Solvent pollution in shoe factories]

In order to study solvent exposure in shoe factories, 43 kinds of glues and 22 solvent products used in footwear manufacturing were analyzed. A gas chromatographic spectrometric method was used to identify the mixtures of solvents contained in glues and their diluents. Acetone, ethylacetate and cyclohexane were the solvents more frequently found in glues. Cyclohexane represented on average about 40% of the solvent mixture. Methyl ethyl ketone, 3-methylpentane and 2-methylpentane were often present in glues (45-52% of the samples), but only in a few cases were they associated with n-hexane. N-hexane and methylcyclopentane were found in 32% of the glue samples. N-hexane represented 47% of the solvents only in one glue. Most of the glues contained less than 10% n-hexane. Other solvents (dichloropropane, toluene, trichloroethane, butyl acetate, iso-butyl acetate and 2,2-dimethylbutane) were found in few glue samples or in low percentages. The 22 solvents used as glue diluents were mainly acetone, ethylacetate, dichloromethane and methyl ethyl ketone. The results suggest that solvent exposure in shoe factories has changed compared with data reported about 10 years ago. Biological monitoring of shoe factory workers should measure exposures to the specific solvents found in each factory, especially acetone, cyclohexane, ethylacetate and methyl ethyl ketone.     

Sister chromatid exchanges and micronuclei in peripheral lymphocytes of shoe factory workers exposed to solvents

We examined sister chromatid exchanges (SCEs) and micronuclei (MN; cytokinesis-block method) in cultured peripheral lymphocytes from 52 female workers of two shoe factories and from 36 unexposed age- and sex-matched referents. The factory workers showed an elevated level of urinary hippuric acid, a biomarker of toluene exposure, and workplace air contained high concentrations of various organic solvents such as toluene, gasoline, acetone, and (in one of the plants only) ethylacetate and methylenediphenyl diisocyanate. The shoe factory workers showed a statistically significant higher frequency of micronucleated binucleate lymphocytes in comparison with the referents. This finding agreed with three preliminary MN determinations (each comprising 27-32 shoe workers and 16-20 controls) performed in one of the plants 2-5 years earlier. The shoe factory workers also had a lower average level of blood hemoglobin than the referents. In contrast, no difference was found between the groups in SCE analysis. Smokers showed significantly higher mean frequencies of SCEs per cell and high frequency cells (HFC) than nonsmokers. Aging was associated with increased MN rates and reduced cell proliferation. Polymorphism of the glutathione S-transferase M1 gene (GSTM1) did not affect the individual level of SCEs; but in smoking shoe workers an effect of the occupational exposure on the frequency of micronucleated cells could be seen only in GSTM1 null subjects. The low prevalence of the glutathione S-transferase T1 (GSTT1) null genotype precluded the evaluation of the influence of GSTT1 polymorphism. Our results show that the shoe factory workers have experienced genotoxic exposure, which is manifest as an increase in the frequency of MN, but not of SCEs, in peripheral lymphocytes. The exposures responsible for the MN induction could not be identified with certainty, but exposure to benzene in gasoline and methylenediphenyl diisocyanate may explain some of the findings.     

Cohort study among workers exposed to benzene in China: II. Exposure assessment

This report describes a retrospective exposure assessment method used in a follow-up mortality study of workers exposed to benzene. The approach quantified historical exposure to benzene in a multi-industry, multicenter cohort, involving 672 factories in 12 cities in China. Historical exposure data were collected to obtain exposure information related to 1,427 work units (departments) and 3,179 unique job titles from benzene-producing or -using factories in which written records and other data sources were evaluated. The basic unit for exposure assessment was a factory/work unit/job title combination which was considered separately during each of seven calendar-year time periods between 1949 and 1987 for a total of 18,435 exposure assignments. Historical information collected to estimate exposure included benzene monitoring data; lists of raw materials and factory products, and the percentage of benzene in each; the total amount and dates of use of benzene or benzene-containing materials; use of engineering controls and personal protective equipment; and other available exposure information. Overall, 38% (ranging from 3% for the earliest periods to 67% for the last period) of the estimates were based primarily on benzene monitoring data. In the absence of job-specific benzene monitoring data for a given calendar period, measurement results or exposure estimates for similar jobs and/or other calendar periods were used in conjunction with other exposure information to derive estimates. Estimated exposure levels are presented by industries and occupations. The highest average exposures during 1949–1987 were observed for the rubber and plastic industry (30.7 ppm), and for rubber glue applicators (52.6 ppm).     

制鞋厂工人健康危害现况研究

目的:调查某制鞋厂存在的职业危害现况,了解鞋厂职业危害因素对作业工人健康的影响,为采取有效防控措施提供科学依据。方法:对制鞋厂进行卫生学调查,对作业工人进行职业健康检查。结果:鞋厂车间空气监测结果超标率:苯16.1%,甲苯12.5%,1,2-二氯乙烷68.0%,鞋用粘胶剂超标率:苯7.7%,甲苯 二甲苯50%。作业工人健康检查结果:作业工人WBC异常率、RBC异常率以及HGB异常率较高,不同性别RBC异常率与HGB异常率有显著性差异。结论:鞋厂存在苯、甲苯、二甲苯、1,2-二氯乙烷、正己烷等多种职业危害因素。应加强对粘胶剂的源头控制和鞋厂作业场所的预防控制,减少对作业工人的健康损害。     

Occupational exposure to benzene in the shoe industry

In order to determine the possible actual exposure to benzene in the shoe industry from industrially used solvents, glues, and paints containing benzene as a nondeclared constituent, phenol in urine and benzene in blood, as indices of internal exposure to benzene, were measured in workers (N = 33). Since toluene, in contrast to benzene, is declared as a constituent in several glues, toluene in the blood of workers was also analysed. All analyses were performed using gas chromatography. Urine samples were collected on Monday morning (MI) before work and on Wednesday (WI) before and (WII) after work. Venous blood samples were taken on Wednesday only, 1/2 hour after work. There was no difference in the phenol concentrations of MI and WI, while the phenol concentration of WII was about twice as high as that in WI. In all blood samples, benzene was found, as well as toluene, which was about four times higher in comparison with benzene. A correlation (r = 0.465; p less than .01) was found between the difference in pre- and postshift phenol concentrations (WII-WI) in urine and the benzene concentrations in blood. The results presented show that a trace amount of benzene, which is often not declared as a constitutent in industrially used chemicals, could be a source of marked exposure to benzene. It can also be concluded that changes in phenol in urine (if preshift and postshift samples are taken) might be a sufficiently sensitive parameter to assess exposure to benzene even when other data concerning the presence of benzene in the working atmosphere are not available.     

福建省常用无"三苯"鞋用胶水和溶剂的急性毒性研究

目的：了解无“三苯”鞋用胶水和溶剂的急性毒性。方法：采用急性吸入毒性试验,急性眼刺激试验,急性皮肤刺激试验和皮肤过敏试验进行急性毒性研究。结果：各样品的急性毒性均为低毒,有3份样品对家兔眼粘膜有轻刺激性,6份样品对皮肤刺激作用表现为轻刺激,其余均为无刺激性,对豚鼠皮肤除1份样品为轻度致敏外,其余均表现为弱致敏作用。结论：目前使用的无“三苯”鞋用胶水和溶剂为低毒类。     

低苯暴露人群尿中t，t-MA及S-PMA的生物监测

目的分析职业低苯和环境低苯接触与人体尿液中t,t-MA和S-PMA浓度的相关性。方法选取广州市某制鞋厂钳帮和刷胶工人等苯职业接触人员作为职业低苯暴露人群（职业组）,选取非职业苯接触且家庭1年内装修过并已入住半年以上的人员作为环境低苯接触人群（环境组）。采用超高效液相串联质谱联用（UPLC—MS／MS）内标法测定尿中t,t-反式粘糠酸（t,t-MA）及苯巯基尿酸（S-PMA）含量,采用气相色谱法检测空气中苯浓度。结果职业组个体空气暴露的苯浓度（均值±标准差）为（0．16±0．06）mg／m^3,尿中t,t-MA及S-PMA含量分别为（42．7±39．2）和（0．28±0．19）μg／gCr;环境组个体空气暴露的苯浓度中位数（四分位间距）为0．01（0．02）mg／m^3,尿中t,t-MA及S-PMA含量的中位数（四分位间距）分别为20．5（16．2）和0．03（0．04）μg/gCr;经非参数Mann—WhitneyU—test检验分析发现：职业组的个体空气暴露苯浓度及尿中t,t-MA、S-PMA含量均高于环境组（均P〈0．01）。相关性分析结果显示,当空气中苯浓度为0．16mg／m^3时,尿中t,t—MA和S-PMA与空气中苯浓度存在良好的相关性（r=0．499、0．715）。结论t,t-MA及S-PMA可作为生物标记物用于职业低苯和环境低苯暴露的生物监测。     

Solvent exposures at shoe factories and workshops in Hebron City, West Bank

Exposure to organic solvents has been reported to increase the risks for acute and chronic health effects among shoe industry workers. In developing countries, protection against chemical exposures is often not provided. The study was conducted to identify working conditions and estimate the concentrations of organic solvents used in shoe factories and workshops in Hebron City. Personal interviews containing questions related to personal protective equipment (PPE) were used to identify working conditions, and samples collected from factories and workshops were analyzed using gas chromatography. Geometric means (GMs) were calculated for the solvents. Six major organic solvents were detected in the factories. Acetone (GM = 51.5 mg/m3, GSD = 3.82) was common in gluing tasks. Dichloromethane (GM = 47 mg/m3, GSD = 2.62) was common in cleaning tasks. Heptane, methylethyl ketone, n-hexane, and toluene were common in gluing tasks. Four major organic solvents were detected in the workshops: acetone (GM = 32.3 mg/m:3, GSD = 6.33), toluene (GM = 70.3 mg/m3, GSD = 3.06), n-hexane (GM = 19.4 mg/m3:, GSD = 2.65), and methylethyl ketone (GM = 130 mg/mM3, GSD = 1.5). 81% of the factory workers had never used respiratory protective equipment, and 92% had never used work clothes. 97% of the workers in the workshops had never used respiratory protective equipment, 94% had never worn gloves, and 90% had never used work clothes. Exposures to solvents in the absence of personal Protective equipment, tasks barriers, and mechanical ventilation can adversely affect health.     

Dermal exposure assessment to benzene and toluene using charcoal cloth pads

Charcoal cloth pads have been used to assess volatile chemicals on the skin in a laboratory setting; however, they have not yet been applied to measure dermal exposure in occupational settings. This study aimed at evaluating whether charcoal pads can be used to assess dermal exposure to benzene and toluene in workers of a petrochemical plant. Inhalation and dermal exposure levels to benzene and toluene were assessed for workers of a petrochemical plant performing different jobs. Benzene uptake was assessed by determining S-phenylmercapturic acid in workers' urine samples. Dermal exposure levels on the charcoal pads were adjusted for ambient air levels of benzene and toluene by subtracting the amount of benzene or toluene measured in personal air from the amount of benzene or toluene measured on the charcoal pad. In general, measured external and internal exposure levels were low. The estimated contribution of the dermal route to internal benzene exposure levels was less than 0.06% for all jobs. Toluene personal air concentrations and benzene and toluene dermal exposure levels differed statistically significantly between job titles. For benzene, differences between jobs were larger for adjusted dermal exposures (maximum 17-fold, P = 0.02) than for inhalation exposures (maximum two-fold, P = 0.08). Also for toluene, although less clear, differences between jobs were larger for adjusted dermal exposures (maximum 23-fold, P = 0.01) as compared to inhalation exposures (maximum 10-fold, P = 0.01). Charcoal pads appeared to measure dermal exposures to benzene and toluene in addition to ambient air levels. Future studies applying charcoal cloth pads for the dermal exposure assessment at workplaces with higher dermal exposure to organic solvents may provide more insight into the biological relevance of dermal exposure levels measured by charcoal cloth pads. In addition, the design of the dermal sampler might be improved by configuring a dermal sampler, where part of the sampler is protected against direct contact and splashes, but still permeable for the gas phase. This design would most likely result in a better ability to correct for airborne concentrations at a given body location.     

Solvent Exposures at Shoe Factories and Workshops in Hebron City,West Bank

Abstract

Exposure to organic solvents has been reported to increase the risks for acute and chronic health effects among shoe industry workers. In developing countries, protection against chemical exposures is often not provided. The study was conducted to identify working conditions and estimate the concentrations of organic solvents used in shoe factories and workshops in Hebron City. Personal interviews containing questions related to personal protective equipment (PPE) were used to identify working conditions, and samples collected from factories and workshops were analyzed using gas chromatography. Geometric means (GMs) were calculated for the solvents. Six major organic solvents were detected in the factories. Acetone (GM = 51.5 mg/m³, GSD = 3.82) was common in gluing tasks. Dichloromethane (GM = 47 mg/m³, GSD = 2.62) was common in cleaning tasks. Heptane, methylethyl ketone, n-hexane, and toluene were common in gluing tasks. Four major organic solvents were detected in the workshops: acetone (GM = 32.3 mg/m³, GSD = 6.33), toluene (GM = 70.3 mg/m³, GSD = 3.06), nhexane (GM = 19.4 mg/m³, GSD = 2.65), and methylethyl ketone (GM = 130 mg/m³, GSD = 1.5). 81% of the factory workers had never used respiratory protective equipment, and 92% had never used work clothes. 97% of the workers in the workshops had never used respiratory protective equipment, 94% had never worn gloves, and 90% had never used work clothes. Exposures to solvents in the absence of personal Protective equipment, tasks barriers, and mechanical ventilation can adversely affect health.     

Shoe-makers'' polyneuropathy in Italy: the aetiological problem.

Since 1957, when the first cases of the so-called shoe-makers' toxic polyneuropathy were reported, nearly 400 cases have been described in the Italian literature. The substance that was considered to be responsible for the disease was triorthocresylphosphate (TOCP) contained in glues, artificial leathers, and some types of paints. However numerous chemical analyses of glues and leathers taken from factories where cases of the disease occurred have shown that in almost all instances little or no TOCP was present. In addition the disease manifests itself more frequently during winter and spring and this is not consistent with the absorption of the causative agent through the skin and/or gastrointestinal tract. In order to clarify the aetiology of the disease 122 workers in the shoe industry affected by toxic polymeuropathy during the period 1971-74 were studied. Workplaces where cases of polyneuropathy had occurred were visited and samples of glues and solvents were taken for chemical analysis. The polyneuropathy chiefly affects workers engaged in glueing and in the cleaning process, but it also affects those who do not have direct contact with glues or solvents. The disease is more common in women (68%) than in men (32%) and, in its more severe form begins with overwhelming prevalence during winter and early spring regardless of the job performed. No direct relationship has been found between the severity of the disease and the number of years of work in the shoe industry or of specific exposure (that is the number of years of work in the activity performed at the onset of the disease). The polyneuropathy is found almost exclusively among workers of the artisam type in small shoe factories, where standards of hygiene are low. Chemical analysis of glues and cleaning fluids collected from five different factories, where 20 cases of polyneuropathy occurred, showed the presence of paraffin hydrocarbons with a low boiling point (pentane, 2-methyl-pentane, 3-methyl-pentane, n-hexane, etc.) in concentrations of more than 80% by weight.     

Shoe-makers' polyneuropathy in Italy: the aetiological problem.

Since 1957, when the first cases of the so-called shoe-makers' toxic polyneuropathy were reported, nearly 400 cases have been described in the Italian literature. The substance that was considered to be responsible for the disease was triorthocresylphosphate (TOCP) contained in glues, artificial leathers, and some types of paints. However numerous chemical analyses of glues and leathers taken from factories where cases of the disease occurred have shown that in almost all instances little or no TOCP was present. In addition the disease manifests itself more frequently during winter and spring and this is not consistent with the absorption of the causative agent through the skin and/or gastrointestinal tract. In order to clarify the aetiology of the disease 122 workers in the shoe industry affected by toxic polymeuropathy during the period 1971-74 were studied. Workplaces where cases of polyneuropathy had occurred were visited and samples of glues and solvents were taken for chemical analysis. The polyneuropathy chiefly affects workers engaged in glueing and in the cleaning process, but it also affects those who do not have direct contact with glues or solvents. The disease is more common in women (68%) than in men (32%) and, in its more severe form begins with overwhelming prevalence during winter and early spring regardless of the job performed. No direct relationship has been found between the severity of the disease and the number of years of work in the shoe industry or of specific exposure (that is the number of years of work in the activity performed at the onset of the disease). The polyneuropathy is found almost exclusively among workers of the artisam type in small shoe factories, where standards of hygiene are low. Chemical analysis of glues and cleaning fluids collected from five different factories, where 20 cases of polyneuropathy occurred, showed the presence of paraffin hydrocarbons with a low boiling point (pentane, 2-methyl-pentane, 3-methyl-pentane, n-hexane, etc.) in concentrations of more than 80% by weight.     

某鞋厂347例接触混合有机溶剂作业工人肝脏B超检查结果分析

目的 探讨长期低浓度接触混合有机溶剂对制鞋作业工人肝脏的影响。 方法 对生产车间使用甲苯、苯、二氯乙烷、正己烷等混合有机溶剂的某鞋业工厂347名工人(接触组)和工厂无毒物接触史后勤人员321人(对照组)进行肝脏B超检查,比较两组检查结果。 结果 生产车间使用的有机溶剂的时间加权平均浓度均未超过职业接触限值。接触组弥漫性肝回声音改变、肝大的检出率均高于对照组,上述指标在两组间比较,差异均有统计学意义(χ2=27.8、12.5,P<0.05)。将两组各分成6个工龄段,弥漫性肝回声改变的检出率在工龄大于等于2年(4个工龄段)的两组员工间比较,差异均有统计学意义(χ2=8.9、10.2、10.2、10.5,P<0.05),两组的异常检出率均随着工龄的增加而升高。 结论 较长时间接触混合有机溶剂对作业工人肝脏可能存在慢性损害,应注意预防。     

Exposure to acid anhydrides in three resin and one cushioned flooring manufacturing plants

Acid anhydrides are reactive organic chemicals of low molecular weight which cause occupational asthma. No previous research on the relationship between exposure to these chemicals and respiratory sensitization and development of occupational asthma has been reported. A retrospective cohort study was carried out in four factories (three alkyd resin factories and one cushioned flooring factory) to investigate the nature of exposure-response relationships for sensitization to phthalic anhydride (PA), trimellitic anhydride (TMA) and maleic anhydride (MA). This paper describes the results of full-shift and task-specific exposure measurements. Exposure to PA was low in relation to the Occupational Exposure Standard (OES). The highest full-shift PA exposures occurred among resin operators in the resin factory that used solid PA as compared to other resin factories where liquid PA was used. Arithmetic mean exposure levels to TMA and MA in the resin factories were well below their respective OESs. Short-term high exposures occurred during loading of acid anhydrides into the reactors and sampling and testing of the resin. Relatively high full-shift exposure to TMA occurred in the cushioned flooring factory, although no high peak exposures were detected.     

Environmental and biological monitoring of benzene during self-service automobile refueling

Although automobile refueling represents the major source of benzene exposure among the nonsmoking public, few data are available regarding such exposures and the associated uptake of benzene. We repeatedly measured benzene exposure and uptake (via benzene in exhaled breath) among 39 self-service customers using self-administered monitoring, a technique rarely used to obtain measurements from the general public (130 sets of measurements were obtained). Benzene exposures averaged 2.9 mg/m(3) (SD = 5.8 mg/m(3); median duration = 3 min) with a range of < 0.076-36 mg/m(3), and postexposure breath levels averaged 160 microg/m(3) (SD = 260 microg/m(3)) with a range of < 3.2-1,400 microg/m(3). Log-transformed exposures and breath levels were significantly correlated (r = 0.77, p < 0.0001). We used mixed-effects statistical models to gauge the relative influences of environmental and subject-specific factors on benzene exposure and breath levels and to investigate the importance of various covariates obtained by questionnaire. Model fitting yielded three significant predictors of benzene exposure, namely, fuel octane grade (p = 0.0011), duration of exposure (p = 0.0054), and season of the year (p = 0.032). Likewise, another model yielded three significant predictors of benzene concentration in breath, specifically, benzene exposure (p = 0.0001), preexposure breath concentration (p = 0.0008), and duration of exposure (p = 0.038). Variability in benzene concentrations was remarkable, with 95% of the estimated values falling within a 274-fold range, and was comprised entirely of the within-person component of variance (representing exposures of the same subject at different times of refueling). The corresponding range for benzene concentrations in breath was 41-fold and was comprised primarily of the within-person variance component (74% of the total variance). Our results indicate that environmental rather than interindividual differences are primarily responsible for benzene exposure and uptake during automobile refueling. The study also demonstrates that self-administered monitoring can be efficiently used to measure environmental exposures and biomarkers among the general public.     

苯作业工人淋巴细胞p53相关基因mRNA表达水平分析

目的 了解苯环境作业工人外周血淋巴细胞中,经p53介导的DNA损伤修复路径相关基因表达水平.方法 选择某喷涂厂直接接苯工人46人(直接接苯组)、间接接苯工人26人(间接接苯组)和无苯及其他毒物接触工人29人(对照组),应用SYBR GreenI嵌合荧光法实时RT-PCR分析技术,检测外周血淋巴细胞p53及相关基因mRNA表达水平,比较对照组与作业组问P53及相关基因mRNA表达倍数差异.结果 直接接苯组和间接接苯组p53、Ku80、Ape1和Mdm-2 mRNA表达水平与对照组比较磋异无统计学意义(P＞0.05);p21有增高趋势,但差异无统计学意义(P＞0.05).直接接苯组的Rad51、Bcl-2、Bax、Xpa和Xpc mRNA表达水平下调、间接接苯组Rad51 mRNA表达下调,与对照组比较,差异有统计学意义(P＜0.05或P＜0.01).直接接苯组的白细胞、血红蛋白和血小板分别为(4.93±1.27)×10- /L、(123.97+11.80)g/L和(124.02±41.22)×109 /L,间接接苯组血小板为(135.80±39.44)×109 /L,均低于对照组,差异均有统计学意义(P＜0.05或P＜0.01).结论 长期慢性的低浓度苯接触可使工人淋巴细胞中p53介导的部分DNA损伤修复相关基因mRNA表达水平发生改变,直接接苯工人的外周血白细胞、血红蛋白、血小板减低以及Bcl-2、Bax、Xpa和Xpc mRNA表达水平改变明显.     

Shoe manufacturing and solvent exposure in northern Portugal

Shoe manufacturing is a traditional industry in northern Portugal. There are nearly 1500 factories that employ about 54,000 workers. Among the materials used in the shoe manufacturing process, that could be occupational hazards, are the adhesives, especially adhesives solutions based on organic solvents. The National Institute of Health (Oporto Branch) carried out a study of 100 factories in northern Portugal to study solvent exposure in shoe manufacturing. The surveyed population, (4615 workers) was young (mean age = 33 years; range = 18-45) and predominantly female (68.5%). The results from the air samples analyses show 20 different organic compounds existing in the workplaces. The more common compounds found were n-hexane, toluene, and acetone. The results of the study show that in 53.7 percent of the factories there are operations where the solvent exposure is significant and represents a health hazard to the workers. These operations are mainly gluing, waxing, and polishing stations. Occupational risk of exposure to solvents concerned 44.2 percent of the workers. This study points out the existence of inadequate ventilation in the workplaces and inappropriate personal protective equipment to prevent dermatitis risk from adhesives, wax, and polish. The organic solvents present in workplaces also increase fire risk.     

Modeling, estimation and validation of cotton dust and endotoxin exposures in Chinese textile operations

In support of an epidemiological study of cancer incidence among cotton textile workers in Shanghai, PRC, historical estimates of exposure to cotton dust and endotoxin were developed for subjects drawn from a cohort of 267,400 female textile workers. A large dataset of historical cotton dust measurements were available from 56 of the study factories. Using these data, a series of models were developed to estimate cotton dust exposure by year, factory and process. Model estimates were validated by comparing with independently collected measurements gathered over a 15 year period and indicated a low relative bias (< 2%) and relative accuracy (+/- 61%). Endotoxin exposures were estimated using the endotoxin content of cotton dust by major processes obtained in five separate surveys in these factories. The validated exposures were assigned to the 7,242 jobs held by the 3,812 study subjects. Among the exposed workers, the mean cumulative exposure levels were 113.8 mg m(-3)*years for cotton dust and 6,707.7 EU m(-3)*years for endotoxin, respectively. The overall correlation among cotton dust and endotoxin exposures for these subjects was r = 0.58. Using an unusually rich set of historical cotton dust measurements, along with independently collected exposure measurements for validation and conversion to endotoxin levels, validated estimates of cumulative exposure were constructed for this large case-cohort study in the textile industry.     

Exposures to jet fuel and benzene during aircraft fuel tank repair in the U.S. Air Force

Jet fuel and benzene vapor exposures were measured during aircraft fuel tank entry and repair at twelve U.S. Air Force bases. Breathing zone samples were collected on the fuel workers who performed the repair. In addition, instantaneous samples were taken at various points during the procedures with SUMMA canisters and subsequent analysis by mass spectrometry. The highest eight-hour time-weighted average (TWA) fuel exposure found was 1304 mg/m3; the highest 15-minute short-term exposure was 10,295 mg/m3. The results indicate workers who repair fuel tanks containing explosion suppression foam have a significantly higher exposure to jet fuel as compared to workers who repair tanks without foam (p < 0.001). It is assumed these elevations result from the tendency for fuel, absorbed by the foam, to volatilize during the foam removal process. Fuel tanks that allow flow-through ventilation during repair resulted in lower exposures compared to those tanks that have only one access port and, as a result, cannot be ventilated efficiently. The instantaneous sampling results confirm that benzene exposures occur during fuel tank repair; levels up to 49.1 mg/m3 were found inside the tanks during the repairs. As with jet fuel, these elevated benzene concentrations were more likely to occur in foamed tanks. The high temperatures associated with fuel tank repair, along with the requirement to wear vapor-permeable cotton coveralls for fire reasons, could result in an increase in the benzene body burden of tank entrants.     

Increase in exhaled nitric oxide in shoe and leather workers at the end of the work-shift

BACKGROUND: Measurement of nitric oxide (NO) in exhaled air is a non-invasive procedure for assessing airway or pulmonary inflammation, and for evaluating environmental irritant effects of air pollution. The objective of this study was to evaluate exhaled NO levels in synthetic leather workers exposed to organic solvents toluene, xylene and methylethyl ketone. METHODS: Seventeen shoe and leather workers and 10 controls from administrative personnel of the factory were studied. The levels of exhaled NO at baseline and at the end of the work shift were measured using a standardized chemiluminescence technique. Environmental assay of the three solvents was also assessed during the working day. RESULTS: Environmental solvent concentrations were high but within permissible exposure levels. Exhaled NO concentrations increased by 40% in the leather workers at the end of the working day from a mean +/- SD of 9.1 +/- 1.3 p.p.b. to 12.8 +/- 1.7 p.p.b. (P < 0.02), as compared to the controls. CONCLUSION: Exhaled NO is increased in shoe and leather workers exposed to solvents at the end of work shift, while it does not change in unexposed subjects of the same factory. Exhaled NO may be a sensitive tool to monitor sub-clinical effects of occupational pro-inflammatory substances.