Estimation of reference values for urinary 1-hydroxypyrene and alpha-naphthol in Danish workers

An increase in circulating B cells and B cell activation markers in peripheral blood is associated with cigarette smoking in a male cohort in Bangladesh

In a cohort of approximately 200 Bangladeshi men, equally divided into smokers and non-smokers and equally divided by exposure to high and low levels of drinking water arsenic, we examined ex vivo a series of immune markers and immune function tests in peripheral blood mononuclear cells (PBMC). These immune parameters included PBMC cell surface markers (CSM) for B, T, monocytes, and NK cells, activated T and B cell markers, cytokine production in vitro, and analysis of CD4 subsets (Th1, Th2, Treg, and Th17 cells). We found that the effects of cigarette smoke were quite different than those associated with arsenic or polycyclic aromatic hydrocarbon (PAH)-DNA adducts. Cigarette smoking was associated with a significant increase in the number of PAH-DNA adducts as well as an increase in urinary levels of 1-hydropxypyrene (1-OHP). After correcting for arsenic exposure and PAH-DNA adducts, we found that cigarette smoking was associated with an increase in the percentage of CD19+ B cells, as well as the percentage of activated B cells (CD19+, HLA-DRbright cells) found in PBMC. These findings demonstrate activation of the immune system during chronic exposure to cigarette smoke, which is a known risk factor for autoimmune diseases.

Short-term markers of DNA damage among roofers who work with hot asphalt

BACKGROUND

Roofers are at increased risk for various malignancies and their occupational exposures to polycyclic aromatic hydrocarbons (PAHs) have been considered as important risk factors. The overall goal of this project was to investigate the usefulness of phosphorylated histone H2AX (γH2AX) as a short-term biomarker of DNA damage among roofers.

METHODS

Blood, urine, and dermal wipe samples were collected from 20 roofers who work with hot asphalt before and after 6 h of work on Monday and Thursday of the same week (4 sampling periods). Particle-bound and gas-phase PAHs were collected using personal monitors during work hours. γH2AX was quantified in peripheral lymphocytes using flow cytometry and 8-hydroxy-2-deoxyguanosine (8-OHdG) was assessed in urine using ELISA. General linear mixed models were used to evaluate associations between DNA damage and possible predictors (such as sampling period, exposure levels, work- and life-style factors). Differences in mean biomarker and DNA damage levels were tested via ANOVA contrasts.

RESULTS

Exposure measurements did not show an association with any of the urinary biomarkers or the measures of DNA damage. Naphthalene was the most abundant PAH in gas-phase, while benzo(e)pyrene was the most abundant particle-bound PAH. Post-shift levels of γH2AX and 8-OHdG were higher on both study days, when compared to pre-shift levels. Cigarette smoking was a predictor of γH2AX and urinary creatinine was a predictor of urinary 8-OHdG. Between-subject variance to total variance ratio was 35.3 % for γH2ax and 4.8 % for 8-OHdG.

CONCLUSION

γH2AX is a promising biomarker of DNA damage in occupational epidemiology studies. It has a lower within-subject variation than urinary 8-OHdG and can easily be detected in large scale groups. Future studies that explore the kinetics of H2AX phosphorylation in relation to chemical exposures may reveal the transient and persistent nature of this sensitive biomarker of early DNA damage.

Naphthalene biomarkers and relationship with hemoglobin and hematocrit in White, Black, and Hispanic adults: results from the 2003-2004 National Health and Nutrition Examination Survey

Naphthalene is an important contaminant in indoor and outdoor air. Acute overexposure can have toxic effects, resulting in hemolysis. There have been no studies evaluating the impact of environmental exposure on red blood cell indices. We examined 1- and 2-hydroxynaphthalene urinary metabolites (NAP1 and NAP2) in non-Hispanic White, non-Hispanic Black, and Mexican-American adults in the USA and their relationship with hemoglobin (Hb) and hematocrit (HCT). Using the 2003-2004 National Health and Nutrition Examination Survey data, weighted generalized linear regression analyses were used to examine the association between Hb (in grams per deciliter) and HCT (in percent) with NAP1 and NAP2 (per 100,000 ng/L). Beta coefficients ± SE are reported. NAP1 and NAP2 were highest in non-Hispanic Blacks, followed by non-Hispanic Whites, and lowest in Mexican-American adults. There was a positive association between NAP1 and Hb (0.39 ± 0.11, p = 0.0034) and HCT (1.14 ± 0.28, p = 0.0009) after adjusting for age, gender, race, education, and smoking. Stratified analysis by smoking showed similar results with the association being stronger for smokers (Hb 0.63 ± 0.23, p = 0.02; HCT 1.43 ± 0.79, p = 0.09) than nonsmokers (Hb 0.34 ± 0.14, p = 0.03; HCT 1.08 ± 0.42, p = 0.02). The association was also stronger for non-Hispanic blacks (Hb 0.54 ± 0.20, p = 0.02; HCT 1.43 ± 0.55, p = 0.02) than for non-Hispanic whites (Hb 0.37 ± 0.18, p = 0.06; HCT 1.20 ± 0.51, p = 0.03) and was not significant for Mexican-Americans (Hb 0.30 ± 1.7, p = 0.10; HCT 0.99 ± 0.52, p = 0.08). NAP2 was not significantly associated with Hb or HCT. The observed disparity in NAP1 and NAP2 levels by race/ethnicity is consistent with published literature. The origin of these differences in exposure is unclear but may reflect differences in environmental exposure as well as genetic susceptibility. The positive association between NAP1 with HCT and Hb is an unexpected finding. Further research is needed to understand the possible biological mechanisms or other explanations for this association.

Urinary 1-hydroxypyrene as a biomarker of exposure to polycyclic aromatic hydrocarbons: biological monitoring strategies and methodology for determining biological exposure indices for various work environments

This article reviews the published studies on urinary 1-hydroxypyrene (1-OHP) as a biomarker of exposure to polycyclic aromatic hydrocarbons (PAHs) in work environments. Sampling and analysis strategies as well as a methodology for determining biological exposure indices (BEIs) of 1-OHP in urine for different work environments are proposed for the biological monitoring of occupational exposure to PAHs. Owing to the kinetics of absorption of pyrene by different exposure routes and excretion of 1-OHP in urine, in general, 1-OHP urinary excretion levels increase during the course of a workday, reaching maximum values 3-9 h after the end of work. When the contribution of dermal exposure is important, post-shift 1-OHP excretion can however be lower than pre-shift levels in the case where a worker has been exposed occupationally to PAHs on the day prior to sampling. In addition, 1-OHP excretion levels in either pre-shift, post-shift or evening samples increase during the course of a work-week, levelling off after three consecutive days of work. Consequently, ideally, for a first characterization of a work environment and for an indication of the major exposure route, considering a 5-day work-week (Monday to Friday), the best sampling strategy would be to collect all micturitions over 24 h starting on Monday morning. Alternatively, collection of pre-shift, post-shift and evening urine samples on the first day of the work-week and at the end of the work-week is recommended. For routine monitoring, pre-shift samples on Monday and post-shift samples on Friday should be collected when pulmonary exposure is the main route of exposure. On the other hand, pre-shift samples on Monday and Friday should be collected when the contribution of skin uptake is important. The difference between beginning and end of work-week excretion will give an indication of the average exposure over the workweek. Pre-shift samples on the first day of the work-week will indicate background values, and, hence, reflect general environment exposure and body burden of pyrene and/or its metabolites. On the other hand, since PAH profile can vary substantially in different work sites, a single BEI cannot apply to all workplaces. A simple equation was therefore developed to establish BEIs for workers exposed to PAHs in different work environments by using a BEI already established for a given work environment and by introducing a correction factor corresponding to the ratio of the airborne concentration of the sum of benzo(a)pyrene (BaP) equivalent to that of pyrene. The sum of BaP equivalent concentrations represents the sum of carcinogenic PAH concentrations expressed as BaP using toxic equivalent factors. Based on a previously estimated BEI of 2.3 μmol 1-OHP mol(-1) creatinine for coke-oven workers, BEIs of 4.4, 8.0 and 9.8 μmol 1-OHP mol(-1) creatinine were respectively calculated for vertical pin Söderberg workers, anode workers and pre-bake workers of aluminium plants and a BEI of 1.2 μmol 1-OHP mol(-1) creatinine was estimated for iron foundry workers. This approach will allow the potential risk of cancer in individuals occupationally exposed to PAHs to be assessed better.

Spectrofluorimetric determination of zinc using 8-hydroxy-7-(4-sulfo-1-naphthylazo)-5-quinoline sulfonic acid

A sensitive and a selective spectrofluorimetric method have been developed for the rapid determination of zinc. The method is based on the complex formation between zinc and 8-hydroxy-7-(4-sulfo-1-naphthylazo)-5-quinoline sulfonic acid (HSNQ). The optimum conditions for the complex formation were metal to ligand stoichiometric ratio of 1:1 at pH 8.0 with 0.2M acetate buffer. The fluorescence of the complex is monitored at an emission wavelength of 545 nm with excitation at 360 nm. Under these conditions linear calibration curves were obtained from 50 ppb to 400 ppb. The detection limit was 7 ppb. The maximum relative standard deviation of the method was 2% for water samples, 4% for milk samples and 7% for hair samples (n = 5). The method was successfully applied for the determination of zinc in drinking water, hair and milk samples. The results were found to be in good agreement with those obtained by flame atomic absorption spectrophotometric methods. The t-test and F-test indicated no significant difference at 95% confidence level.

Comparison of the urinary excretion time courses of pyrene-1,6-dione, pyrene-1,8-dione and 1-hydroxypyrene in rats intravenously exposed to pyrene

The urinary excretion time courses of pyrene-1,6-dione (P16D), pyrene-1,8-dione (P18D) and 1-hydroxypyrene (1-OHP) were compared in Sprague-Dawley and Wistar rats. Groups of five male rats, of about 200 g of body weight, were injected intravenously with 0.05, 0.5, 5 and 50 micromol pyrene kg-1 of body weight. Urine was collected at 2, 4, 6, 8, 10, 12, 18, 24, 30, 42 and 48 h post-dosing. Pyrene metabolites were measured by high-performance liquid chromatography (HPLC)/fluorescence after enzymatic hydrolysis of the glucurono- and sulfo-conjugates, extraction on Sep-Pak C18 cartridges and, for the analysis of dione metabolites, derivatization to stable diacetoxypyrene molecules. Over the 48-h sampling period, on average 17.4-25.6% of the injected pyrene was excreted overall as P16D, 6.4-8.8% as P18D and 0.6-0.8% as 1-OHP in the urine of Sprague-Dawley rats. By comparison, on average 10.3-14.7% of the intravenous pyrene dose was recovered as P16D, 4.8-6.4% as P18D and 0.3-0.4% as 1-OHP in the urine of Wistar rats. In both strains of rats there was no clear effect of the dose on the 0-48-h cumulative urinary excretion of P18D and 1-OHP over the entire dose range, while the percentage of dose recovered overall as P16D in urine at the highest dose (50 micromol kg-1) was statistically lower than at the other doses. The 0-48-h cumulative percentage of pyrene dose excreted as metabolites in the urine of Sprague-Dawley rats was also significantly higher than in Wistar rats (p<0.01) exposed under identical conditions. As for the urinary excretion-time courses of the different metabolites, for a given dose and strain of rats, excretion curves of P16D, P18D and 1-OHP generally evolved in parallel. There was also no clear effect of the dose on the excretion rate, thus half-life, of pyrene metabolites, except for P16D in Sprague-Dawley rats at the highest dose where elimination tended to be slower compared with the other doses (p<0.01). The average first-order elimination half-life of P16D, P18D and 1-OHP was 4.0, 5.7 and 4.1 h, respectively, in Sprague-Dawley rats, and 5.1, 6.1 and 5.1 h, respectively, in Wistar rats (all doses combined but excluding the highest dose for P16D). This study showed the relative importance of metabolic pathways leading to diones compared with 1-OHP. These dioxygenated metabolites appear to be interesting biomarkers of pyrene exposure at environmentally and occupationally relevant doses. Their adequacy as biomarkers of human exposure has yet to be confirmed.

A sequential injection method for the fluorimetric determination of aluminum in drinking water using 8-hydroxy-7-(4-sulfo-1-naphthylazo)-5-quinoline sulfonic acid

A robust and simple sequential injection (SI) method for the assay of aluminum ions in drinking water is described. The method is based on the complex formation between aluminum and 8-hydroxy-7-(4-sulfo-1-naphthylazo)-5-quinoline sulfonic acid (HSNQ). The fluorescence of the complex is monitored at an emission wavelength of 492 nm with excitation at 357 nm. The HSNQ concentration, aspirated reagent and sample volumes were optimized simultaneously using 3(3) full factorial design. The optimum operating conditions are aspirated sample and reagent volumes of 90 and 70 microL, respectively, and HSNQ concentration of 20 microM. With these conditions linear calibration curves were obtained from 100 to 800 ppb. The detection limit was 4 ppb. The maximum relative standard deviation of the method was 1.43% (n=5). The method was successfully applied for the determination of aluminum in drinking water samples.

Reference values for exposure to PAH contaminants: Comparison of fish from Ohio and Mid-Atlantic streams

Reference values for background exposures of benzo[a]pyrene (BAP)- and naphthalene (NAPH)-type metabolites were calculated for white sucker, northern hog sucker, and rock bass from the mid-Atlantic region based on the 90th percentile of a probability-based sample. Preliminary findings are presented for common carp. Bile was collected from fish and assayed for polycyclic aromatic hydrocarbon metabolites using the fluorescent method of Lin et al. Exposure reference values for white sucker were 0.3 microg/mg protein for BAP-type metabolites and 40 microg/mg protein for NAPH-type metabolites. Values from the Mid-Atlantic region were similar to those previously reported for the Eastern Corn Belt Plains (ECBP) ecoregion. Exposure reference values of BAP-type metabolites for rock bass were 0.3 microg/mg protein and 0.4 microg/mg protein for northern hog sucker. Exposure reference values of NAPH-type metabolites for rock bass were 30 microg/mg protein for rock bass and 50 microg/mg protein for northern hog sucker. Provisional values for common carp based on 39 observations are 0.4 microg/mg protein for BAP-type metabolites and 120 microg/mg protein for NAPH-type metabolites. Small streams exhibited the greatest range of exposures, 0.015-0.689 microg/mg protein for BAP-type metabolites and from 5.7 to 159 microg/mg protein for NAPH-type metabolites. Larger streams had 0.11-0.859 microg/mg protein for BAP-type metabolites and 10.2-286.5 microg/mg protein for NAPH-type metabolites. Exposure reference values for BAP and NAPH-type metabolites could be used as a basis of comparison of exposure to PAH contamination.

Assessment of soil remediation workers' exposure to polycyclic aromatic hydrocarbons (PAH): biomonitoring of naphthols, phenanthrols, and 1-hydroxypyrene in urine

Urinalysis of multiple polycyclic aromatic hydrocarbons (PAH) biomarkers has been applied to assess the exposure of soil remediation workers on a former creosote wood impregnation site polluted with creosote oil. The uptake of PAHs was measured in preshift, end-of-shift, evening, and next preshift specimens (n=33) of nine volunteers with diverse tasks, using sensitive HPLC-FD methods. The ranges of biomarker concentrations in urine (nmol/l) were: 1-naphthol (14-159), 2-naphthol (9-166), 1- plus 2-naphthol (35-269), 1-hydroxyphenanthrene (OHPhe) (6-56), 2- plus 3-OHPhe (6-70), 4-OHPhe (1-6), 9-OHPhe (1-7), the sum of phenanthrols (15-135), and 1-hydroxypyrene, OHP (2.2-67). Eight of nine workers had OHP levels higher than the Finnish biological limit value for non-occupationally exposed persons (3nmol/l). A linear correlation was observed between 1- and 2-naphthol (r=0.90). The biomarker OHP correlated well in urine both with the major (1-OHPhe, r=0.96; 2- plus 3-OHPhe, r=0.84) and the minor phenanthrene metabolites (4-OHPhe, r=0.77; 9-OHPhe, r=0.68), and with the sum of all phenanthrols (r=0.94), but not so well with the sum of naphthols (r=0.66, p<0.001). The smokers had 2.9-, 2.2-, and 4.8-fold higher average concentrations of naphthols, phenanthrols, and OHP, respectively, than the non-smokers. The PAH biomarker data (concentrations and diurnal excretion profiles) showed significant work-related exposure in both non-smoking and smoking subjects. The average exposure levels were clearly higher than those we have measured for instance in asphalt paving workers. The workers' exposure should be assessed by biological monitoring, because at this type of outdoor work the dermal and pulmonary uptake of PAHs are both likely. Adequate measures for preventing, particularly, dermal absorption are of crucial importance for reducing the workers' risk of exposure to carcinogens on soil remediation sites.

Improved Method for Determination of 1-Hydroxypyrene in Human Urine

We have developed an improved method for the analysis of human urine for 1-hydroxypyrene (1-HOP), an accepted biomarker of polycyclic aromatic hydrocarbon uptake. This method takes advantage of commercially available 96-well format devices, which expedite sample preparation before quantitation by HPLC with fluorescence detection. In addition to improved speed of analysis, which is critical for the application of this assay in molecular epidemiology studies, the method described here uses an internal standard, 1-hydroxybenz[a]anthracene, improved sample preparation methods, and optimized HPLC and fluorescence detection conditions. The resulting method for analysis of 1-HOP is sensitive (detection limit, 0.05 pmol/mL urine), accurate (as determined by known addition of 1-HOP to urine), and precise [relative SD (RSD), 4.13%]. A longitudinal study of 1-HOP levels in the urine of 10 nonsmokers showed considerable day-to-day (mean RSD, 55.1 %) and week-to-week (mean RSD, 38.2 %) intra-individual variation, indicating the necessity for multiple sampling in studies concerned with relatively small differences in polycyclic aromatic hydrocarbon exposure.

Selective detection of monohydroxy metabolites of polycyclic aromatic hydrocarbons in urine using liquid chromatography/triple quadrupole tandem mass spectrometry

Polycyclic aromatic hydrocarbons (PAHs) are ubiquitously present in the environment and associated with a variety of adverse health effects. Monohydroxylated PAHs (OH-PAHs), metabolites of PAHs, have been employed as biomarkers for human exposure assessment of PAHs. This manuscript describes new, selective detection methods for OH-PAHs using liquid chromatography and tandem mass spectrometry (LC/MS/MS). Electrospray ionization was operated in the negative ion mode to detect the deprotonated PAH metabolites ([M-H](-)). Hydroxylated metabolites of naphthalene, fluorene, phenanthrene, fluoranthene, pyrene, benzo[c]phenanthrene, chrysene, benzo[a]anthracene, and benzo[a]pyrene were selected for the method development. Based on the collision-induced dissociation MS/MS spectra of the selected OH-PAHs, a characteristic ion fragmentation, loss of 28 Da from the [M--H](-) ion, was identified for all of these OH-PAHs. This characteristic fragmentation was exploited for selective screening for OH-PAHs in human urine by incorporating a constant neutral loss (CNL) scan with data-dependent scanning, using a triple quadruple mass spectrometer. Selected reaction monitoring (SRM) was also used to tentatively identify isomers of the target OH-PAHs in human urine. The excellent linearity (3-4 orders of magnitude) and signal-to-noise performance provided by the SRM method allowed development of a sensitive LC/MS/MS method for measuring OH-PAHs in urine samples. The limits of detection of the SRM method ranged from approximately 0.1-5 pg on column for a suite of OH-PAHs tested in the study. The LC-SRM method was applied, following enzymatic deconjugation and solid-phase extraction of the urine, to preliminarily determine the OH-PAH concentrations in urine specimens from six Chinese non-occupationally exposed workers and seven Chinese coke oven workers.

Urinary 1-hydroxypyrene and mutagenicity in bus drivers and mail carriers exposed to urban air pollution in Denmark

BACKGROUND

Previous studies in Denmark have shown that bus drivers and tramway employees were at an increased risk for developing several types of cancer and that bus drives from central Copenhagen have high levels of biomarkers of DNA damage.

AIMS

The present study evaluates 1-hydroxypyrene concentrations and mutagenic activity in urine as biomarkers of exposure in non-smoking bus drivers in city and rural areas on a work day and a day off and in non-smoking mail carriers working outdoors (in the streets) and indoors (in the office).

METHODS

Twenty-four hour urine samples were collected on a working day and a day off from 60 non-smoking bus drivers in city and rural areas and from 88 non-smoking mail carriers working outdoors (in the streets) and indoors (in the office). The concentration of 1-hydroxypyrene was measured by means of HPLC and the mutagenic activity was assessed by the Ames assay with Salmonella tester strain YG1021 and S9 mix. The N-acetyltransferase (NAT2) phenotype was used as a biomarker for susceptibility to mutagenic/carcinogenic compounds.

RESULTS

Bus drivers excreted more 1-hydroxypyrene in urine than did mail carriers. The differences were slightly smaller when NAT2 phenotype, cooking at home, exposure to vehicle exhaust, and performing physical exercise after work were included. The NAT2 slow acetylators had 29% (1.29 [CI: 1.15-1.98]) higher 1-hydroxypyrene concentrations in urine than the fast acetylators. Male bus drivers had 0.92 revertants/mol creatinine [CI: 0.37-1.47] and female bus drivers 1.90 revertants/mol creatinine [CI: 1.01-2.79] higher mutagenic activity in urine than mail carriers.

CONCLUSION

The present study indicates that bus drivers are more exposed to polycyclic aromatic hydrocarbons (PAH) and mutagens than mail carriers. Mail carriers who worked outdoors had higher urinary concentration of 1-hydroxypyrene, a marker of exposure to PAH, than those working indoors. The individual levels of urinary mutagenic activity were not correlated to excretion of 1-hydroxypyrene. This might be due to the fact that the most potent mutagenic compounds in diesel exhaust are not PAH but dinitro-pyrenes. Among bus drivers, fast NAT2 acetylators had higher mutagenic activity in urine than slow NAT2 acetylators and female bus drivers had higher mutagenic activity than male bus drivers.

Urinary hydroxy-metabolites of naphthalene, phenanthrene and pyrene as markers of exposure to diesel exhaust

OBJECTIVE

The objective of this study was to assess the exposure of bus-garage and waste-collection workers to polycyclic aromatic hydrocarbons (PAHs) derived from diesel exhaust by the measurement of levels of seven urinary PAH metabolites: 2-naphthol, 1-hydroxyphenanthrene, 2-hydroxyphenanthrene, 3-hydroxyphenanthrene, 1+9-hydroxyphenanthrene, 4-hydroxyphenanthrene and 1-hydroxypyrene.

SUBJECTS AND METHODS

One urine sample from each of 46 control persons, and one pre-shift and two post-shift spot urine samples from 32 exposed workers were obtained in winter and in summer. The metabolites were analysed after enzymatic hydrolysis by high performance liquid chromatography (HPLC) with fluorescence detection.

RESULTS

The sum of seven PAH metabolites (mean 3.94 +/- 3.40 and 5.60 +/- 6.37 micromol/mol creatinine in winter and summer, respectively) was higher [P=0.01, degrees of freedom (df) =61.2 and P=0.01, df=67.6 in winter and summer, respectively] in the exposed group than in the control group (mean 3.18 +/- 3.99 and 3.03 +/- 2.01 micromol/mol creatinine in winter and summer, respectively). The mean concentrations of 2-naphthol among exposed and controls ranged between 3.34 and 4.85 micromol/mol creatinine and 2.51 and 2.58 micromol/mol creatinine, respectively (P<0.01 in winter, P<0.03 in summer). The mean level of the hydroxyphenanthrenes in the samples of exposed workers was between 0.40 and 0.70 micromol/mol creatinine and in the control samples 0.40-0.60 micromol/mol creatinine. The concentration of 1-hydroxypyrene was higher among exposed workers in both pre-shift and post-shift samples (mean 0.10-0.15 micromol/mol creatinine) than in control group (mean 0.05-0.06 micromol/mol creatinine) in winter (P=0.002, df=78) and in summer (P<0.001, df=68).

CONCLUSIONS

The urinary hydroxy-metabolites of naphthalene, phenanthrene and pyrene showed low exposure to diesel-derived PAHs; however, it was higher in exposed workers than in control group. Urinary PAH monohydroxy-metabolites measured in this study did not correlate with the PAHs in the air samples, reported earlier, in 2002 and 2003.

Simultaneous determination of urinary 1- and 2-naphthols, 3- and 9-phenanthrols, and 1-pyrenol in coke oven workers

A method was developed for simultaneous quantification of urinary 1- and 2-naphthols, 3- and 9-phenanthrols and 1-pyrenol using gas chromatography with mass spectrometry (GC-MS). This method was applied to urine samples from coke oven workers (n=28) and controls (n=22) from Northern China. Geometric mean levels of urinary 1-naphthol (58.8 microg l(-1)), 2-naphthol (34.1 microg l(-1)), 3-phenanthrol (7.35 microg l(-1)), 9-phenanthrol (1.28 microg l(-1)) and 1-pyrenol (25.4 microg l(-1)) were significantly higher among coke oven workers than controls. All the substances tested were highest among top-of-oven workers, who had 15-fold higher 1-naphthol, eight-fold higher 2-naphthol and 20-fold higher 1-pyrenol levels compared with controls. Using multiple linear regression models, 72.5% of the variation in 1- and 2-naphthol and 82.8% of the variation in 1-pyrenol were explained by the concentration of naphthalene or pyrene in the urine, the work category and the smoking intensity. Cigarette consumption significantly contributed to levels of urinary 1-pyrenol and naphthols, particularly 2-naphthol. A negative relationship between work category and the ratio of naphthols/1-pyrenol was observed among smokers. Our results suggest that urinary naphthols and phenanthrols reflect polycyclic aromatic hydrocarbon (PAH) exposure as well as the widely used 1-pyrenol, and that interactions between cigarette smoking and PAH exposure result in different patterns of metabolism for individual PAHs.

Biomonitoring of environmental polycyclic aromatic hydrocarbon exposure by simultaneous measurement of urinary phenanthrene, pyrene and benzo[a]pyrene hydroxides

A high-performance liquid chromatographic method with fluorescence detection was developed which enables the simultaneous determination of the urinary polycyclic aromatic hydrocarbon metabolites 3-hydroxyphenanthrene, 1-hydroxypyrene and 3-hydroxybenzo[a]pyrene. The method has small solvent consumption because of the use of a microbore RP C18 column and a relatively short run time. Low detection limits of 0.02 nmol/l for 3-hydroxypyrene to 0.19 nmol/l for 3-hydroxybenzo[a]pyrene were attained. In contrast, the detection limits of alpha-naphthol and 9,10-dihydroxy-9,10-dihydrophenanthrene were not adequate for the determination of environmental exposure. The developed method was successfully used for the analysis of urine samples from children.

Assay of 2-naphthol in human urine by high-performance liquid chromatography

This paper describes a novel liquid chromatographic method for the quantitation of 2-naphthol in human urine. Urine samples were extracted after enzymatic hydrolysis of glucuronides and sulfates; 2-naphthol was then separated using reversed-phase high-performance liquid chromatography. The corresponding detection limits were 0.04 ng/ml for the standard sample in acetonitrile and 0.13 ng/ml for urine samples. The level of urinary 2-naphthol in 100 Korean shipyard workers was analyzed using this new method. The level ranged from 0.21 ng/ml (0.26 micromol/mol creatinine) to 34.19 ng/ml (59.11 micromol/mol creatinine), and the mean+/-standard deviation was 5.08 ng/ml (6.60 micromol/mol creatinine)+/-5.75 ng/ml (9.22 micromol/mol creatinine). The mean+/-standard deviation of urinary 2-naphthol level of smokers, 7.03 ng/ml (8.49 micromol/mol creatinine)+/-6.16 ng/ml (10.23 micromol/mol creatinine), was significantly higher than that of non-smokers, 2.49 ng/ml (4.10 micromol/mol creatinine)+/-3.92 ng/ml (7.03 micromol/mol creatinine).

Fast screening method for the profile analysis of polycyclic aromatic hydrocarbon metabolites in urine using derivatisation--solid-phase microextraction

A method for the qualitative analysis of various metabolites of naphthalene, phenanthrene and pyrene is presented. The method uses SPME with a 85-microm polyacrylate fibre for extraction, headspace silylation with BSTFA without any catalyst for on-fibre derivatisation and GC-MS in the SIR mode for separation and detection. The suitability of the method for profile analysis of PAH metabolites is shown by analysing a smokers urine after enzymatic cleavage (and additionally after spiking with the target analytes) and spiked water. The method exhibits satisfactory separation of all investigated metabolites and no interferences due to matrix peaks.

Assessment of exposure to polycyclic aromatic hydrocarbons in engine rooms by measurement of urinary 1-hydroxypyrene

OBJECTIVE

Machinists have an increased risk of lung cancer and bladder cancer, and this may be caused by exposure to carcinogenic compounds such as asbestos and polycyclic aromatic hydrocarbons (PAHs) in the engine room. The aim of this study was to investigate the exposure of engine room personnel to PAHs, with 1-hydroxypyrene in urine as a biomarker.

METHODS

Urine samples from engine room personnel (n = 51) on 10 ships arriving in different harbours were collected, as well as urine samples from a similar number of unexposed controls (n = 47) on the same ships. Urinary 1-hydroxypyrene was quantitatively measured by high performance liquid chromatography. The exposure to PAHs was estimated by a questionnaire answered by the engine room personnel. On two ships, air monitoring of PAHs in the engine room was performed at sea. Both personal monitoring and area monitoring were performed. The compounds were analysed by gas chromatography of two types (with a flame ionisation detector and with a mass spectrometer).

RESULTS

Significantly more 1-hydroxypyrene was found in urine of personnel who had been working in the engine room for the past 24 hours, than in that of the unexposed seamen. The highest concentrations of 1-hydroxypyrene were found among engine room personnel who had experienced oil contamination of the skin during their work in the engine room. Stepwise logistic regression analysis showed a significant relation between the concentrations of 1-hydroxypyrene, smoking, and estimated exposure to PAHs. No PAHs were detected in the air samples.

CONCLUSION

Engine room personnel who experience skin exposure to oil and oil products are exposed to PAHs during their work. This indicates that dermal uptake of PAHs is the major route of exposure.