Exposure to polycyclic aromatic hydrocarbons and genotoxic effects on nonsmoking Swedish road pavement workers.

OBJECTIVES: The objective of this study was to investigate exposure to polycyclic aromatic hydrocarbons (PAH) from asphalt fumes among Swedish road pavement workers and determine whether any effects could be detected with genotoxic tests. METHODS: The study included 28 nonsmoking road pavers and 30 nonsmoking referents. The concentration of PAH was determined in the breathing zone of the road pavers. 1-Hydroxypyrene was analyzed before and after shifts of asphalt work and during the afternoon for referents. Sister chromatid exchanges (SCE) and micronuclei (MN) were determined in peripheral lymphocytes. RESULTS: Several 3- or 4-ring PAH were found, and the analysis indicated that they occurred in bitumen fumes rather than in traffic fumes. The average total concentration of PAH was 2.3 (range 0.2-23.8) microg/m3. The concentration of 1-hydroxypyrene in urine was higher for the road pavers than for the referents, but there was no significant difference between the pre- and postshift values of the road pavers. The road pavers had no significant increase in SCE or MN. CONCLUSIONS: The study showed that Swedish road pavers have an increased exposure to PAH from bitumen fumes, but no genotoxic effects could be detected by SCE or MN tests.     

occupational exposure to aromatic hydrocarbons at a coke plant: Part II. Exposure assessment of volatile organic compounds

The objective of the study is to assess the external and internal exposures to aromatic hydrocarbons in the tar and oil naphthalene distillation processes at a coke plant. 69 workers engaged as operators in tar and oil naphthalene distillation processes and 25 non-exposed subjects were examined. Personal analyses of the benzene, toluene, xylene isomers, ethylbenzene, naphthalene, indan, indene and acenaphthene in the breathing zone air allowed us to determine the time weighted average exposure levels to the aromatic hydrocarbons listed above. The internal exposure was investigated by measurement of the urinary excretion of naphthols, 2-methylphenol and dimethylphenol isomers by means of gas chromatography with a flame ionization detection (GC/FID). Urine metabolites were extracted after enzymatic hydrolysis by solid-phase extraction with styrene-divinylbenzene resin. The time-weighted average concentrations of the hydrocarbons detected in the breathing zone air shows that the exposure levels of the workers are relatively low in comparison to the exposure limits. Statistically significant differences between average concentrations of aromatic hydrocarbons (benzene, toluene, xylene isomers) determined at the workplaces in the tar distillation department have been found. Concentrations of the naphthalene and acenaphthene detected in workers from the oil distillation department are higher that those from the tar distillation department. Concentrations of naphthols, 2-methoxyphenol and dimethylphenol isomers in the urine of occupationally exposed workers were significantly higher than those of non-exposed subjects. Concentrations of the 2-methoxyphenol and dimethylphenol isomers in urine were significantly higher for the tar distillation workers, whereas concentrations of naphthols were higher for the oil naphthalene distillation workers. Operators at the tar and naphthalene oil distillation processes are simultaneously exposed to a mixture of different hydrocarbons, mainly benzene and naphthalene homologues.     

General population exposure to volatile aromatic hydrocarbons

Aromatic hydrocarbons benzene, toluene, ethylbenzene, and isomeric xylenes (BTEX) are volatile organic compounds widespread in the biosphere because of their physical and chemical properties and their use. They are major constituents of gasoline, and vehicular traffic is the main source of BTEX in the environment. Significant additional exposure to BTEX results from tobacco smoking. General population is more or less permanently exposed to BTEX. This review summarises their distribution in the environment, analytical methods for BTEX determination in biological samples, and published data on BTEX concentrations in blood, exhaled air and urine samples of general population. The paper also describes toxic effects of BTEX on human health associated exclusively with professional exposure. Concentrations of these compounds in biological samples collected from general population reflect environmental pollution. Biological monitoring of people exposed to environmental BTEX concentrations is the first step toward evaluating health risk.     

Biomonitoring of genotoxic exposure of aluminium plant workers.

Humans are environmentally and occupationally exposed to polycyclic aromatic hydrocarbons (PAH). PAH's are a class of tumorigenic compounds which act through metabolic transformation to chemically reactive forms, epoxides, which covalently bind to DNA forming DNA adducts. To evaluate the genotoxic effects of PAH's, air and urine samples were analyzed for PAH. Blood samples were analyzed for benzo(a)pyrene-diol-epoxide-DNA (BPDE-DNA) adducts. New methods for analyzing DNA adducts in lymphocytes have been used to study the genotoxic effects of human exposure to carcinogens. BPDE-DNA adducts in lymphocytes have been used as internal dosimeters of exposure to PAH's and several studies have been conducted. We measured BPDE-DNA adducts in aluminium plant workers with immuno-assay and physico-chemical methods. PAH-DNA adducts were detectable to a lesser extent in subjects working in an aluminium plant compared to subjects working in a coke oven plant.     

Preventive measures reduce exposure to polycyclic aromatic hydrocarbons at a graphite electrode plant

OBJECTIVE: This study assessed the efficacy of preventive measures in a graphite electrode plant aimed at reducing occupational exposure to polycyclic aromatic hydrocarbons (PAHs). METHODS: Electrode workers (n = 146) answered a questionnaire and provided an end of shift urine sample. Urinary 1-hydroxypyrene (1-hpur), a biological marker of exposure to PAHs, was measured by high performance liquid chromatography coupled with: (a) fluorescence detection. 1- Hydroxypyrene concentrations were compared with the concentrations measured before implementing the preventive measures; and (b) those of a control group of 54 men not occupationally exposed to PAHs. RESULTS: After implementation of preventive measures, median concentrations 1- hpur were significantly reduced in some groups of workers: by -24%, - 37% and -30% in workers at the green electrode unit, one baking impregnation unit, and the laboratory, respectively. In workers at a second baking impregnation unit, in end product finishing and in the power station 1-hpur concentrations were unchanged. Urinary 1-hp concentrations were still significantly higher in each group of workers than in the control group (p < 0.001 for any comparison). Concentrations in the workers varied with the type of job, the highest values being found in workers engaged in the power station, in the two baking impregnation units and in the green electrode unit. CONCLUSIONS: Implementing preventive measures significantly reduced exposure to PAHs at a graphite electrode plant. The reduction in median and peak concentrations of 1-hpur, which reflects total exposure to, and internal dose of PAHs, was most evident in workers employed in the units where preventive measures had been taken. Despite an overall reduction, further preventive measures are needed to minimise exposure to PAHs and consequently the risk of adverse health effects.

 

     

Neuropsychiatric effects of low exposure to styrene.

Workers exposed to styrene concentrations of about 50 mg/m3 at a plant manufacturing reinforced polyester boats were examined for neuropsychiatric symptoms both in close connection with exposure and also seven months after exposure had ceased. Physical workload is important for the uptake of styrene and was about 50 W at this plant. On the first occasion, after one week with no exposure, the workers reported a high frequency of neuropsychiatric symptoms such as fatigue, irritation, and forgetfulness whereas seven months later the frequency of these symptoms was low. These observations indicate that exposure to styrene at about 50 mg/m3 may induce reversible neuraesthenic symptoms. Even the relatively low Swedish standard (110 mg/m3 = 25 ppm) may, therefore, need revising.     

Dermal exposure to polycyclic aromatic hydrocarbons among primary aluminium workers.

Large amounts of PAH's are released in the electrode production departments of pre-bake cell aluminium reduction plants. Emission sources are mixing, shaping and baking of the anode (paste plant and bake oven) and pot relining operations. A study was performed to quantify the importance of dermal uptake of PAH's among exposed workers. Twenty workers in the anode production departments (paste plant (N = 8) and bake oven (N = 5)) and the pot relining department (N = 7) volunteered for the study. Monitoring was performed over a period of 5 consecutive days using personal air sampling, dermal contamination sampling and biological monitoring. Pyrene concentrations measured in the respirable air samples, ranged up to 320 micrograms/m3. Dermal contamination of pyrene was monitored at three skin sites (wrist, jaw/neck and groin) using exposure pads as pseudo-skin. The skin contamination with pyrene ranged up to 375 ng/cm2. Contamination of the groin skin site, although covered by work clothes ranged up to 106 ng/cm2. The concentration of 1-hydroxypyrene in pre and post-shift urine ranged up to 27 mumol/mol creatinine and showed an increase during the day and a decrease during the night. Pyrene in air and pyrene on the skin were tested for significance of correlation with urinary 1-hydroxypyrene in samples taken at several moments: end-of-shift, pre-shift next morning and weekly increase. The correlation coefficients between dermal contamination and urinary 1-hydroxypyrene were equal or higher than the correlation coefficient between pyrene air concentration and urinary 1-hydroxypyrene. The total skin contamination in exposed workers is estimated to be more than three times higher than the intake via the respiratory tract. The contribution of dermal exposure to the total PAH body burden of exposed workers therefore appears to be significant.     

Neuropsychiatric effects of low exposure to styrene

Workers exposed to styrene concentrations of about 50 mg/m3 at a plant manufacturing reinforced polyester boats were examined for neuropsychiatric symptoms both in close connection with exposure and also seven months after exposure had ceased. Physical workload is important for the uptake of styrene and was about 50 W at this plant. On the first occasion, after one week with no exposure, the workers reported a high frequency of neuropsychiatric symptoms such as fatigue, irritation, and forgetfulness whereas seven months later the frequency of these symptoms was low. These observations indicate that exposure to styrene at about 50 mg/m3 may induce reversible neuraesthenic symptoms. Even the relatively low Swedish standard (110 mg/m3 = 25 ppm) may, therefore, need revising.     

Risk assessment of inhalation exposure to polycyclic aromatic hydrocarbons in Taiwanese workers at night markets

Objective  

To examine the inhalation exposure of cooks at night markets in Taiwan to PAHs and to estimate the corresponding potential human health risks posed by the inhalation of carcinogenic PAHs.     

Monitoring of occupational exposure to polycyclic aromatic hydrocarbons in a carbon-electrode manufacturing plant

An investigation is presented of occupational exposure to polycyclic aromatic hydrocarbons (PAH) in a carbon-electrode manufacturing plant, as assessed by three monitoring methods, viz. environmental monitoring of the external dose by analysis of personal air samples, biological monitoring of the internal dose by analysis of urinary 1-hydroxypyrene (1-OHpyrene), and biological effect monitoring by dosimetry of PAH-DNA adducts in blood lymphocytes. On the basis of job conditions, workers at the plant were divided into three groups with presumed low, intermediate and high exposure to air-borne PAH, respectively. All air samples showed levels of total PAH below the current MAC-value in the Netherlands, which is 200 μg/m³, whereas the benzo[a]pyrene level was occasionally higher than the recommended concentration of 2 μg/m³. The values of 1-OHpyrene in urine from the intermediate and high exposure groups were significantly higher than those of the low exposure group, namely 3.6- and 8.2-fold, respectively. Clear external and internal exposure was thus demonstrated for workers of the high and intermediate exposure groups, but this did not result in a measurable effect at the DNA level in blood lymphocytes. Tobacco smoking, on the other hand, caused a significant increase of the levels of PAH-DNA adducts but did not affect 1-OHpyrene values. These data suggest that smoking is a more important risk factor for adverse health effects, i.e. cancer, than occupational exposure to PAH in this plant.     

Association of exposure to polycyclic aromatic hydrocarbons (estimated from job category) with concentration of 1-hydroxypyrene glucuronide in urine from workers at a steel plant.

OBJECTIVES--Increased risk of lung cancer has been associated with employment in the steel industry. This association is thought to be due in part to increased concentrations of polycyclic aromatic hydrocarbons (PAHs) in air found in this work environment. Measurement of PAH metabolites in human urine provides a means of assessing individual internal dose of PAHs. This study examined the relative contribution of occupation and smoking to urinary concentration of 1-hydroxypyrene glucuronide (1-OHPG) among a group of workers at a steel plant. METHODS--Concentrations of 1-OHPG in urine from 44 workers with jobs associated with increased air concentrations of PAHs and 40 workers with jobs with low or no exposure to PAHs were measured. 20 workers in each group were not current smokers. Urinary 1-OHPG was measured by synchronous fluorescence spectroscopy after immunoaffinity chromatography specific for PAH metabolites. RESULTS--Mean (SEM) urinary 1-OHPG concentration was 2.16 (0.42) pmol/ml urine among the 44 occupationally exposed workers compared with 0.38 (0.05) among the 40 workers with no or low exposure (P < 0.0001). Mean urinary 1-OHPG concentration was 1.82 (0.41) pmol/ml urine among the 44 current smokers compared with 0.75 (0.20) among the 40 non-smokers (P < 0.005). Mean 1-OHPG concentrations in non-smokers were 0.26 (n = 20), 0.70 (n = 15), and 2.84 pmol/ml urine (n = 5) for strata of exposure to PAHs (no or low, mid, and high) based on job category; the corresponding values in smokers were 0.55 (n = 20), 0.94 (n = 12), and 4.91 pmol/ml (n = 12), respectively. Multiple linear regression showed significant differences between subjects in different PAH exposure with increased concentrations of 1-OHPG in urine. Amounts of foods containing PAHs ingested by this group of workers were relatively low and did not contribute significantly to urinary 1-OHPG concentrations. CONCLUSIONS--These results indicate that 1-OHPG is a common urinary metabolite in people with recent occupational exposure to PAHs and is associated with both job category and estimated stratum of PAH exposure.     

焦炉工职业性多环芳烃暴露特征的研究

目的 探讨焦炉工职业性多环芳烃暴露特征。方法 个体采样、高效液相色谱法测定作业环境中多环芳烃含量,以分析焦炉工职业暴露特征,并引入毒性当量因子概念,评价焦炉工职业性多环芳烃暴露的致癌潜能。结果 焦化厂炉顶工多环芳烃职业暴露水平明显高于炉侧工和炉底工,差异有统计学意义(P<0.05);焦炉工多环芳烃职业暴露中非致癌性物质所占比例>70％,致癌性物质中苯并(a)芘(B[a]Py)占总B[a]Py等当量浓度的65.5％-72.4％;多环芳烃职业暴露总量和B[a]Py及芘含量呈正相关(r2分别为0.84和0.94,P<0.05)。结论 焦炉工职业性多环芳烃暴露水平较高且具有一定的致癌潜能,致癌性物质以B[a]Py为主。     

Smoking modify the effects of polycyclic aromatic hydrocarbons exposure on oxidative damage to DNA in coke oven workers

Purpose

Coke oven emissions containing polycyclic aromatic hydrocarbons (PAHs) are predominant toxic constituents of particulate air pollution that have been linked to increased risk of lung cancer. Numerous epidemiological studies have suggested that oxidative DNA damage may play a pivotal role in the carcinogenic mechanism of lung cancer. Little is known about the effect of interaction between PAHs exposure and lifestyle on DNA oxidative damage.

Methods

The study population is composed by coke oven workers (365) and water treatment workers (144), and their urinary levels of four PAH metabolites and 8-hydroxydeoxyguanosine (8-OHdG) were determined. Airborne samples of exposed sites (4) and control sites (3) were collected, and eight carcinogenic PAHs were detected by high-performance liquid chromatography.

Results

The median values of the sum of eight carcinogenic PAHs and BaP in exposed sites were significantly higher than control sites (P?<?0.01). The study found that the urinary PAH metabolites were significantly elevated in coke oven workers (P?<?0.01). Multivariate logistic regression analysis revealed that the risk of high levels of urinary 8-OHdG will increase with increasing age, cigarette consumption, and levels of urinary 1-hydroxypyrene, and P for trend were all <0.05. Smoking can significantly modify the effects of urinary 1-hydroxypyrene on high concentrations urinary 8-OHdG, during co-exposure to both light or heavy smoking and high 1-hydroxypyrene levels (OR 4.28, 95% CI 1.32–13.86 and OR 5.05, 95% CI 1.63–15.67, respectively).

Conclusions

Our findings quantitatively demonstrate that workers exposed to coke oven fumes and smoking will cause more serious DNA oxidative damage.

     

重庆市某区小学女生多环芳烃内暴露水平及其与青春发动时相的关系

目的建立同时测定尿中4种多环芳烃(PAHs)代谢物的检测方法,研究重庆市某区女童青春发动时相提前与体内多环芳烃暴露水平的关系。方法研究对象采用目的性抽样,对重庆市某区4所小学1~4年级女生进行一般情况的问卷调查、生长发育的体格检查、并收集尿液,采用高效液相色谱-质谱联用法(HPLC-MS)对样品中4种PAHs代谢物进行定性和定量检测。结果 4种PAHs代谢物标准曲线相关性高,方法检出限为0.1 ng/mL。研究共调查女童737名,青春发动时相提前组209人,正常组528人。尿液检测结果显示4种PAHs代谢物检出率为100%,4种代谢物的检出浓度范围分别为1-羟基芘0.01~4.77 ng/mL,2-羟基萘0.15~50.00ng/mL,2-羟基芴0.06~12.59 ng/mL及9-羟基菲0.29~23.17 ng/mL。青春发动时相提前组和正常组在2-羟基芴(Z=-1.996)和9-羟基菲(Z=-3.161)暴露水平上差异具有统计学意义(P<0.05),控制了肥胖因素后,青春发动时相提前组9-羟基菲(Z=-3.012)暴露水平仍高于正常组(P<0.05)。结论该方法适用于4种PAHs代谢物的同时检测,研究地区女童青春发育早期均有PAHs暴露,且PAHs暴露可能是女童青春发动时相提前的因素之一。     

Polycyclic aromatic hydrocarbons in the work atmosphere. II. Determination in a coke plant

The content of polycyclic aromatic hydrocarbons (PAH) in the work atmosphere of a coke plant was investigated on two occasions. Stationary, mobile, and personal sampling were used, and the samples were analyzed by glass capillary gas chromatography. Up to 39 PAH and heterocyclic compounds were indentified in the samples. By personal sampling, the occupational exposure to PAH was determined to vary between 5 and 1,000 mg/m3. A study of the occurrence of PAH on particulate matter revealed that 98% of the PAH was respirable. No significant variation in the relative distribution of the PAH components (PAH profile) was observed during the two sampling periods. The PAH profile for the coke plant was similar to that of a S?derberg aluminum plant, but different from that of a S?derberg paste plant.     

Airborne exposure to polycyclic aromatic hydrocarbons (PAHs) and urinary excretion of 1-hydroxypyrene of carbon anode plant workers

Workers in plants producing carbon anodes for aluminium electrolysis are exposed to PAHs containing coal tar pitch volatiles, pitch and coke. The aim of this study was to evaluate the suitability of urinary 1-hydroxypyrene to characterize respiratory exposure to PAH, which is most relevant for assessing individual health risks. Six workers in a carbon anode plant volunteered to take part in a personal air sampling and a biological monitoring programme lasting five consecutive 8-h shifts to determine occupational exposure to airborne PAHs and urinary excretion of 1-hydroxypyrene. Exposure to total PAH for all worksites varied from 3.99 to 120.6 μg PAH m⁻³ and for benzo(a)pyrene (BaP) from 0.17 to 4.88 μg BaP m⁻³. The concentration of 1-hydroxypyrene in post- and pre-shift urine samples was in the range (0.5–61.8 μmol 1-OHP per mol creatinine) and depended on the worksite. The Spearman rank correlation test showed a low but significant (P < 0.05) correlation of urinary 1-hydroxypyrene in the post- and pre-shift samples with respiratory pyrene exposure. The quantitative aspects of biological monitoring for the evaluation of respiratory PAH exposure were tested with a pharmacokinetic model. On the basis of individual pyrene exposure, excretion of urinary 1-hydroxypyrene during the working week was calculated for each worker. The results presented in this investigation indicate that biological monitoring of the pyrene metabolite 1-hydroxypyrene is a useful indicator of a general PAH exposure, but cannot replace personal air sampling for assessing the lung cancer risk of individuals.     

No acute behavioural effects of exposure to styrene: a safe level of exposure?

To determine whether exposure to low levels of styrene (below 110 mg/m3) causes acute behavioural effects and symptoms that may be related to concentrations of styrene in air or urinary mandelic acid or both, 12 men occupationally exposed to styrene were studied and compared with a reference group of 10 unexposed men. Simple reaction time was measured before and after work and information about symptoms was obtained by questionnaire. Active and passive sampling of airborne styrene was carried out and urinary mandelic acid concentrations were measured. Although the size of the study groups is small, the results indicate that exposure to styrene below 110 mg/m3 does not cause any acute adverse effects on the central nervous system.     

No acute behavioural effects of exposure to styrene: a safe level of exposure?

To determine whether exposure to low levels of styrene (below 110 mg/m3) causes acute behavioural effects and symptoms that may be related to concentrations of styrene in air or urinary mandelic acid or both, 12 men occupationally exposed to styrene were studied and compared with a reference group of 10 unexposed men. Simple reaction time was measured before and after work and information about symptoms was obtained by questionnaire. Active and passive sampling of airborne styrene was carried out and urinary mandelic acid concentrations were measured. Although the size of the study groups is small, the results indicate that exposure to styrene below 110 mg/m3 does not cause any acute adverse effects on the central nervous system.