Blue-yellow deficiency in workers exposed to low concentrations of organic solvents

Objectives: To evaluate the effects of low concentrations of organic solvents on color vision. Methods: Color vision was examined in 24 workers exposed to mixtures of solvents and in 24 control subjects. Exposure to mixtures was below the threshold-limit values. Color vision ability was assessed using the Ishihara plates (to screen for congenital dyschromatopsia), the Farnsworth panel D-15 test, the Lanthony desaturated panel D-15 test, and the Standard Pseudoisochromatic Plates part 2 (SPP2 test). Results: The comparatively less sensitive Farnsworth panel D-15 test failed to show any difference between the groups, but the Lanthony panel D-15 desaturated test as well as the SPP2 test showed a significant impairment in the exposed group. Errors were of the blue-yellow type. Conclusion: This study gives further evidence that even mixtures of organic solvents at concentrations below the threshold-limit values may impair color vision. Received: 7 January 1997 / Accepted: 14 May 1997     

Influence of solvents,alcohol, smoking and age on biological tests

Summary The association between a number of blood and serum quantities and industrial organic solvent exposure and poisoning, alcohol consumption, smoking, and age was analysed in 277 subjects by multiple regression analysis. Solvent poisoning was associated with changes in S-creative kinase concentrate at the P < 0.001 level (higher if exposed, lower if non-exposed at the examination time). Solvent exposure seemed to potentiate the effects of smoking on B-hemoglobin cone. and B-erythrocyte volume fraction, and the effect of age on S-creatinine cone. at the P < 0.05 level, while there was no interaction between alcohol consumption and solvents. Alcohol consumption in itself, as well as smoking and age, were highly significantly associated with changes in a large number of blood and serum quantities. There was no difference in the alcohol markers (mean erythrocyte volume = MCV, S-alanine aminotransferase and S-urate) in patients with solvent poisoning compared to healthy volunteers. The results indicate that studies on the effects of solvents on haematology and biochemistry are not valid unless the effects of alcohol, smoking and age are established; and that excessive alcohol consumption is an unlikely explanation for the symptoms of patients with solvent poisoning. The findings suggest that smoking and age may have combined effects with solvents.     

Multiple exposure to solvents in the workplace

Conclusions In conclusion, it must be stressed that scientific studies need to be undertaken in the near future to solve the various problems mentioned above. These studies should also take account of all the non-occupational factors that, may alter the toxicokinetics and the toxicodynamics of solvents. At present, however, existing data obtained both from experimental research in animals and in volunteers and from studies carried out in workers liable to occupational exposure can be used in preparing lists similar to those we have proposed in Table 1, in which metabolic interferences are reported for the various substances. Although incomplete and only indicative, these lists may be a useful guide to the correct preventive measures to be implemented in various workplace situations. They should, at the very least, stimulate readers to extend their knowledge of the toxicology of combined exposure to solvents.     

Effects of combined exposure to trichloroethylene and alcohol on mental capacity

Summary Adult male volunteers inhaled a constant concentration of 200 ppm trichloroethylene for 2 1/2 hours, ingested ethanol (0.35 gr/kg body weight) or were exposed to the combination of trichloroethylene and ethanol. After exposure Ss performed a few mental tasks. Performance as indicator of external load and the physiological parameters heart rate, sinus arrhythmia and in the final experiment also breathing rate as indicators of functional load were used as dependent variables. Exposure to a combination of trichloroethylene and alcohol leads to an increase of functional load while performing a mental task, even when exposure to only trichloroethylene or alcohol has no effect. Difficulties in experimental design and interpretation of research of combined stress are discussed.     

Neurobehavioral effects of exposure to trichloroethylene through a municipal water supply

We studied a population-based sample of 143 residents of a community in which the municipal water supply had been contaminated with trichloroethylene (TCE) and related chemicals from several adjacent hazardous waste sites between 1981 and 1986. A hydraulic simulation model was used in conjunction with a geographic information system (GIS) to estimate residential water supply exposures to TCE; 80% of the participants had potential TCE exposure exceeding the maximum contaminant level (5 ppb). The Neurobehavioral Core Test Battery (NCTB), tests of visual contrast sensitivity, and the profile of mood states (POMS) were administered approximately 6 years following peak concentrations of TCE in municipal drinking water. Multivariate analysis of variance adjusted for potential confounders was used to compare mean test scores of residents classified by estimated TCE exposure (< or =5, >5-10, >10-15, >15 ppb). TCE exposure >15 ppb was associated with poorer performance on the digit symbol, contrast sensitivity C test, and contrast sensitivity D test and higher mean scores for confusion, depression, and tension. We found evidence of a strong interaction between exposure to TCE and alcohol consumption; the associations for the NCTB and POMS among persons in the high-exposure group who also consumed alcohol were stronger and were statistically significant for the Benton, digit symbol, digit span, and simple reaction time tests, as well as for confusion, depression, and tension. This study adds to the evidence that long-term exposure to low concentrations of TCE is associated with neurobehavioral deficits and demonstrates the usefulness of GIS-based modeling in exposure assessment.     

Altered responsiveness to alcohol after exposure to organic lead

Ethyl alcohol is known to effect the functional integrity of the limbic system, particularly the hippocampus, and to alter behaviors which are thought to be mediated through limbic function. Organometals also compromise the limbic system and result in deficits in learning and memory. Since both alcohol and organoleads are present in the environment and seem to influence limbic integration, the interaction of these two compounds was assessed in the present experiment. Thirty male rats of the Fischer-344 strain were divided into three equal groups and were given injections of trimethyl lead (TML) (8.0 or 17.0 mg/kg/ml SC) or the saline vehicle. Fourteen days later, all animals were challenged with a single hypnotic dose of ethanol (3.5 g/kg IP). The 20% v/v solution of alcohol was prepared in water from a stock solution of 95% ethanol. The latency to loss of the righting reflex and duration of sleep time were recorded while the rats were kept in sound-attenuating chambers. The rats treated with the highest dose of TML manifested significantly longer latencies to lose the righting reflex and shorter durations of sleep than did controls. These results suggest that exposure to environmental lead may alter the biological and behavioral responsiveness of an animal to alcohol.     

Occupational exposure to solvents and cerebellar,brainstem and vestibular functions

Summary Forty-eight persons (age 44, SD 9 years) exposed to paint solvents and 40 nonexposed referents (age 45, SD 9 years) were examined. The duration of exposure was 4 to 30 (mean 20) years and the life-time exposure level was estimated to have been 10 to 330 (mean 60%) of the hygienic standard. The methods used were a neurological examination, electroencephalography, brainstem auditory-evoked potentials, electronystagmography, and posturography. Lifetime exposure was estimated on the basis of a detailed occupational history and environmental measurements made at the work places over several years. The average weekly alcohol consumption was established in a detailed interview. Due to the small number of subjects examined, the study was inconclusive. The findings classified as abnormal were slightly more common in the exposed than in the referents, and in the persons who used alcohol than in the non-users. The differences were not statistically significant, and no exposure-response relationships were found.     

Increased acquired dyschromatopsia among solvent-exposed workers: an epidemiology study on 249 employees of an aluminum-foil printing factory

Objective: To analyze the effects on color vision of chronic exposure to mixtures of solvents including ethyl acetate, ethanol, and ketones among the workers of a large factory specializing in the manufacture of photoengraved aluminum packaging. Methods: We analyzed a group of 129 subjects who had been exposed to solvents for more than 3 years (mean age 40 years, range 25–59 years) and a nonexposed group of 120 subjects (mean age 41 years, range 21–57 years). The two groups had a similar length of service (17 and 19 years on average, respectively). The exposed subjects consumed more tobacco and alcohol than the nonexposed workers. The study involved administration of the Lanthony D-15 desaturated test. The subjects were classified as having or not having dyschromatopsia on the basis of Lanthony's criteria and the chromatic confusion index (CCI) was calculated according to Bowman's method. After observation of the work stations and analysis of an occupational questionnaire the findings were used to construct a cumulative exposure index covering the whole of each subject's working life. Air samples were taken at each work station and in each production sector to determine current exposure. Results: The average cumulative exposure index was 194 (median 174, range 27–513). The average hygienic effect index (according to ACGIH recommendations), regularly used for atmospheres containing mixtures of products, varied between 12% and 27% of the occupational limit values permitted under French legislation. As regards color vision, 23% of the exposed group had dyschromatopsia, as did 13% of the nonexposed group, with the odds ratio (OR) adjusted for age and consumption of tobacco and alcohol being 1.99 (1.02, 3.89). The analysis of the dose-response relationship according to the cumulative exposure index showed an OR of 1.59 for the lowly exposed group (index ≤174) and an OR of 2.40 for the highly exposed group (index >174) as compared with the nonexposed group. Subjects with complex color vision loss (n=23) had a significantly higher cumulative exposure index than those with blue-yellow loss (n=23; 232 versus 155; P=0.04). The CCI was on average higher in the exposed group, but the difference between the two groups was not significant. Conclusion: The results of this study are in favor of an increased risk for impairment of chromatic discrimination among workers exposed to mixtures of solvents including mainly ethyl acetate, ethanol, and ketones. Received: 10 September 1996 / Accepted: 12 December 1997     

2008年-2010年杭州市工业企业有机溶剂职业卫生调查与分析

目的:全面了解杭州市工业企业2008年-2010年作业场所空气中有机溶剂污染情况,预防有机溶剂职业中毒发生。方法:采用现场劳动卫生学调查和作业场所空气中有害物质监测结果进行分析。结果:作业场所空气中苯、甲苯、二甲苯、正己烷、甲醇、丙酮和环氧乙烷存在超标情况,苯最高短时间接触浓度超过国家标准8.8倍。结论:工业企业使用有机溶剂作业场所存在职业中毒隐患,必须采取综合职业病防治措施,预防职业中毒的发生,保护工人健康。     

饮酒与职业噪声暴露对听力损失的联合作用

目的 探讨饮酒与听力损失的关系以及饮酒和职业性噪声对听力损失的联合作用.方法 利用回顾性队列研究,选择广州市某大型空调生产企业连续性噪声作业人员2.44名男性饮酒者为饮酒组,在相同的噪声暴露环境中选择140名男性不饮酒者为对照组,两组间除饮酒外,其他均均衡可比.按照<作业场所噪声测量规范>(WS/T 69-1996)要求对噪声暴露作业场所进行测点选择和噪声强度测量[dB(A)],并计算累积噪声暴露量(CNE).按GB7583-87要求,对工人进行左、右耳500～6000Hz内6个频率的纯音气导听阈测试,并问卷调查其一般情况、个人生活史、职业史、噪声暴露史、家族性耳聋史以及耳毒性药物使用史等.利用t检验、有序多分类logistic回归分析、卡方检验分析噪声和饮酒对听力的影响以及两者的联合作用.结果 同一噪声暴露环境下,在4 000 Hz频段,饮酒组左、右耳听阈位移分别为(29.9±12.9)dB和(30.0±13.5)dB;6000Hz听闻位移为(26.9±11.8)dB和(27.3±15.3)dB,均高于对照组(P<0.05).饮酒组听力损失的发生率为21.7%,对照组为10.7%,两组比较差异有统计学意义(P<0.01),年饮酒量达32L及以上听力损失发生的相对危险度是不饮酒的2.632倍(P<0.05).累积噪声量达80 dB(A)及以上时,饮酒和职业噪声听力损失的RR值分别为3.353和4.643,饮酒与职业噪声联合作用的RR值(9.662)大于两个变量独立作用之和.结论 大量饮酒可导致听力损失发生率增高,在高强度噪声暴露情况下,饮酒和职业噪声暴露对听力损失存在协同作用.     

Effect of combined occupational exposure to noise and organic solvents on hearing

Noise exposure has been commonly regarded as the main hazard of occupational hearing loss. Recent studies indicate that several chemicals, including organic solvents have ototoxic effects. This study aimed at evaluating the hearing of workers exposed to both noise and a mixture of organic solvents at concentrations anticipated as safe. The study comprised three groups. The first one included 70 workers exposed to noise only, the second group consisted of 93 workers exposed to organic solvents and noise, and the control group included 59 individuals exposed to neither noise nor organic solvents. The three groups were matched for age, socioeconomic status, and smoking habit. The results of this study revealed that there was no statistically significant difference between the two exposed groups as regards the duration of exposure. There was a highly statistically significant difference between the two exposed groups as regards the different types of hearing loss (conductive deafness, sensory neural hearing loss, and mixed type) compared with the control one. Our study reported that sensory neural hearing loss occurred earlier in subjects with combined exposure to noise and solvents at a mean duration of exposure (16.38?±?9.44 years) compared to (24.53?±?9.59 years) the subjects with sole exposure to noise. The difference between the two groups was statistically significant regarding this type of hearing impairment (p < 0.05). There was a positive significant correlation between hearing impairment and duration of exposure in the two exposed groups. As regards the results of the environmental monitoring, both noise exposure levels (dB) and levels of different organic solvents measured (mg/m(3)) in different work departments were less than the levels recommended by Egyptian Environmental Law No. 4 for 1994. It is recommended that in the case of combined exposure, noise and solvent levels should be lowered than the permissible limits recommended for either alone.     

Acute symptoms during non-inhalation exposure to combinations of toluene, trichloroethylene, and n-hexane

Objectives: To study the acute effect of exposure to a mixture of three commonly used solvents in humans using a route of exposure not involving the nose and lungs, in this case a gastrointestinal application. Methods: In a 2³-factorial experiment eight healthy male volunteers were exposed to the eight combinations of toluene (1.5 and 4 mg · min⁻¹) trichloroethylene (1.5 and 4 mg · min⁻¹), and n-hexane (0.3 and 1.0 mg · min⁻¹) for 60 min given into the stomach via a feeding tube. The body burden was measured by the exhaled solvent concentrations and the urinary excretion of metabolites during and after exposure. The subjective ratings of tiredness, sleepiness, headache, nausea, feeling of intoxication, and dizziness were estimated by continuous linear analogue rating scales before and 30, 90, and 240 min after the start of exposure. Results: Concentrations of the three solvents in the end exhaled air varied between 0 and 46 mg · min⁻³. The ratings of symptoms were generally low and there was no difference between the high and low doses. Neither was there any correlation between the concentration of solvents in the exhaled air and the ratings. Conclusions: The study show no effects at levels in end exhaled air of mixtures of solvents which in inhalation studies have given signs of a possible neurotoxic effect. The lack of symptoms using this alternative route supports the hypothesis that “neurotoxic” symptoms in relation to exposure to very low air concentrations of solvents are mainly indirect, mediated by irritation or smell. Received: 11 January 1999 / Accepted: 3 May 1999     

1989至2003年全国有机溶剂重大急性职业中毒的特征

目的探讨有机溶剂重大急性职业中毒事故的发生规律和特点,为制定有机溶剂中毒的防制策略提供科学依据。方法对1989至2003年15年间收集到的有机溶剂重大急性职业中毒资料进行描述性分析。结果(1)15年间共报告有机溶剂重大急性职业中毒事故58起,中毒393例,中毒死亡48人,总中毒率为51．2%,总中毒死亡率为12．2%；平均中毒年龄(30．9±8．8)岁,平均中毒死亡年龄(30．6±12．0)岁。(2)直接导致中毒的有机溶剂有11种,以苯及其同系物为主。(3)有机溶剂重大急性职业中毒以制造业、化学工业、建筑、运输与仓储、服务业与商业等行业多发,喷漆和清洗岗位的危险性较高,事故相对集中发生在4～7月份。(4)导致中毒事故发生的主要原因是没有密闭通风排毒设备或效果不好、没有个人防护设备、缺乏安全教育和没有安全操作规程等。结论作业场所要加强通风,避免劳动者皮肤直接接触有机溶剂,使用无毒或低毒的替代物质。     

Acquired intolerance to organic solvents and results of vestibular testing

Among 160 consecutive patients referred to the Clinic of Occupational Medicine, Rigshospitalet, for symptoms connected with exposure to organic solvents, 20 exhibited symptoms of acquired intolerance to minor amounts of organic solvents. Later, an additional 30 consecutive patients with symptoms of acquired intolerance were included, yielding a total of 43 men and 7 women. The characteristics of the clinical syndrome described are complaints of dizziness, nausea, and weakness after exposure to minimal solvent vapor concentrations. After having tolerated long-term occupational exposure to moderate or high air concentrations of various organic solvents, the patients became intolerant within a short period of time. Since dizziness was a frequent complaint, we tried to obtain a measure of the patients' complaints using vestibular tests. As a diagnostic test the combined vestibular tests had a sensitivity of 0.55 and a specificity of 0.87. No differences between patients with and without intolerance could be detected by the vestibular tests used. We conclude that acquired intolerance to organic solvents is a new but characteristic and easily recognizable syndrome, often with severe consequences for the patient's working ability.     

Primary liver cancer and exposure to solvents

Summary A case-referent study was done on the possible association between primary liver cancer (ICD 155.0) and occupational exposures. In all, 374 cases were reported to the Finnish Cancer Registry in 1979 and 1980. After the exclusion of wrong diagnoses, nonrespondents and cases for whom the primary site was uncertain, 126 cases (64 men and 62 women) remained. Each case was matched for sex, age (± 5 years), vital status and geographical district with two cases of coronary infarction selected from hospital records without any knowledge of occupational history. Nonrespondence (38%) reduced the number to 175 referents (82 men and 92 women). A questionnaire on former employment and tasks was mailed to living subjects (6+6) and to the next of kin of deceased patients. An industrial hygienist then evaluated the exposure history blindly and, whenever necessary, contacted the workplace or the next of kin for more details. Only exposures commencing 10 years or more before diagnosis were considered. Altogether six female cases but no referent had been exposed to solvents. One had been exposed to chlorinated solvents in dry cleaning and two others had used both carbon tetrachloride and aromatic and aliphatic solvents. Three cases had been exposed to mixtures of aliphatic and aromatic solvents, but not chlorinated hydrocarbons. By contrast, the men did not differ with regard to exposure to solvents. Two cases and five referents were classified as having been exposed to solvent mixtures. The present results are hypothesis generating only, and the excess solvent exposure found for women must be confirmed in other studies before any conclusions can be drawn.Part of the results have been presented at the third Conference on Epidemiology in Occupational Health, 28–30 September, 1983 in Singapore     

Occupational exposure to solvents and male infertility

OBJECTIVES—To determine whether, in a case-referent study of infertility patients, cases with low motile sperm count were more likely than referents to have had exposure to organic solvents.
METHODS—Occupations of men attending fertility clinics in Canada were assigned codes reflecting probable exposure to organic solvents, at four grades of intensity, using a job exposure matrix previously developed. A case referent design was used, with cases being defined as men with <12×10⁶/ml motile sperm. Information from 656 men in manual work attending a single clinic in Montreal in 1972-91 was used for the main study. A separate analysis was conducted with information for 574 men in manual work attending 10 further clinics across Canada in 1984-7.
RESULTS—In the Montreal series a significant association was found between intensity of exposure to solvents and clinical findings of <12×10⁶/ml motile sperm. Odds ratios (ORs), after allowing for confounding, were 2.07 (95% confidence interval (95% CI) 1.24 to 3.44) for moderate exposure to solvents and 3.83 (95% CI 1.37 to 10.65) for high exposure. In the second series of 568 men, the effect was confirmed at high exposure to solvents (OR 2.90, 95% CI 1.01 to 8.34) but not at moderate exposure (OR 1.01, 95% CI 0.53 to 1.92).
CONCLUSIONS—Exposure to organic solvents is common both at work and in recreational pursuits. The results of this study suggest that efforts should be made to identify the compounds hazardous to male fertility, and if the risk is confirmed, to regulate their use.


Keywords: infertility; solvents; male manual workers     

Effects of alcohol on autonomic responses and thermal sensation during cold exposure in humans

We investigated the effects of alcohol on thermoregulatory responses and thermal sensations during cold exposure in humans. Eight healthy men (mean age 22.3 ± 0.7 year) participated in this study. Experiments were conducted twice for each subject at a room temperature of 18°C. After a 30-min resting period, the subject drank either 15% alcohol at a dose of 0.36 g/kg body weight (alcohol session) or an equal volume of distilled water (control session), and remained in a sitting position for another 60 min. Mean skin temperature continued to decrease and was similar in control and alcohol sessions. Metabolic rate was lower in the alcohol session, but the difference did not affect core temperature, which decreased in a similar manner in both alcohol and control sessions (from 36.9 ± 0.1°C to 36.6 ± 0.1°C). Whole body sensations of cold and thermal discomfort became successively stronger in the control session, whereas these sensations were both greatly diminished after drinking alcohol. In a previous study we performed in the heat, using a similar protocol, alcohol produced a definite, coordinated effect on all autonomic and sentient heat loss effectors. In the current study in the cold, as compared to responses in the heat, alcohol intake was followed by lesser alterations in autonomic effector responses, but increased changes in sensations of temperature and thermal discomfort. Overall, our results indicate that although alcohol influences thermoregulation in the cold as well as in the heat, detailed aspects of the influence are quite different.     

Dementia and occupational exposure to organic solvents

OBJECTIVES: To investigate whether occupational exposure to organic solvents increases the risk of dementia. METHODS: Cases of dementia were identified from the computed tomography records of eight neuroradiology centres in England and Wales, and were compared with two sets of controls investigated at the same centres. The first set of controls were patients with brain cancer and the second set were patients with other disorders that were not chronically disabling. Lifetime occupational histories were obtained through a postal questionnaire completed by the subjects or their next of kin. Associations between dementia and occupation were examined by logistic regression. RESULTS: Usable questionnaires were returned for 204 (61%) of the cases, 225 (51%) of the controls with brain cancer, and 441 (61%) of the other controls. The findings with each of the two sets of controls were similar. In comparison with all controls combined, cases had less often worked ever as a painter or printer (odds ratio (OR) 0.6, 95% confidence interval (95% CI) 0.3 to 1.2), and were less likely to have worked for > 1 year as a printer, painter, or launderer or dry cleaner (OR 0.6, 95% CI 0.3 to 1.4). CONCLUSIONS: These findings provide no support for the hypothesis that occupational exposure to solvents is a cause of dementia. An excess risk in subsets of workers with extremes of exposure cannot be discounted, but the data indicate that any influence of exposure to solvents on the overall incidence of severe dementia in the general population of England and Wales is small.