title: A urinary metabolite of phenanthrene as a biomarker of polycyclic aromatic hydrocarbon metabolic activation in workers exposed to residual oil fly ash.
abstract: Residual oil fly ash is a chemically complex combustion product containing a significant component of potentially carcinogenic transition metals and polycyclic aromatic hydrocarbons (PAH). Various biomarkers of PAH exposure have been investigated previously, most notably 1-hydroxypyrene (1-OHP), in urine. In this study, we assessed the utility of r-1,t-2,3,c-4-tetrahydroxy-1,2,3,4-tetrahydrophenanthrene (trans, anti-PheT), a metabolite of phenanthrene, to detect occupational PAH exposure. Urine samples collected across the workweek were analyzed for 1-OHP and trans, anti-PheT in boilermakers (n = 20) exposed to residual oil fly ash. Median baseline urinary trans, anti-PheT concentrations were 0.50 microg/g creatinine in current tobacco smokers and 0.39 microg/g creatinine in nonsmokers. Median baseline urinary 1-OHP concentrations in smokers and nonsmokers were 0.31 and 0.13 microg/g creatinine, respectively. To study further the effect of smoking exposure on the urinary PAH markers, urinary cotinine was used. Although urinary trans, anti-PheT and 1-OHP concentrations were correlated (Spearman r = 0.63; P < 0.001) for all subjects, the regression coefficient between log-transformed trans, anti-PheT and log 1-OHP was statistically significant only for subjects with low levels of urinary cotinine or for nonsmokers. Each 1-unit increase in log 1-OHP was associated with a 0.77-unit increase (95% confidence interval, 0.45-1.09) in log trans, anti-PheT in subjects with low levels of urinary cotinine (P < 0.001). In these subjects, dichotomized occupational exposure status was a significant predictor of log trans, anti-PheT (P = 0.02) but not of log 1-OHP (P = 0.2). In conclusion, we found that urinary trans, anti-PheT was detected in levels comparable with 1-OHP in occupationally exposed workers, particularly nonsmokers. This study shows that urinary trans, anti-PheT may be an effective biomarker of uptake and metabolic activation of PAHs.
authors.affiliation: Occupational Health Program, Department of Environmental Health, Harvard School of Public Health, Boston, MA 02115, USA.
authors.forename: Jee Young
authors.initials: JY
authors.lastname: Kim
authors.forename: Stephen S
authors.initials: SS
authors.lastname: Hecht
authors.forename: Sutapa
authors.initials: S
authors.lastname: Mukherjee
authors.forename: Steven G
authors.initials: SG
authors.lastname: Carmella
authors.forename: Ema G
authors.initials: EG
authors.lastname: Rodrigues
authors.forename: David C
authors.initials: DC
authors.lastname: Christiani
mesh_terms: D000328:Adult; D015415:Biomarkers / Q000652:urine*; D002244:Carbon / Q000009:adverse effects*; D060729:Coal Ash; D005260:Female; D006361:Heating; D006801:Humans; D008297:Male; D008875:Middle Aged; D016273:Occupational Exposure; D052638:Particulate Matter; D010616:Phenanthrenes / Q000378:metabolism* / Q000652:urine*; D011084:Polycyclic Aromatic Hydrocarbons / Q000009:adverse effects* / Q000032:analysis; D012907:Smoking
chemical_list: D015415:Biomarkers; D060729:Coal Ash; D052638:Particulate Matter; D010616:Phenanthrenes; D011084:Polycyclic Aromatic Hydrocarbons; C502234:r-1,t-2,3,c-4-tetrahydroxy-1,2,3,4-tetrahydrophenanthrene; C031181:phenanthrene; D002244:Carbon