Urinary polycyclic aromatic hydrocarbons and monohydroxy metabolites as biomarkers of exposure in coke oven workers.

OBJECTIVES: To assess exposure to polycyclic aromatic hydrocarbons (PAHs) using 13 unmetabolised PAHs (U-PAHs) and 12 monohydroxy metabolites (OHPAHs) in urine, and to compare the utility of these biomarkers. METHODS: 55 male Polish coke oven workers collected urine spot samples after a workshift. U-PAHs (naphthalene, acenaphtylene, acenaphthene, fluorene, phenanthrene, anthracene, fluoranthene, pyrene, benzo[a]anthracene, chrysene, benzo[k]fluoranthene, benzo[b]fluoranthene, benzo[a]pyrene) were determined by automatic solid phase micro-extraction followed by gas chromatography/mass spectrometry (GC/MS). OHPAHs (1- and 2-hydroxynaphthalene, 2- and 9-hydroxyfluorene, 4-, 9-, 3-, 1- and 2-hydroxyphenanthrene, 1-hydroxypyrene, 6-hydroxychrysene, 3-hydroxybenzo[a]pyrene) were determined, after liquid/liquid extraction and derivatisation, by GC/MS. RESULTS: U-PAHs from naphthalene to chrysene were found in 100% of samples, and heavier U-PAHs in 7-22% of samples. OHPAHs up to 1-hydroxypyrene were found in 100% of samples, while 6-hydroxychrysene and 3-hydroxybenzo[a]pyrene were always below the quantification limit. Median naphthalene, phenanthrene, pyrene, chrysene and benzo[a]anthracene levels were 0.806, 0.721, 0.020, 0.032 and 0.035 microg/l, while hydroxynaphthalenes, hydroxyphenanthrenes and 1-hydroxypyrene levels were 81.1, 18.9 and 15.4 microg/l. For each chemical, the ratio between U-PAH and the corresponding OHPAH ranged from 1:26 to 1:1000. Significant correlations between logged values of U-PAHs and OHPAHs, between U-PAHs, and between OHPAHs were found, with Pearson's r ranging from 0.27 to 0.97. CONCLUSION: Current analytical techniques allow specific and simultaneous measurement of several urinary determinants of PAHs in humans. The results of these measurements support the use of U-PAHs as biomarkers of exposure and suggest the spectrum of chemicals to be investigated, including carcinogenic chrysene and benzo[a]anthracene, should be widened.

Association between urinary 1-hydroxypyrene and genotoxic effects in coke oven workers.

AIMS: To investigate whether current occupational exposure of coke oven workers to polycyclic aromatic hydrocarbons (PAHs) results in genotoxic effects measured in peripheral blood lymphocytes and whether these biomarkers are associated with the biomarkers of exposure. METHODS: Blood and urine samples were collected immediately after a shift at the end of a working week from 50 coke oven workers and 50 control workers not exposed to PAHs. Methods included: (1) biomarkers of exposure: urinary 1-hydroxypyrene (HpU), urinary mutagenicity by the plate Salmonella test with strains TA98 and YG1024 after metabolic activation, expressed as mutagenic rate (MR98 and MR1024, respectively), urinary cotinine; and (2) biomarkers of biological effects in peripheral blood lymphocytes (PBL): sister chromatid exchanges (SCE/cell), cells of high frequency of SCE (% HFC), micronuclei (MN/1000 cells), chromosomal aberrations (CA/100 cells), and DNA damage by the Comet assay. RESULTS: Occupational exposure to PAH resulted in significantly increased levels of HpU and mutagenic effect of urine. Median values of these biomarkers in coke oven workers were: 9.0 micromol/mol creatinine for HpU, 2.7 for MR98, and 8.2 for MR1024, compared to the controls: HpU = 0.6 micromol/mol creatinine, MR98 = 1.2, and MR1024 = 5.5. Occupational exposure caused significant induction of SCE, HFC, and MN in coke oven workers: median SCE = 5.9, HFC = 12.0%, MN = 6.0 compared to the controls: 3.9, 5.0%, and 3.0, respectively. No effect of occupational exposure was found in relation to CA and DNA damage measured with the Comet assay. HpU concentration was positively associated with SCE and HFC. The concentration of urinary 1-hydroxypyrene corresponding to a 5% probability of increased SCE was 1.0 micromol/mol creatinine. CONCLUSIONS: The occupational exposure to PAHs resulted in measurable biological effects (SCE, HFC, MN). In coke oven workers an increased level of SCE was not observed below the level of 1.0 micromol HpU/mol creatinine.