Urinary 1-hydroxypyrene as a comprehensive carcinogenic biomarker of exposure to polycyclic aromatic hydrocarbons: a cross-sectional study of coke oven workers in China
Purpose Polycyclic aromatic hydrocarbons (PAHs) are multiple compounds that include many carcinogens. We conducted a cross-sectional study in steel plant workers in Anshan, China, to identify biomarkers that reflect the carcinogenicity of PAHs.
Methods Subjects were 57 workers and 20 controls. Level of personal exposure to PAHs was measured using GC–MS. In accordance with the assessment methods defined by the United States Environmental Protection Agency (US EPA), 15 PAHs were selected for the analysis. For the measurement of urinary metabolites, urine samples were treated with β-glucuronidase and analyzed using HPLC with a fluorescence detector.
Results The mean range of personal exposure to 15 PAHs (total PAHs) was 178.85, 47.08–1,329.45 (geometric mean, 5th and 95th percentile) μg/m3. Ten known urinary metabolites (1-hydroxynaphthalene, 2-hydroxynaphthalene, 2-hydroxyfluorene, 1-hydroxyphenanthrene, 3-hydroxyphenanthrene, 9-hydroxyphenanthrene, 1-hydroxypyrene, 3-hydroxybenz[a]anthracene, 6-hydroxychrysene, and 3-hydroxybenzo[a]pyrene) and four unknown peaks were detected. The highest correlation was between total PAHs and urinary 2-hydroxynaphthalene (Spearman r = 0.716, P < 0.01). Among the detected urinary metabolites, 2-hydroxyfluorene, 1-hydroxyphenanthrene, 3-hydroxyphenanthrene, and 1-hydroxypyrene were found to correlate significantly with the “Σ carcinogenic potency of PAHs” (sum of seven carcinogenic PAHs calculated from the levels of personal PAHs and relative potency factors), and with the greatest correlation found for 1-hydroxypyrene (Spearman r = 0.630, P < 0.01).
Conclusions The analysis of personal exposure to 15 PAHs and 10 urinary metabolites, and calculation of Σ carcinogenic potency, indicated that urinary 1-hydroxypyrene was the most comprehensive carcinogenic biomarker of exposure to PAHs.