 7.2x - 0.41z (n = 135; R = 0.20; P less than 0.00001).
authors.affiliation: Institute of Occupational Medicine, University of Verona, Italy.
authors.forename: F
authors.initials: F
authors.lastname: Brugnone
authors.forename: L
authors.initials: L
authors.lastname: Perbellini
authors.forename: G
authors.initials: G
authors.lastname: Maranelli
authors.forename: L
authors.initials: L
authors.lastname: Romeo
authors.forename: G
authors.initials: G
authors.lastname: Guglielmi
authors.forename: F
authors.initials: F
authors.lastname: Lombardini
mesh_terms: D000328:Adult; D000393:Air Pollutants / Q000493:pharmacokinetics*; D001554:Benzene / Q000493:pharmacokinetics*; D004784:Environmental Monitoring; D008401:Gas Chromatography-Mass Spectrometry; D006801:Humans; D016273:Occupational Exposure; D012016:Reference Values; D012424:Rural Population; D012907:Smoking / Q000009:adverse effects / Q000097:blood; D014505:Urban Population
chemical_list: D000393:Air Pollutants; D001554:Benzene