Mortality experience of employees exposed to 2-mercaptobenzothiazole at a chemical plant in Nitro, West Virginia.

Mortality trends for 1059 production workers at a rubber chemicals plant in Nitro, West Virginia were examined to find whether they had increased mortality from cancer associated with exposure to 2-mercaptobenzothiazole (MBT). This chemical and its derivatives are vulcanising agents that have been manufactured at the plant since 1935. Analyses were conducted on MBT exposed employees by cumulative exposure and time since first exposure, and were also stratified by past assignment to p-aminobiphenyl (PAB) related departments; PAB is a potent bladder carcinogen that was used at the plant between 1935 and 1955. There was an excess of bladder cancer in MBT workers who had PAB related assignments (standardised mortality ratio (SMR) = 3200, 95% confidence interval (95% CI) 1286-6593). In employees without a job assignment with exposure to PAB, there were no associations between exposure to MBT and increased rates of most malignant neoplasms. The SMR for bladder cancer was increased based on three deaths (SMR = 455, 95% CI 94-1328), although these results were too few to evaluate trends by cumulative exposure category. The possibility of confounding by PAB for exposures for jobs that covered all areas of the plant for these three cases must be considered in the light of the potency of PAB as a bladder carcinogen. There were no deaths from bladder cancer among MBT workers hired after the end of manufacture and use of PAB, but the expected number of deaths was only 0.03.     

Chronic psychological effects of exposure to mercury vapour among chlorine-alkali plant workers

BACKGROUND: Quantitative assessment of nervous system function is essential in characterising the nature and extent of impairment in individuals experiencing symptoms following work-place mercury vapour exposure. OBJECTIVES: The purpose of this study was the application of standardised tests of behavioural, psychomotor and memory function to understand the neuropsychological effects of mercury in occupationally exposed chlorine-alkali plant workers. SUBJECTS AND METHODS: The study comprised 45 workers at a chlorine-alkali plant with the mean age of 39.36 +/- 5.94 years, who had been exposed to daily inhalation of mercury vapour over long-term employment of 16.06 +/- 4.29 years. The cumulative mercury index was 155.32 +/- 95.02 micrograms/g creatinine, the mean of urinary mercury concentrations on the first day of the study was 119.50 +/- 157.24 micrograms/g creatinine, and the mean of urinary mercury concentrations 120 days after cessation of exposure was 21.70 +/- 26.07 micrograms/g creatinine. The analysis included tests of behavioural, psychomotor and memory function. The behavioural test battery consisted of: Environmental Worry Scale (EWS), Minnesota Modified Personal Inventory (MMPI-2), Purdue standard 25 minute test, and adapted, 10 minutes test, Bender's Visual-Motor Gestalt test (BGT), and Eysenck Personality Inventory (EPQ). The data were compared to a control group of 32 not directly exposed workers. RESULTS: In the mercury vapour exposed workers with relatively high level exposure to inorganic mercury vapour (TWA/TLV = 0.12 mg/m3/0.025 mg/m3) we identified somatic depression-hypochondria symptoms with higher scores for scales: hysteria (P < 0.001), schizoid and psycho-asthenia (MMPI-2). The mercury-exposed workers had introvert behaviour (EPQ, MMPI-2). The cognitive disturbances in mercury-exposed workers were identified as: concentration difficulty, psychomotor, perceptual and motor coordination disturbances, and brain effects. We identified fine tremor of the hands in 34 out of 45 mercury-exposed workers (BGT). CONCLUSIONS: The results point to a relationship between the duration of mercury exposure and the long-term, probably irreversible, psychological disturbances.     

某化工厂过氯酸铵粉尘作业工人健康状况调查

目的 了解过氯酸铵(AP)粉尘对作业工人健康的影响,为其预防措施提供依据.方法 选择该厂接触AP粉尘的36名作业工人为接触组,不接触AP粉尘的48名该厂工人为对照组.调查工厂的一般情况,监测作业场所的AP粉尘浓度,对两组人群进行职业健康体检,检测血常规、肝肾功能、甲状腺激素指标,进行肺通气功能和X线胸片检查.结果 AP总粉尘浓度以组批车间最高,为(51.63±43.27) mg/m3.接触组收缩压[(146.14±21.03)mmHg]明显高于对照组[(134.67±18.58)mmHg],差异有统计学意义(P＜0.05).接触组全身各系统症状(皮粗、皮痒、气短、咳嗽、咳痰、咽干、疲乏无力等)累计检出率、气短及皮痒的检出率分别为86.11％、30.56％、36.11％,均明显高于对照组(66.67％、12.50％、10.42％),差异均有统计学意义(P＜0.05).接触组的游离三碘甲状腺原氨酸(FT3)水平[(1.29±0.20) ng/ml]明显低于对照组[(1.41±0.23) ng/ml],差异有统计学意义(P＜0.01).接触组工人的1秒用力肺活量与用力肺活量百分比值(FEV1.0/FVC)低于对照组,但差异无统计学意义(P＞0.05).接触组检出1例肺部X线影像异常者,并诊断为尘肺,对照组检出1例左肺门区有1约1.0x1.0小结节影.结论 接触组工人的收缩压明显高于对照组,不排除与接触AP粉尘有关;接触组工人的FT3低于对照组,提示长期接触AP粉尘可能会对作业工人甲状腺功能造成影响.     

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.     

Biological and environmental monitoring of occupational exposure of pharmaceutical plant workers to methotrexate

Summary The exposure of 11 pharmaceutical plant workers to methotrexate (MTX) was studied. Personal air samples were taken during the different manufacturing processes: drug compounding, vial filling, and tablet preparation. The uptake of MTX was established by the determination of MTX in urine. MTX was analyzed using the fluorescence polarization immunoassay (FPIA), a method that is frequently used for monitoring serum levels in patients treated with MTX. The FPIA method was modified in such a way that MTX could be measured quickly and efficiently in air and urine samples. MTX was detected in air samples of all workers except for those involved in the vial filling process (range: 0.8–182 g/m³; median: 10 g/m³). The highest concentrations were observed for workers weighing MTX (118 and 182 g/m³). MTX was detected in urine samples of all workers. The mean cumulative MTX excretion over 72–96 h was 13.4 g MTX-equivalents (range: 6.1–24 g MTX-equiva g MTX-equivalents (range: 6.1–24 g MTX-equivalents). lents). A significantly lower background level of 10.2 g A significantly lower background level of 10.2 g MTX-equivalents was measured in urine of 30 control persons (range: 4.9–21 g MTX-equivalents).     

Monitoring risks in association with exposure levels among wastewater treatment plant workers

OBJECTIVE: To investigate the relationship between exposure to hydrogen sulfide and endotoxin during specific job tasks and health symptoms among wastewater treatment plant (WWTP) workers. METHODS: The exposure levels for specific tasks were measured by personal monitoring. The health symptoms of WWTP workers were compared with those of water treatment plant workers through a questionnaire survey. RESULTS: Exposure levels for all monitored tasks were less than 1 ppm for hydrogen sulfide and 91 EU/m (endotoxin units/m) for endotoxin. Statistically higher odds ratios of respiratory, ocular and skin irritation, neurology, and gastrointestine symptoms were shown among WWTP workers compared with water treatment plant workers. Tasks related to sludge handling and plant inspection showed statistically significant associations with memory/concentration difficulties, throat irritation, and stomach pain. CONCLUSIONS: These results suggest that exposure control programs for specific job tasks and work locations are needed.     

Determination of low level exposure to volatile aromatic hydrocarbons and genotoxic effects in workers at a styrene plant.

OBJECTIVES--Low exposures to volatile aromatic hydrocarbons and cytogenetic effects in peripheral white blood cells were determined in 25 healthy workers employed in different areas of a styrene production plant in the former German Democratic Republic. The results were compared with 25 healthy unexposed controls (matched for age and sex) employed in the same company. METHODS--The concentrations of aromatic hydrocarbons determined from active air sampling in all areas of the factory (styrene: 73-3540 micrograms/m3 (< 0.01-0.83 ppm); ethylbenzene 365-2340 micrograms/m3 (0.08-0.53 ppm); benzene 73-3540 micrograms/m3 ( < 0.02-1.11 ppm); toluene 54-2960 micrograms/m3 (0.01-0.78 ppm); xylenes 12-94 micrograms/m3 ( < 0.01-0.02 ppm)) were considerably lower than in the pump house ( > 4000 micrograms/m3 styrene, ethylbenzene, benzene, and toluene; > 500 micrograms/m3 xylenes), which was only intermittently occupied for short periods. Passive personal monitoring, biomonitoring of exhaled air and metabolites (mandelic, phenylglyoxylic, trans, trans-muconic, hippuric, o-, m- and p-methylhippuric acids, and phenol) in urine samples collected before and after an eight hour working shift was used to assess individual exposure. Questionnaires and examination of company records showed that the historical exposure was far higher than that measured. Genotoxic monitoring was performed by nuclease P1-enhanced 32P-postlabelling of DNA adducts in peripheral blood monocytes, and DNA single strand breaks, sister chromatid exchange, and micronuclei in lymphocytes. The content of kinetochores in the micronuclei was determined by immunofluorescence with specific antibodies from the serum of CREST patients. RESULTS--No genotoxic effects related to exposure were detected by DNA adducts or DNA single strand breaks and sister chromatid exchange. The only effect related to exposure was an increase in kinetochore positive micronuclei in peripheral lymphocytes; the frequency of total micronuclei in peripheral lymphocytes did not change. Smoking was confirmed by measurement of plasma cotinine, and no confounding effect was found on any of the cytogenetic variables. CONCLUSIONS--Low occupational exposure to styrene, benzene, and ethylbenzene did not induce alterations of genotoxicological variables except kinetochore positive micronuclei. This is the first reported use of the CREST technique for an in vivo study in occupational toxicology, which thus could serve as a valuable and sensitive technique for toxicogenic monitoring.     

Health effects of long-term mercury exposure among chloralkali plant workers

BACKGROUND: Inorganic mercury is toxic to the nervous system, kidneys, and reproductive system. We studied the health effects of mercury exposure among former employees of a chloralkali plant that operated from 1955 to 1994 in Georgia. METHODS: Former plant workers and unexposed workers from nearby employers were studied. Exposure was assessed with a job-exposure matrix based on historical measurements and personnel records. Health outcomes were assessed with interviews, physical examinations, neurological and neurobehavioral testing, renal function testing, and urinary porphyrin measurements. Exposure-disease associations were assessed with multivariate modeling. RESULTS: Exposed workers reported more symptoms, and tended toward more physical examination abnormalities, than unexposed workers. Exposed workers performed worse than unexposed subjects on some quantitative tests of vibration sense, motor speed and coordination, and tremor, and on one test of cognitive function. Few findings remained significant when exposure was modeled as a continuous variable. Neither renal function nor porphyrin excretion was associated with mercury exposure. CONCLUSIONS: Mercury-exposed chloralkali plant workers reported more symptoms than unexposed controls, but no strong associations were demonstrated with neurological or renal function or with porphyrin excretion.     

Incidence of Raynaud's phenomenon in relation to hand-arm vibration exposure among male workers at an engineering plant a cohort study

Background  

The objective of this study was to assess the incidence of Raynaud's phenomenon in relation to hand-arm vibration exposure in a cohort consisting of male office and manual workers.     

Endocrine profiles of male workers with exposure to trichloroethylene

The objective of this study was to examine the endocrine profiles of a group of male workers chronically exposed to trichloroethylene (TCE) in an electronics factory. A total of 124 workers participated in a preliminary study, for which 85 satisfied the selection criteria and were recruited to take part in a more detailed study. Each of the 85 workers had urine collected and analyzed for trichloroacetic acids (TCA) on the day blood was taken for analysis of serum testosterone (T), follicle-stimulating hormone (FSH), dehydroepiandrosterone sulphate (DHEAS), and sex-hormone binding globulin (SHBG). Environmental TCE exposures were conducted for 12 workers. The geometric mean concentration of environmental TCE was 29.6 ppm (range 9–131) and the mean urine TCA was 22.4 mg/g creatinine (range 0.8–136.4). The results showed that years of exposure to TCE were significantly correlated with DHEAS and negatively correlated with SHBG and T levels. Serum FSH, T, and SHBG levels showed a gradual decline with increasing years of exposure to TCE. This dose-response decrease indicated that there was a disruption of peripheral endocrine function. This disruption could be a result of TCE-induced liver malfunction. The most dramatic change was that the increase in DHEAS concentration was associated with years of exposure to TCE, rising from 255 to 717.8 ng/ml for <3 to ≥7 years exposure, respectively. This evidence suggests that chronic exposure to TCE may also affect adrenal function. These findings, however, must be confirmed by further investigations. Am. J. Ind. Med. 32:217-222, 1997. © 1997 Wiley-Liss, Inc.     

Measurement of the exposure of workers to pesticides

There is not a single pesticide for which the interrelationships between occupational exposure by different routes, the fate of the compound in the human body, and its clinical effects are all adequately known.     

Assessment of exposure to chloramphenicol and azathioprine among workers in a South African pharmaceutical plant

There have been very few published studies that have evaluated exposure to myelotoxic drugs among production workers in pharmaceutical plants. Previous studies have focussed mainly on nurses and evaluated exposure to cytotoxic drugs using urine mutagenicity as a marker of exposure. The aim of this study was to evaluate the exposure of workers involved in the production of chloramphenicol and azathioprine. Exposure was evaluated utilising biological monitoring, biological effect monitoring and environmental monitoring. Biological monitoring included plasma chloramphenicol levels, plasma 6-mercaptopurine and urine 6-thiouric acid levels. These were analysed using high performance liquid chromatography. Myelotoxic effect was assessed by measuring the haematological indices of bone. marrow function. The exposed 17 workers were compared to matched controls of equal numbers. Neither substance could be detected in serum nor urine by the analytical methods employed. However, haematological indices demonstrated a significantly decreased mean reticulocyte and neutrophil count in the azathioprine exposed group. Industrial hygiene measurements demonstrated contamination of the air inside the airhood of exposed workers. In conclusion, it is evident that workers involved in the production of both these drugs are at risk of developing adverse health effects. Furthermore, more sensitive analytical methods need to be developed to evaluate absorption of myelotoxic chemicals among occupationally exposed workers.     

某炼钢厂150名职业性噪声接触女工健康状况调查

目的探讨职业性噪声接触女工的健康状况,为保护女工的健康提供理论依据。方法选择150名某炼钢厂接触噪声女工作为接触组,另选择行政后勤女工125名作为对照组,将其结果比较分析。结果接触组的听力损伤、神经衰弱、月经失调、高血压检出率分别为23.33%、21.33%、19.33%、10.67%;均高于对照组的3.20%、12.00%、9.60%、6.40%,前3项两组比较,差异有统计学意义(P<0.05或P<0.01)。疾病检出率随着作业工龄的增加而增加。结论接触噪声女工的身体健康状况较对照组差,应予以重视。     

Tremor in workers with low exposure to metallic mercury

In a fluorescent lamp production factory, a newly developed lightweight balance-tremormeter was used to measure postural tremor of the finger in 21 workers (ages 28 to 61) exposed for 0.5-19 yr to metallic mercury. In addition, tremor was measured in an indirect way by means of a "hole-tremormeter." The excretion of mercury in urine was 9-53 (average 20) mumol/mol creatinine. With increasing mercury excretion, the following parameters increased: the acceleration of the tremor, the contribution of the neuromuscular component (8-12 Hz) to the power spectrum of the acceleration, the width of the power-spectrum and the score on the hole-tremormeter. The study indicates that exposure to metallic mercury below the current TLV (50 micrograms/m3) may increase the tremor of the finger.     

Morbidity with temporary disability among workers in the main professions at the machine-building plant

The article contains the results of a profound analysis of morbidity with temporary disability among the workers of a machine-building plant's main shops. According to Dr E. L. Notkin's classification, the temporary disability indices were 'extremely high', whereas in the group of 'noise-affected' workers, the major morbidity was presented by acute respiratory and cardiovascular cases. A correlation was established between auditory pathology++ and hypertension disease, and on the other hand, between the chronic respiratory pathology level and the number of acute respiratory cases. A relation was traced between neurosensory++ hypoacusis and cardiovascular diseases.     

Morbidity prevalence study of workers with potential exposure to epichlorohydrin

This study examined the morbidity experience from 1981 to 1988 of two cohorts (Shell cohort and Enterline cohort) of workers who had potential exposure to epichlorohydrin (ECH). The morbidity prevalence data for this study were extracted from the morbidity section of the Shell health surveillance system which included all illness and absence records in excess of five days. For both cohorts, the standardised morbidity ratios (SMRs) for all causes and all neoplasms were similar to an internal comparison group. There were no increases in heart disease morbidity for the Shell cohort (SMR = 97) or the Enterline cohort (SMR = 90). The SMRs for heart disease in the lower exposure group of the Shell cohort were 101 and 93 for the corresponding Enterline cohort. They were 92 and 87, respectively, in the higher exposure group. The increased risk of heart disease mortality reported by Enterline et al in workers more heavily exposed to ECH was not confirmed in this morbidity study. Morbidity from skin and subcutaneous tissue disorders, however, was found to be increased significantly in the Shell cohort. The SMR was 98 for the lower exposure group and 195 for the higher exposure group. A review of the original morbidity reports for each case suggested that factors unrelated to exposure to ECH such as the physical demands of a particular job, amount of time outside--for example, exposure to poison ivy--and other underlying medical conditions may be of greater importance than exposure to ECH.