Occupational Polycyclic Aromatic Hydrocarbons Research Articles

Environmental exposure to polycyclic aromatic hydrocarbons: An underestimated risk factor for systemic lupus erythematosus onset and progression

ObjectiveTo investigate the link between systemic lupus erythematosus (SLE) incidence and exposure to environmental polycyclic aromatic hydrocarbons (PAH). MethodsA case-control study (ChiCTR2000038187) involving 316 SLE patients and 851 healthy controls (HCs) was executed. Environmental exposure was assessed via a questionnaire, stratified by gender and age (females <35 and ≥35 years, males). Blood samples collected from 89 HCs, 85 inactive, and 95 active SLE patients were used to measure serum benzo[a]pyrene diol epoxide -albumin (BPDE-Alb) adducts and PAH concentrations, indicating long-term and short-term exposure respectively. Intergroup comparisons and statistical analyses were conducted using R version 4.3.1. ResultsDiverse patterns were found in how environmental factors affect SLE onset across different demographics. Lifestyle exposure factors were found to be a stronger determinant of SLE onset than occupational exposure factors in women under 35. Indoor air pollution had a significant impact on SLE incidence, potentially comparable to outdoor air pollution. Lifestyle-related PAH exposure had a greater impact on SLE than occupational PAH exposure. PAH exposure levels progressively increase from HCs to inactive and active SLE patients. Active SLE patients show markedly higher BPDE-Alb levels than HCs. ConclusionsEnvironmental PAH, particularly lifestyle-related, are significant, yet under-recognized, risk factors for SLE. Statement of environmental implicationWe examined the relationship between exposure to environmental polycyclic aromatic hydrocarbons (PAH) and the incidence of systemic lupus erythematosus (SLE). PAH, prevalent in sources such as cigarette smoke, air pollution, and charred food, pose significant health hazards. This study is the first to investigate specific PAH exposure levels in SLE patients. We determined actual PAH exposure levels in both SLE patients and healthy individuals and indicated that long-term PAH exposure biomarker is more reliable for evaluating exposure in non-occupationally exposed groups like SLE, compared to short-term markers. These findings provide valuable insights for future research on similar non-occupationally exposed populations.

The effect of high polycyclic aromatic hydrocarbon exposure on biological aging indicators

BackgroundAging represents a serious health and socioeconomic concern for our society. However, not all people age in the same way and air pollution has been shown to largely impact this process. We explored whether polycyclic aromatic hydrocarbons (PAHs), excellent fossil and wood burning tracers, accelerate biological aging detected by lymphocytes DNA methylation age (DNAmAge) and telomere length (TL), early nuclear DNA (nDNA) hallmarks of non-mitotic and mitotic cellular aging, and mitochondrial DNA copy number (mtDNAcn).MethodsThe study population consisted of 49 male noncurrent-smoking coke-oven workers and 44 matched controls. Occupational and environmental sources of PAH exposures were evaluated by structured questionnaire and internal dose (urinary 1-pyrenol). We estimated Occup_PAHs, the product of 1-pyrenol and years of employment as coke-oven workers, and Environ_PAHs, from multiple items (diet, indoor and outdoor). Biological aging was determined by DNAmAge, via pyrosequencing, and by TL and mtDNAcn, via quantitative polymerase chain reaction. Genomic instability markers in lymphocytes as target dose [anti-benzo[a]pyrene diolepoxide (anti-BPDE)–DNA adduct], genetic instability (micronuclei), gene-specific (p53, IL6 and HIC1) and global (Alu and LINE-1 repeats) DNA methylation, and genetic polymorphisms (GSTM1) were also evaluated in the latent variable nDNA_changes. Structural equation modelling (SEM) analysis evaluated these multifaceted relationships.ResultsIn univariate analysis, biological aging was higher in coke-oven workers than controls as detected by higher percentage of subjects with biological age older than chronological age (AgeAcc ≥ 0, p = 0.007) and TL (p = 0.038), mtDNAcn was instead similar. Genomic instability, i.e., genotoxic and epigenetic alterations (LINE-1, p53 and Alu) and latent variable nDNA_changes were higher in workers (p < 0.001). In SEM analysis, DNAmAge and TL were positively correlated with Occup_PAHs (p < 0.0001). Instead, mtDNAcn is positively correlated with the latent variable nDNA_changes (p < 0.0001) which is in turn triggered by Occup_PAHs and Environ_PAHs.ConclusionsOccupational PAHs exposure influences DNAmAge and TL, suggesting that PAHs target both non-mitotic and mitotic mechanisms and made coke-oven workers biologically older. Also, differences in mtDNAcn, which is modified through nDNA alterations, triggered by environmental and occupational PAH exposure, suggested a nuclear-mitochondrial core-axis of aging. By decreasing this risky gerontogenic exposure, biological aging and the consequent age-related diseases could be prevented.

Exposure to polycyclic aromatic hydrocarbons and the associations with oxidative stress in waste incineration plant workers from South China.

Waste incineration is one of the most common emission sources of polycyclic aromatic hydrocarbons (PAHs), causing potential occupational exposure in waste incineration workers. However, relative investigations among waste incineration plant workers are still very limited, particularly in China. Therefore, we collected urine specimens from 77 workers in a waste incineration plant as the exposed group, and 101 residents as the control group in Shenzhen, China. Nine mono-hydroxylated PAH metabolites (OH-PAHs) and 8-hydroxy-2'-deoxyguanosine (8-OHdG) were measured, and their internal relationships were explored. The urinary levels of most OH-PAHs and 8-OHdG in the exposed group exhibited high levels versus another group (p<0.05). We found negative associations between OH-PAHs and 8-OHdG in the control group (p<0.05), while most of OH-PAHs were not associated with 8-OHdG in the exposed group, which indicated that the exposure to waste incineration could enlarge the level of individual oxidative stress damage. Nevertheless, PAHs were less likely to trigger obvious health risks in exposed workers through estimation of human intake and exposure risks. This study provides a reference for occupational PAH exposure and strengthen the need of health monitoring among incineration workers.

Interactions between exposure to polycyclic aromatic hydrocarbons and xenobiotic metabolism genes, and risk of breast cancer.

Polycyclic aromatic hydrocarbons (PAHs) are a group of environmental pollutants associated with multiple cancers, including female breast cancer. Several xenobiotic metabolism genes (XMGs), including the CYP450 family, play an important role in activating and detoxifying PAHs, and variations in the activity of the enzymes they encode can impact this process. This study aims to examine the association between XMGs and breast cancer, and to assess whether these variants modify the effects of PAH exposure on breast cancer risk. In a case-control study in Vancouver, British Columbia, and Kingston, Ontario, 1037 breast cancer cases and 1046 controls had DNA extracted from blood or saliva and genotyped for 138 single nucleotide polymorphisms (SNPs) and tagSNPs in 27 candidate XMGs. Occupational PAH exposure was assessed using a measurement-based job-exposure matrix. An association between genetic variants and breast cancer was observed among six XMGs, including increased risk among the minor allele carriers of AKR1C3 variant rs12387 (OR 2.71, 95% CI 1.42-5.19) and AKR1C4 variant rs381267 (OR 2.50, 95% CI 1.23-5.07). Heterogeneous effects of occupational PAH exposure were observed among carriers of AKR1C3/4 variants, as well as the PTGS2 variant rs5275. Our findings support an association between SNPs of XMGs and female breast cancer, including novel genetic variants that modify the toxicity of PAH exposure. These results highlight the interplay between genetic and environmental factors, which can be helpful in understanding the modifiable risks of breast cancer and its complex etiology.

Benchmark dose analysis for PAHs hydroxyl metabolites in urine based on mitochondrial damage of peripheral blood leucocytes in coke oven workers in China

ObjectivesThe aim was to explore the dose-response relationship between occupational polycyclic aromatic hydrocarbons (PAHs) exposure and mitochondrial damage in coke oven plants workers. Methods544 workers and 238 healthy people were recruited. The ultra-high performance liquid chromatography was used to determine the level of 1-hydroxypyrene, 1-hydroxynaphthalene, 2-hydroxynaphthalene and 3-hydroxyphenanthrene. The real-time fluorescence quantitative polymerase chain reaction was used to determine the mitochondrial DNA copy number (mtDNAcn). The benchmark dose software was used to analyze the benchmark dose. ResultsThe mtDNAcn in the exposure group was lower than that in the control group. The concentrations of 1-hydroxypyrene, 1-hydroxynaphthalene, 2-hydroxynaphthalene and 3-hydroxyphenanthrene in the exposure group were higher than those in the control group. There is a dose-response relationship between 1-hydroxypyrene, 3-hydroxyphenanthrene and mitochondrial DNA damage. The benchmark dose lower confidence limit (BMDL) of 1-hydroxypyrene were 0.045, 0.004, and 0.058 pg/μg creatinine in the total, male, and female population, respectively. The BMDL of 3-hydroxyphenanthrene were 5.142, 6.099, and 2.807 pg/μg creatinine in the total, male, and female population, respectively. ConclusionsThe BMDL of 1-hydroxypyrene and 3-hydroxyphenanthrene initially explored can provide a reference to establish occupational exposure biological limits.

Polycyclic aromatic hydrocarbon metabolites and mortality risk in an adult population

Occupational polycyclic aromatic hydrocarbons (PAHs) exposure has been shown to increase the risk of various cancers and may be associated with carcinogenic mortality. However, no study has explored the relationship between environmental PAH exposure and mortality in general population. The aim of our study was to explore the association between PAH exposure and all-cause, cardiovascular, and cancer mortality in a general US adult population. We analyzed data from the National Health and Nutrition Examination Survey (NHANES 2001-2006) based on the information in this dataset on 692 males and 717 females. PAH exposure was detected using biomarkers from urine samples. Follow-up data on mortality were derived from initial examination of the subjects until death or 31 December 2006 in the NHANES database. We calculated hazard ratios (HRs) of PAH metabolites among all-cause, cardiovascular, and cancer mortality using the multivariate Cox proportional hazards regression model after adjusting for covariates. Among males, 3-phenanthrene was positively associated with increased risk of all-cause mortality (HR 1.043, 95%CI 1.019-1.066). Female participants with higher 2-napthol (HR 1.043, 95%CI 1.014-1.072), 3-fluorene (HR 2.159, 95%CI 1.233-3.779), and 1-phenanthrene (HR = 1.259, 95%CI 1.070-1.481) levels had increased all-cause mortality. In addition, high 3-phenanthrene (HR 1.333, 95%CI 1.008-1.763) and 1-phenanthrene (HR 1.463, 95%CI 1.126-1.900) levels increased the risk of cardiovascular mortality. However, there were no significant findings for cancer mortality in both genders. Environmental PAH exposure among the adult population is associated with non-carcinogenic but not cancer mortality. Future studies are warranted to determine the underlying mechanisms related to these findings.

Maternal occupational exposure to polycyclic aromatic hydrocarbons and the risk of isolated congenital heart defects among offspring

BackgroundAlthough there is evidence in experimental model systems that exposure to polycyclic aromatic hydrocarbons (PAHs) is linked with congenital heart defects (CHDs), few studies have examined the association in humans. We conducted a case-control study to examine the association between maternal exposure to PAHs and CHDs in offspring using data from the National Birth Defects Prevention Study (NBDPS) (1997–2011). MethodsWe obtained detailed information on maternal occupation during the month before to three months after conception. Expert raters, masked to case-control status, assessed job descriptions to assign categorical levels of exposure. Categories were quantitatively mapped to estimate cumulative exposure to PAHs, incorporating exposure intensity, frequency, work duration, and work hours. Quartiles were generated for cumulative maternal exposure to PAHs. Crude and adjusted odds ratios (ORs) with 95% confidence intervals (CIs) were estimated using unconditional logistic regression for quartiles of PAH exposure and six CHD groupings (e.g. conotruncal) and specific subtypes (e.g. tetralogy of Fallot [ToF]). Final models were adjusted for maternal age, race/ethnicity, education, smoking, anticonvulsant use, folic acid supplementation, and study center. ResultsThere were 4,775 case and 7,734 control infants eligible for the study. The prevalence of occupational exposure to PAHs was 10.2% among both case and control mothers. In adjusted analysis, compared to mothers with no occupational PAH exposure, those in the highest quartile of exposure were more likely to have offspring in the conotruncal heart defects group (OR 1.41; 95% CI 1.00–2.00), and with ToF (OR 1.83; 95% CI 1.21–2.78). ConclusionsWomen in the highest quartile of estimated cumulative occupational PAH exposure during early pregnancy were more likely to have offspring with conotruncal heart defects, specifically ToF, compared to women with no occupational PAH exposure. Other comparisons between PAHs and other CHDs subgroups did not show any statistically precise associations.

Association between maternal occupational exposure to polycyclic aromatic hydrocarbons and rare birth defects of the face and central nervous system.

Previous studies suggested associations between maternal smoking, a source of exposure to polycyclic aromatic hydrocarbons (PAHs) and other chemicals, and central nervous system and face birth defects; however, no previous studies have evaluated maternal occupational PAH exposure itself. Jobs held in the periconceptional period were retrospectively assigned for occupational PAH exposures. Associations between maternal occupational PAH exposure and selected rare defects of the face (cataracts, microphthalmia, glaucoma, microtia, and choanal atresia) and central nervous system (holoprosencephaly, hydrocephaly, cerebellar hypoplasia, and Dandy-Walker malformation) were evaluated using data from the National Birth Defects Prevention Study, a population-based case-control study in the United States. Crude and adjusted odds ratios (ORs) with 95% confidence intervals were calculated to estimate associations between each evaluated defect and PAH exposure using multivariable logistic regression. Food and beverage serving, as well as cooks and food preparation occupations, were among the most frequent jobs held by exposed mothers. Cataracts, microtia, microphthalmia, and holoprosencephaly were significantly associated with PAH exposure with evidence of dose-response (P-values for trend ≤.05). Hydrocephaly was associated with any PAH exposure, but not significant for trend. Sensitivity analyses that reduced possible sources of exposure misclassification tended to strengthen associations. This is the first population-based case-control study to evaluate associations between maternal occupational PAH exposures and these rare birth defects of the central nervous system and face.

CYP1A1 methylation mediates the effect of smoking and occupational polycyclic aromatic hydrocarbons co-exposure on oxidative DNA damage among Chinese coke-oven workers

BackgroundMultiple factors, including co-exposure between lifestyle and environmental risks, are important in susceptibility to oxidative DNA damage. However, the underlying mechanism is not fully understood. This study was undertaken to evaluate whether Cytochrome P4501A1 (CYP1A1) methylation can mediate the co-exposure effect between smoking and occupational polycyclic aromatic hydrocarbons (PAH) in development of oxidative DNA damage.MethodsWe explored the associations between smoking and occupational PAH co-exposure effect, CYP1A1 methylation and oxidative DNA damage among 500 workers from a coke-oven plant in China. Urine biomarkers of PAH exposure (1-hydroxypyrene, 1-OHP; 2-hydroxynaphthalene, 2-NAP; 2-hydroxyfluorene, 2-FLU; and 9-hydroxyphenanthren, 9-PHE) and a marker of oxidative DNA damage (8-hydroxy- 2′- deoxyguanosine, 8-OHdG) were measured by high performance liquid chromatography. CYP1A1 methylation was measured by pyrosequencing. Finally, mediation analysis was performed to investigate whether CYP1A1 methylation mediated smoking and occupational PAH co-exposure effect on oxidative DNA damage.ResultsWe observed significant associations of smoking and 1-OHP co-exposure with CYP1A1 hypomethylation (OR: 1.87, 95% CI: 1.01–3.47) and high 8-OHdG (OR: 2.13, 95% CI: 1.14–3.97). There was a significant relationship between CYP1A1 hypomethylation and high 8-OHdG (1st vs. 3rd tertile = 1.58, 95% CI: 1.01–2.47, P for trend = 0.046). In addition, mediation analysis suggested CYP1A1 hypomethylation could explain 13.6% of effect of high 8-OHdG related to smoking and 1-OHP co-exposure.ConclusionsOur findings suggested that the co-exposure effect of smoking and occupational PAH could increase the risk of oxidative DNA damage by a mechanism partly involving CYP1A1 hypomethylation.

Association of polycyclic aromatic hydrocarbon exposure and CYP1A1 gene and enzyme activity of peripheral blood monocyte cells in coke oven workers

Objective: To explore the association between polycyclic aromatic hydrocarbons (PAHs) exposure and cytochrome P450 CYP1A1 expression at gene and enzyme activity levels in the peripheral blood monocyte cells in coke oven workers, and to provide a certain basis for the biological monitoring of health damage in coke oven workers. Methods: We surveyed 118 coke oven workers and 63 controls (energy power workers in the same company) using self-designed questionnaire, determined their post-shift urinary 1-hydroxypyrene (1-OH-Py) concentration using high performance liquid chromatography (HPLC)-fluorescence detector method. We also isolated the peripheral blood mononuclear cell (PBMC) from fasting venous blood, and detected DNA damage using comet assay, CYP1A1 mRNA level using the real-time fluorescent quantitative PCR (FQ-PCR), and EROD activity using spectrophotometry. Statistical analyses including one-way analysis of variance and multiple linear regressions were used to analyze the association of urinary 1-OH-Py and CYP1A1 mRNA level and EROD activity. Results: Compared to the control group, the urinary 1-OH-Py concentration and PBMC DNA tail moment were significantly increased in coke oven workers (P<0.05), and CYP1A1 gene level and EROD activity in PBMC were significantly decreased (P<0.05). Multiple linear regression showed that a ten-fold increase of urinary 1-OH-Pycon centration was associated with a decrease of 0.77 (95%CI: -1.33--0.21) in CYP1A1 gene level, and a decline of 0.15 (95%CI: -0.76--0.16) in EROD activity of PBMC in coke oven workers (P<0.05). Conclusion: Occupational PAHs exposure induced DNA damage, which was associated with the decreased level in CYP1A1 gene cavel and EROD activity in PBMC of coke oven workers.

Women’s occupational exposure to polycyclic aromatic hydrocarbons and risk of breast cancer

ObjectiveTo estimate the association between occupational polycyclic aromatic hydrocarbon (PAH) exposure and female breast cancer.MethodsLifetime work histories for 1130 cases and 1169 controls from British Columbia and Ontario (Canada) were...

Current strategies in the safety assessment of monoclonal antibodies

Naphthalene occurs together with polycyclic aromatic hydrocarbons (PAHs) at industrial workplaces and is ubiquitous in the environment. For biological monitoring of naphthalene exposures, up to now mainly 1- and 2-naphthol in urine have been used. Recently, we proposed 1,2-dihydroxynaphthalene (1,2-DHN) and the 1- and 2-naphthylmercapturic acid (1- and 2-NMA) as new urinary biomarkers to characterise a naphthalene exposure.In this study, in a collective of nine occupationally exposed workers handling with creosote the naphthalene metabolites 1,2-DHN, 1- and 2-NMA as well as 1- and 2-naphthol were analysed in order to evaluate the suitability of the different parameters for their application in biomonitoring studies. Additionally, air sampling was conducted to characterise the exposure in task related exposure situations at different workplaces.In the analysed 51 urine samples, 1,2-DHN was the main metabolite with concentrations ranging from 2.3 to 886 μg/g creatinine (crea) (median 34 μg/g crea). For the sum of 1- and 2-naphthol, concentrations in the range of 2.6–174 μg/g crea (median 15 μg/g crea) were observed. 1-NMA concentrations were in the range of < LOD-2.4 μg/g crea (61% > LOD), while 2-NMA was not detected in the analysed urine samples. The biomarkers 1,2-DHN, 1- and 2-naphthol as well as 1-NMA showed significant correlations, which pointed out to naphthalene as the common exposure source. The poor correlations between naphthalene in the air and the biomarkers in urine may be a result of the varying exposure situations and may indicate not solely inhalative, but additional dermal uptake.1,2-DHN was the most sensitive and, together with 1-NMA, the most specific parameter of the biological monitoring of naphthalene exposure at workplaces. Further studies with this parameter are needed for individuals at different workplaces as well as for persons of the general population without occupational PAH exposure to characterise 1,2-DHN levels as well as to establish their relationship with the naphthalene exposure.

Human skin-derived precursors and their applications in hepatic toxicology

Naphthalene occurs together with polycyclic aromatic hydrocarbons (PAHs) at industrial workplaces and is ubiquitous in the environment. For biological monitoring of naphthalene exposures, up to now mainly 1- and 2-naphthol in urine have been used. Recently, we proposed 1,2-dihydroxynaphthalene (1,2-DHN) and the 1- and 2-naphthylmercapturic acid (1- and 2-NMA) as new urinary biomarkers to characterise a naphthalene exposure.In this study, in a collective of nine occupationally exposed workers handling with creosote the naphthalene metabolites 1,2-DHN, 1- and 2-NMA as well as 1- and 2-naphthol were analysed in order to evaluate the suitability of the different parameters for their application in biomonitoring studies. Additionally, air sampling was conducted to characterise the exposure in task related exposure situations at different workplaces.In the analysed 51 urine samples, 1,2-DHN was the main metabolite with concentrations ranging from 2.3 to 886 μg/g creatinine (crea) (median 34 μg/g crea). For the sum of 1- and 2-naphthol, concentrations in the range of 2.6–174 μg/g crea (median 15 μg/g crea) were observed. 1-NMA concentrations were in the range of < LOD-2.4 μg/g crea (61% > LOD), while 2-NMA was not detected in the analysed urine samples. The biomarkers 1,2-DHN, 1- and 2-naphthol as well as 1-NMA showed significant correlations, which pointed out to naphthalene as the common exposure source. The poor correlations between naphthalene in the air and the biomarkers in urine may be a result of the varying exposure situations and may indicate not solely inhalative, but additional dermal uptake.1,2-DHN was the most sensitive and, together with 1-NMA, the most specific parameter of the biological monitoring of naphthalene exposure at workplaces. Further studies with this parameter are needed for individuals at different workplaces as well as for persons of the general population without occupational PAH exposure to characterise 1,2-DHN levels as well as to establish their relationship with the naphthalene exposure.

Application of systems biology to guide quantitative translation risk assessments

Naphthalene occurs together with polycyclic aromatic hydrocarbons (PAHs) at industrial workplaces and is ubiquitous in the environment. For biological monitoring of naphthalene exposures, up to now mainly 1- and 2-naphthol in urine have been used. Recently, we proposed 1,2-dihydroxynaphthalene (1,2-DHN) and the 1- and 2-naphthylmercapturic acid (1- and 2-NMA) as new urinary biomarkers to characterise a naphthalene exposure.In this study, in a collective of nine occupationally exposed workers handling with creosote the naphthalene metabolites 1,2-DHN, 1- and 2-NMA as well as 1- and 2-naphthol were analysed in order to evaluate the suitability of the different parameters for their application in biomonitoring studies. Additionally, air sampling was conducted to characterise the exposure in task related exposure situations at different workplaces.In the analysed 51 urine samples, 1,2-DHN was the main metabolite with concentrations ranging from 2.3 to 886 μg/g creatinine (crea) (median 34 μg/g crea). For the sum of 1- and 2-naphthol, concentrations in the range of 2.6–174 μg/g crea (median 15 μg/g crea) were observed. 1-NMA concentrations were in the range of < LOD-2.4 μg/g crea (61% > LOD), while 2-NMA was not detected in the analysed urine samples. The biomarkers 1,2-DHN, 1- and 2-naphthol as well as 1-NMA showed significant correlations, which pointed out to naphthalene as the common exposure source. The poor correlations between naphthalene in the air and the biomarkers in urine may be a result of the varying exposure situations and may indicate not solely inhalative, but additional dermal uptake.1,2-DHN was the most sensitive and, together with 1-NMA, the most specific parameter of the biological monitoring of naphthalene exposure at workplaces. Further studies with this parameter are needed for individuals at different workplaces as well as for persons of the general population without occupational PAH exposure to characterise 1,2-DHN levels as well as to establish their relationship with the naphthalene exposure.

Suitability of several naphthalene metabolites for their application in biomonitoring studies

Naphthalene occurs together with polycyclic aromatic hydrocarbons (PAHs) at industrial workplaces and is ubiquitous in the environment. For biological monitoring of naphthalene exposures, up to now mainly 1- and 2-naphthol in urine have been used. Recently, we proposed 1,2-dihydroxynaphthalene (1,2-DHN) and the 1- and 2-naphthylmercapturic acid (1- and 2-NMA) as new urinary biomarkers to characterise a naphthalene exposure.In this study, in a collective of nine occupationally exposed workers handling with creosote the naphthalene metabolites 1,2-DHN, 1- and 2-NMA as well as 1- and 2-naphthol were analysed in order to evaluate the suitability of the different parameters for their application in biomonitoring studies. Additionally, air sampling was conducted to characterise the exposure in task related exposure situations at different workplaces.In the analysed 51 urine samples, 1,2-DHN was the main metabolite with concentrations ranging from 2.3 to 886 μg/g creatinine (crea) (median 34 μg/g crea). For the sum of 1- and 2-naphthol, concentrations in the range of 2.6–174 μg/g crea (median 15 μg/g crea) were observed. 1-NMA concentrations were in the range of < LOD-2.4 μg/g crea (61% > LOD), while 2-NMA was not detected in the analysed urine samples. The biomarkers 1,2-DHN, 1- and 2-naphthol as well as 1-NMA showed significant correlations, which pointed out to naphthalene as the common exposure source. The poor correlations between naphthalene in the air and the biomarkers in urine may be a result of the varying exposure situations and may indicate not solely inhalative, but additional dermal uptake.1,2-DHN was the most sensitive and, together with 1-NMA, the most specific parameter of the biological monitoring of naphthalene exposure at workplaces. Further studies with this parameter are needed for individuals at different workplaces as well as for persons of the general population without occupational PAH exposure to characterise 1,2-DHN levels as well as to establish their relationship with the naphthalene exposure.

Urinary trans-anti-7,8,9,10-tetrahydroxy-7,8,9,10-tetrahydrobenzo(a)pyrene as the most relevant biomarker for assessing carcinogenic polycyclic aromatic hydrocarbons exposure

Polycyclic aromatic hydrocarbons (PAH) are ubiquitous pollutants present as complex mixtures in the environment. Among them, benzo(a)pyrene (BaP) is classified as carcinogenic to humans by the International Agency of Research on Cancer. Taking into account all absorption ways, human biomonitoring allows PAH exposure assessment, but biomarkers both specific to carcinogenic effect and sufficiently sensitive are lacking. In this work, we proposed the urinary 7,8,9,10-tetrahydroxy-7,8,9,10-tetrahydrobenzo(a)pyrene (7,8,9,10-OHBaP) stemming from hydrolysis of BaP-7,8-diol-9,10-epoxide, the ultimate carcinogenic BaP metabolite, as biomarker of PAH exposure. A simple and highly sensitive analytical method, with a limit of quantification (LQ) reaching 0.06pmol/L (0.02ng/L), was described and validated. The relevance of urinary 7,8,9,10-OHBaP concentrations adjustment by creatinine was demonstrated. In a group of 24 non-occupationally PAH exposed subjects, only 15% of 7,8,9,10-OHBaP levels was below the LQ and the last daily void has been found as the best sampling time. Tobacco consumption had a significant positive effect on 7,8,9,10-OHBaP concentrations with a 90e percentile equal to 0.05nmole/mole creatinine (nmol/mol) and 0.03nmol/mol for smokers and non-smokers, respectively. In case of occupational PAH exposure, all the pre- and post-shift urinary 7,8,9,10-OHBaP levels of 7 non-smoking workers in a prebaked electrodes production plant were above the LQ. Concentrations ranged from 0.05 to 0.91nmol/mol and accumulation of 7,8,9,10-OHBaP into organism of workers during the working week was clearly observed. The best sampling time was the post-shift at the end of week but samples should also be collected at pre-shift the beginning of week to assess the background level. Finally, the urinary 7,8,9,10-OHBaP elimination kinetic through the weekend was studied using non-linear mixed effect modelling. Mean apparent urinary half-life was 31.5h with low inter-individual variability. Describing key characteristics of urinary 7,8,9,10-OHBaP as PAH exposure biomarker, this work should promote its use for future large-scale biomonitoring campaigns.

Evaluation of polyurethane foam passive air sampler (PUF) as a tool for occupational PAH measurements

Routine monitoring of workplace exposure to polycyclic aromatic hydrocarbons (PAHs) is performed mainly via active sampling. However, active samplers have several drawbacks and, in some cases, may even be unusable. Polyurethane foam (PUF) as personal passive air samplers constitute good alternatives for PAH monitoring in occupational air (8 h). However, PUFs must be further tested to reliably yield detectable levels of PAHs in short exposure times (1–3 h) and under extreme occupational conditions. Therefore, we compared the personal exposure monitoring performance of a passive PUF sampler with that of an active air sampler and determined the corresponding uptake rates (Rs). These rates were then used to estimate the occupational exposure of firefighters and police forensic specialists to 32 PAHs. The work environments studied were heavily contaminated by PAHs with (for example) benzo(a)pyrene ranging from 0.2 to 56 ng m−3, as measured via active sampling. We show that, even after short exposure times, PUF can reliably accumulate both gaseous and particle-bound PAHs. The Rs-values are almost independent of variables such as the concentration and the wind speed. Therefore, by using the Rs-values (2.0–20 m3 day−1), the air concentrations can be estimated within a factor of two for gaseous PAHs and a factor of 10 for particulate PAHs. With very short sampling times (1 h), our method can serve as a (i) simple and user-friendly semi-quantitative screening tool for estimating and tracking point sources of PAH in micro-environments and (ii) complement to the traditional active pumping methods.

Effects of smoking on concentration of urinary 8-hydroxydeoxyguanosine in coke oven workers

Objective: To explore the influence of smoking and polycyclic aromatic hydrocarbons (PAHs) on urinary 8-hydroxydeoxyguanosine (8-OHdG) in coke oven workers and investigate their dose-dependent relationships. Methods: A total of 436 workers exposed to coke oven emissions (COEs) and 132 controls were recruited in this study. Questionnaires were completed in a personal interview. Then their urine samples were also collected and the concentrations of urinary four OH-PAHs and 8-OHdG were determined by high performance liquid chromatography (HPLC) which was used to evaluate the levels of occupational PAHs internal exposure among workers and the DNA damage. Results: The differences of concentrations of urinary 2-NAP (2-hydroxynathalene) , 2-FLU (2-hydroxyfluorene) , 9-PHE (9-hydroxyphenanthrene) , 1-OHP (1-hydroxypyrene) between exposure group and control group were statistically significant (P<0.05) . In exposure group and control group, the level of 8-OHdG in heavy smoking workers were significantly higher than that in other groups (P<0.05) . Multivariate logistic regression analysis revealed high levels of urinary 8-OHdG were associated with a significantly increased risk of having higher urinary1-hydroxypyrene levels[OR=1.43 (95%CI: 1.06-1.94) , P<0.01] and heavy smoking [OR=1.44 (95%CI: 1.08-1.91) , P<0.01], respectively. Trend test showed that linear dose response relationship between smoking, 1-OHP in urine and higher concentrations of 8-OHdG (P<0.05) . Smoking could significant modify the effects of urinary 1-hydroxypyrene, while co-exposure to both heavy smoking and high urinary 1-hydroxypyrene levels[OR=5.64 (95%CI: 2.15-14.80) , P<0.05]. Conclusion: Urinary 1-hydroxypyrene is a useful biomarker for evaluating total PAHs exposure, coke oven workers with heavy smoking present more serious DNA oxditive damage.

Association of polycyclic aromatic hydrocarbons metabolites and risk of diabetes in coke oven workers

Elevated polycyclic aromatic hydrocarbons (PAHs) metabolites have recently been linked to increased risk of diabetes in the general population, but little is known about the risk of diabetes due to high pollution levels of PAHs exposure. We aimed to examine whether occupational exposure to PAHs would be one of the important risk factors for diabetes in the coke oven workers. A total of 1472 coke oven workers with complete data were qualified for the present study. We measured 12 urinary monohydroxy polycyclic aromatic hydrocarbons (OH-PAHs) by gas chromatography–mass spectrometry (GC-MS). Multiple logistic regression was used to evaluate the associations between urinary OH-PAHs and risk of diabetes, with adjustment for the potential confounders. We found that elevated urinary 4-hydroxyphenanthrene (4-OHPh) was significantly associated, in a dose-dependent manner, with increased risk of diabetes (Ptrend = 0.003). Compared with individuals with 4-OHPh in the lowest quartile, the adjusted odds ratio (OR) of diabetes among those in the highest quartile was 2.80 (95% CI = 1.37–5.71). In stratified analysis, the association was more prominent in those who were smokers, overweight (BMI ≥24 kg/m2), with longer working years (≥20 years) and worked at coke oven settings. In addition, high levels of 4-OHPh combined with longer working years or overweight had a joint effect on the risk of diabetes. Our data suggested that elevated 4-OHPh was dose-responsive associated with increased risk of diabetes in the coke oven workers. The risk assessment of diabetes related to occupational PAHs exposure should take working years and BMI into consideration.

Characterization of the particulate matter and relationship between buccal micronucleus and urinary 1-hydroxypyrene levels among cashew nut roasting workers

The present study is the first assessment of occupational risk associated with artisanal cashew nut roasting using exposure and effect biomarkers, as well as a characterization and dispersion analysis of the released particulate matter (PM). A real-time particle monitor was used to quantify PM1.0, PM2.5 and PM10. Furthermore, the PM was sampled using a Handi-vol sampler, and the physicochemical characteristics were determined by SEM-EDS analysis. Trajectories, dispersion and deposition of the emitted material were calculated using the NOAA-HYSPLIT model. Urinary 1-hydroxypyrene (1-OHP) levels were analyzed by HPLC. DNA damage, chromosomal instability and cell death were measured by a buccal micronucleus cytome assay (BMCyt). The PM concentrations for all measurements in the exposed area were higher than in the non-exposed area. SEM-EDS analyses exhibited a wide variety of particles, and K, Cl, S and Ca biomass burning tracers were the major inorganic compounds. In addition, atmospheric modeling analysis suggested that these particles can reach regions farther away than 40 kilometers. Occupational polycyclic aromatic hydrocarbon exposure was confirmed by increases in 1-OHP levels in cashew nut workers. Frequencies of BMCyt biomarkers of genotoxicity (micronuclei and nuclear bud) and cytotoxicity (pyknosis, karyolysis, karyorrhexis and condensed chromatin) were higher in the exposed group compared with the controls. The influence of factors, such as age, on the micronuclei frequencies was demonstrated, and a correlation between 1-OHP and micronuclei was observed. To the best of our knowledge, no other study has demonstrated a correlation between these types of biomarkers. The use of exposure (1-OHP) and effect (BMCyt) biomarkers were therefore efficient in assessing the occupational risk associated with artisanal cashew nut roasting, and the high rates of PM2.5 are considered to be a potential contributor to this effect.