Chronic bronchitis, work related respiratory symptoms, and pulmonary function in welders in New Zealand

OBJECTIVES: A cross sectional study of respiratory symptoms and lung function in welders was performed at eight New Zealand welding sites: 62 current welders and 75 non-welders participated. METHODS: A questionnaire was administered to record demographic data, smoking habit, and current respiratory symptoms. Current and previous welding exposures were recorded to calculate a total lifetime welding fume exposure index. Forced expiratory volume in one second (FEV1), forced vital capacity (FVC), and peak expiratory flow (PEF) were measured before the start of the shift. RESULTS: There were no significant differences in ethnicity, smoking habits, or years of work experience between welders and non-welders. Symptoms of chronic bronchitis were more common in current welders (11.3%) than in non-welders (5.0%). Of those workers with a cumulative exposure index to welding fume > or = 10 years, 16.7% reported symptoms of chronic bronchitis compared with 4.7% of those with a cumulative exposure index < 4 years (odds ratio (OR) 4.1, 95% confidence interval (95% CI) 0.90 to 17.6). Workers with chronic bronchitis had significantly lower measures of baseline PEF (p = 0.008) and FEV/FVC ratio (p = 0.001) than workers without chronic bronchitis. Multivariate analysis showed that current smoking (OR 9.3, 1.0 to 86.9) and total exposure index to welding fumes > 10 years (OR 9.5, 1.3 to 71.9) were independent risk factors for chronic bronchitis. The report of any work related respiratory symptom was more prevalent in welders (30.7%) than non-welders (15.0%) and workers with these symptoms had significantly lower FEV, (p = 0.004) and FVC (p = 0.04) values. Multivariate analysis identified a high proportion of time spent welding in confined spaces as the main risk factor for reporting these symptoms (OR 2.8, 1.0 to 8.3). CONCLUSION: This study has documented a high prevalence of symptoms of chronic bronchitis and other work related respiratory symptoms in current welders. Also, workers with chronic bronchitis had reduced PEF and FEV/FVC compared with those without chronic bronchitis. These symptoms related both to cigarette smoking and a measure of lifetime exposure to welding fume.

 

     

Lung function of welders of zinc-coated mild steel: cross-sectional analysis and changes over five consecutive work shifts

Spirometric lung-function measurements were conducted 5 days before and after the work shift of 11 welders of zinc-coated steel, ten nonwelders who were indirectly exposed to welding fumes, and 17 controls. The exposure to dust and zinc of all participants was monitored personally using PAS-6 samplers. Geometric mean concentrations for welders were 0.91 mg/m3 (dust) and 34.0 micrograms/m3 (zinc). Cross-sectional analysis of Monday morning values showed no differences in lung-function parameters between groups. However, the number of years the participants were engaged in welding was of borderline statistical significance and correlated negatively with values of FEV1 and FEV1/FVC. Changes in lung function over a work shift or a working week were not related to the exposure level.     

Chronic effects of welding exposure on pulmonary function tests and respiratory symptoms.

OBJECTIVES--The respiratory effects of exposure to welding fumes have been investigated in numerous studies; but results of these studies have not been consistent. The aim of the present study was to investigate the respiratory effects of welding exposure in a large group of manual are welders exposed primarily to mild steel welding processes in confined spaces without respiratory protection. METHODS--Respiratory symptoms and spirometry were studied in 110 welders and 55 controls. The welders and controls were of similar average age and height; smoking habits of the groups were similar. Chest x ray films were taken to exclude people with radiological abnormalities that may influence pulmonary function tests. Welders were grouped according to smoking habits and duration of employment (< 20 years or > 20 years). RESULTS--No gross radiological abnormalities were found. Respiratory symptoms and chronic bronchitis were more prevalent in welders (P < 0.05). Welders who were smokers showed a higher frequency of chronic bronchitis than controls who smoked (P < 0.05). No significant difference in the occurrence of chronic bronchitis was found between welders who smoked and welders who were non-smokers or exsmokers. Compared with the controls, forced vital capacity (FVC), forced expiratory volume in one second (FEV1), peak expiratory flow (PEF), and maximum midexpiratory flow (MMEF) were significantly lower in welders (mean values of FVC for welders and controls were 86.06 (25.74) and 96.40 (13.03); and values for FEV1 were 87.54 (13.70) and 95.36 (12.40) respectively; P < 0.01). There was no significant difference in pulmonary function tests between welders who were non-smokers and controls who were non-smokers; whereas FVC, FEV1, PEF, and MMEF were significantly lower in welders who smoked than controls who smoked (P < 0.01). There were no significant differences in pulmonary function tests and occurrence of chronic bronchitis between welders with more or less than 20 years at work. CONCLUSION--Welders working in conditions of inadequate ventilation, have increased risk of chronic bronchitis and impairment of pulmonary function.     

Lung function in Pakistani welding workers

Our objective was to study the effects of welding fumes and their duration of exposure on lung function. This was a matched case-control cross-sectional study of spirometry in 50 nonsmoking manual metal arc welders who work without the benefit of welding fume control ventilation or respiratory protective devices. Welding workers, with exposures longer than 9 years, showed a significant reduction in spirometry (forced expiratory volume in one second [FEV1], FEV1/forced vital capacity [FVC%], and peak expiratory flow [PEF]) relative to controls. Lung function in nonsmoking welding workers is impaired and stratification of results shows a dose-effect of years of welding on lung function. This effect primarily shows an obstructive pattern of airways disease. Preventive measures in developing countries have to be adopted to avert long-term lung damage in welders.     

Relation between various chromium compounds and some other elements in fumes from manual metal arc stainless steel welding.

For the years 1987-1990 160 individual samples of manual metal arc stainless steel (MMA/SS) welding fumes from the breathing zone of welders in four industrial plants were collected. Concentrations of soluble and insoluble chromium (Cr) III and Cr VI compounds as well as of some other welding fume elements (Fe, Mn, Ni, F) were determined. Concentration of welding fumes in the breathing zone ranged from 0.2 to 23.4 mg/m3. Total Cr amounted to 0.005-0.991 mg/m3 (including 0.005-0.842 mg/m3 Cr VI). Total Cr content of fumes varied from 0.1 to 7.4%. The distribution of particular Cr compounds was: 52.6% soluble Cr (including 50.7% Cr VI), 65.5% total Cr VI, and 11.4% insoluble Cr VI. The results obtained indicate that MMA/SS welding is a process that could be highly hazardous to human health. Evaluation of occupational exposure has shown that MMA/SS welders may exceed the admissible concentrations of soluble and insoluble Cr VI forms as well as of Mn and Ni. In the plants investigated the sum of the ratios of concentrations of particular welding fumes in the breathing zone of welders exceeded corresponding maximum allowable concentration values by 24 times (including 17 times for total Cr VI). Due to the variety and changeability of particular parameters occurring in the working environment, the composition of MMA/SS welding fumes (in the welder's breathing zone) is so variable that it is not possible to assess the exposure by means of one universal exposure indicator (maximum additive hygienic limit value). The evaluation should be based on the results of measurements of concentrations of particular elements in welding fumes.     

Change in obstructive pulmonary function as a result of cumulative exposure to welding fumes as determined by magnetopneumography in Japanese arc welders

OBJECTIVES: To examine the effect of chronic exposure to welding fumes on pulmonary function by a direct estimate of fumes accumulated in the lungs. METHODS: The strength of the residual magnetic field of externally magnetised lungs (LMF) was used as an estimate of fumes accumulated in the lungs. The results of forced spirometry manoeuvres obtained in 143 of 153 male welders in the original sample were cross sectionally evaluated according to LMF. Seven conventional forced spirogram indices and two time domain spirogram indices were used as pulmonary function indices, and height squared proportional correction was performed when necessary. RESULTS: The distribution of LMF values was considerably skewed towards positive. There was a weak but significant positive relation between age and log transformed LMF. Obstructive pulmonary function indices correlated well with LMF. After adjustment for age and smoking, however, a significant association with LMF was only found with percentage rate of forced expiratory volume in one second (FEV1%) divided by forced vital capacity (FVC) and mu, and average component of assumed time constant distribution of lung peripheral units. Neither FVC nor vital capacity (VC), as indices of restrictive disorders, showed a significant association with LMF. Based on the results of multiple regression analyses, a 0.6% decrease in FEV1% and 0.039 unit increase in mu were expected for each doubling of LMF. CONCLUSION: Obstructive changes in pulmonary function were found to be related to level of cumulative exposure to welding fume in male Japanese arc welders after controlling for age and smoking, assuming that LMF adequately reflects accumulation of welding fumes in the lungs.

 

     

Lung-retained contaminants,urinary chromium and nickel among stainless steel welders

Summary The magnetic method of measuring the amount of lung retained contaminants as well as urinary chromium and nickel determinations have been performed among 83 stainless steel (SS) welders who have used matural metal arc (MMA) and tungsten inert gas (TIG) welding techniques. The welders were divided into four groups according to the time percentage used for MMA welding. Only exposure to MMA/SS welding fumes resulted in clearly elevated chromium concentrations in the urine, the correlation coefficient between the values of urinary chromium and MMA/SS percentage being very significant (P < 0.001). Among the smokers the urinary chromium values were increased (P < 0.05) perhaps owing to contaminated cigarettes. In many workplaces the urinary chromium values of several welders exceeded the value of 30 g/l which is the recommended reference value in Finland. Owing to the solubility properties of nickel compounds in SS welding fumes urinary nickel concentrations were only slightly elevated among MMA/SS welders, and therefore, the urinary nickel determinations do not reflect the level of exposure to nickel compounds. The measured average remanent magnetic field of the chest area correlated well (P < 0.01) with the use of the MMA technique. A very significant correlation (P < 0.001) existed between the average remanent magnetic fields of the chest and the urinary chromium values of MMA/SS welders.     

Semen quality and sex hormones among mild steel and stainless steel welders: a cross sectional study

Welding may be detrimental to the male reproductive system. To test this hypothesis, semen quality was examined in 35 stainless steel welders, 46 mild steel welders, and 54 non-welding metal workers and electricians. These figures represent a participation rate of 37.1% in welders and 36.7% in non-welding subjects. The mean exposure to welding fume particulates was 1.3 mg/m3 (SD 0.8) in stainless steel welders using tungsten inert gas, 3.2 mg/m3 (SD 1.0) in low exposed mild steel welders using manual metal arc or metal active gas (n = 31), and 4.7 mg/m3 (SD 2.1) in high exposed mild steel welders (n = 15). The semen quality of each participant was defined in terms of the mean values of the particular semen parameters in three semen samples delivered at monthly intervals in a period with occupational exposure in a steady state. The sperm concentration was not reduced in either mild steel or stainless steel welders. The sperm count per ejaculate, the proportion of normal sperm forms, the degree of sperm motility, and the linear penetration rate of the sperm were significantly decreased and the sperm concentration of follicle stimulating hormone (FSH) was non-significantly increased in mild steel welders. A dose response relation between exposure to welding fumes and these semen parameters (sperm count excepted) was found. Semen quality decreased and FSH concentrations increased with increasing exposure. Significant deteriorations in some semen parameters were also observed in stainless steel welders. An analysis of information from questionnaires obtained from the whole population including subjects who declined to participate indicated an underestimation of effects due to selection bias. Potential confounding was treated by restriction and statistical analysis. The results support the hypothesis that mild steel welding and to a lesser extent stainless steel welding with tungsten inert gas is associated with reduced semen quality at exposure in the range of the Danish process specific threshold limit values of welding.     

Semen quality and sex hormones among mild steel and stainless steel welders: a cross sectional study.

Welding may be detrimental to the male reproductive system. To test this hypothesis, semen quality was examined in 35 stainless steel welders, 46 mild steel welders, and 54 non-welding metal workers and electricians. These figures represent a participation rate of 37.1% in welders and 36.7% in non-welding subjects. The mean exposure to welding fume particulates was 1.3 mg/m3 (SD 0.8) in stainless steel welders using tungsten inert gas, 3.2 mg/m3 (SD 1.0) in low exposed mild steel welders using manual metal arc or metal active gas (n = 31), and 4.7 mg/m3 (SD 2.1) in high exposed mild steel welders (n = 15). The semen quality of each participant was defined in terms of the mean values of the particular semen parameters in three semen samples delivered at monthly intervals in a period with occupational exposure in a steady state. The sperm concentration was not reduced in either mild steel or stainless steel welders. The sperm count per ejaculate, the proportion of normal sperm forms, the degree of sperm motility, and the linear penetration rate of the sperm were significantly decreased and the sperm concentration of follicle stimulating hormone (FSH) was non-significantly increased in mild steel welders. A dose response relation between exposure to welding fumes and these semen parameters (sperm count excepted) was found. Semen quality decreased and FSH concentrations increased with increasing exposure. Significant deteriorations in some semen parameters were also observed in stainless steel welders. An analysis of information from questionnaires obtained from the whole population including subjects who declined to participate indicated an underestimation of effects due to selection bias. Potential confounding was treated by restriction and statistical analysis. The results support the hypothesis that mild steel welding and to a lesser extent stainless steel welding with tungsten inert gas is associated with reduced semen quality at exposure in the range of the Danish process specific threshold limit values of welding.     

Two year follow up of pulmonary function values among welders in New Zealand

OBJECTIVES: To examine whether welding is a risk factor for an accelerated decline in pulmonary function. METHODS: 2 Year follow up of pulmonary function and respiratory symptoms among 54 welders and 38 non- welders in eight New Zealand welding sites. RESULTS: There were no significant differences in age, height, smoking habits, ethnicity, or total time in industrial work between welders and non-welders. No overall differences were noted in the changes of pulmonary function variables between the two study groups. However, when the comparison was restricted to smokers, welders had a significantly greater (p = 0.02) annual decline (88.8 ml) in FEV1 than non-welders, who had a slight non-significant annual increase (34.2 ml). Also, welders without respiratory protection or local exhaust ventilation while welding had a greater annual decline both in forced vital capacity (FVC) and forced expiratory volume in one second (FEV1) than welders with protection (p = 0.001 and 0.04, respectively). Among welders a significant association was found between the acute across shift change and the annual decline in FEV1. Chronic bronchitis was more common among welders (24%) than non-welders (5%). Only one welder (2%) but eight non- welders (21%) reported having asthma. CONCLUSIONS: Welders who smoked and welders working without local exhaust ventilation or respiratory protection have an increased risk of accelerated decline in FEV1.

 

     

某汽车制造企业车架焊接工段通风排尘设施除尘效果分析与评价

[目的]评价某汽车制造企业车架焊接工段通风排尘设施的除尘效果,为职业病防治工作提供技术依据。[方法]选择14名电焊工作为个体检测对象,在车间内设置28个检测点,在通风排尘设施使用前后分别对电焊烟尘浓度进行检测;个体采样时间6 h,定点采样时间15 min。对检测结果进行统计学分析。[结果]个体检测中,通风排尘设施使用前后电焊烟尘时间加权平均浓度差异无统计学意义（t=0.107,P=0.916 4）,个体检测超标率的差异无统计学意义（χ2=0.85,P=0.356 6）;定点检测中,通风排尘设施使用前后电焊烟尘短时间接触浓度的差异无统计学意义（t=1.286,P=0.209 4）,检测点超标率的差异无统计学意义（χ2=0.75,P=0.386 5）。[结论]该企业车架焊接工段配备的通风排尘设施未实现预期除尘效果,建议企业对其进行改进,以提高除尘效率,保护劳动者的健康。     

Small airways function in aluminium and stainless steel welders

Summary The effect of welding fumes on small airways was studied in 25 male subjects who welded in aluminium (Al) and to some extent also in stainless steel (SS). Despite a low exposure to welding fumes as compared to the permissible exposure limits, excretion of Al in urine was found to be increased in all subjects (median value: 0.29 mmol/mol creatinine on Friday afternoon, as compared to an upper reference level of 0.10 mmol/mol creatinine). In addition, the welders displayed increased prevalences of work-related eye and airways (pharyngitis and non-specific bronchial hyper-reactivity) symptoms, as compared to 25 matched controls. Short-term welders ( 2.5 years) had more symptoms related to the upper airways than did long-term welders, which may indicate a selection. Spirometry, closing volume and volume of trapped gas (VTG) did not deviate. However, after methacholine inhalation, the long-term welders had a significantly steeper slope of the alveolar plateau on the single-breath nitrogen wash-out test, and a slight increase in VTG, as compared to the short-term welders and the controls. These findings may indicate a welding fume-induced increase in the reactivity of the small airways. Because Al welding was far more frequent than SS welding, an association with the former seems likely.     

镇江市电焊作业工人健康状况调查

目的了解镇江市电焊作业的主要职业病危害对工人健康的影响,掌握镇江市电焊行业职业病危害情况,为制定防治策略提供科学依据。方法对2003—2008年镇江市有电焊行业的企业监测资料及1914人次（共923人）电焊作业人员健康监护资料进行分析。结果作业场所中共有17．4％的电焊烟尘样品浓度超过国家职业接触限值,其中电焊烟尘最高浓度达51．9mg／m^3。健康监护资料显示,心电图异常698人次,占心电图检查总人次的39．0％;胸片异常378人次,占摄片总人次的21．5％,发现疑似电焊工尘肺病人74人次,占摄片总人次的4．2％,摄片时已确诊的电焊工尘肺病人共计36人次,占摄片总人次的2．1％,新诊断出电焊工尘肺50例,检出率为5．8％。结论该市电焊作业危害严重,已直接损害着工人的身体健康,应及时采取切实有效的综合防治措施。     

2012年上海市工作场所电焊烟尘的定量暴露评估

目的］ 了解2012 年上海市工作场所电焊烟尘总尘的暴露水平,分析影响暴露的主要因素。 ［方法］ 开展职业病危害因素主动监测。运用三阶段抽样法抽取178 家各类企业204 个车间的534 名电焊工人作为研究对象,个体采样器呼吸带采样,重量法测定现场空气电焊烟尘总尘的浓度。应用调查问卷现场调查、收集可能影响暴露的因素,运用描述性统计分析、混合效应模型及过量暴露概率对电焊烟尘总尘进行定量暴露评估。 ［结果］ 共获得534 份电焊烟尘样品,浓度检测值呈对数正态分布,几何均数为（1.6±3.9）mg/m3,超标率23.2%。算术均数估算值为4.0 mg/m3,过量暴露概率为0.273。混合效应模型显示,造船行业和金属制造业、大中型企业和室内施焊电焊烟尘暴露水平明显增高（P 〈0.05）;而氩弧焊和良好通风处电焊烟尘暴露水平明显降低（P 〈 0.05）。良好的通风可使同等焊接工艺的电焊烟尘浓度降低34%。 ［结论］ 上海市整体作业场所电焊烟尘暴露水平高,可能会引起较大的健康风险,应优先制定和开展电焊烟尘防控措施。行业、企业规模、焊接工艺种类、通风效果、作业点特征是影响电焊烟尘总尘浓度的主要因素。本研究也证实良好的通风可有效减少电焊烟尘总尘暴露。     

Pulmonary function abnormalities and airway irritation symptoms of metal fumes exposure on automobile spot welders

BACKGROUND: Spot or resistance welding has been considered less hazardous than other types of welding. Automobile manufacturing is a major industry in Taiwan. Spot and arc welding are common processes in this industry. The respiratory effects on automobile spot welders exposed to metal fumes are investigated. METHODS: The cohort consisted of 41 male auto-body spot welders, 76 male arc welders, 71 male office workers, and 59 assemblers without welding exposure. Inductivity Coupled Plasma Mass Spectrophotometer (ICP-MS) was applied to detect metals' (zinc, copper, nickel) levels in the post-shift urine samples. Demographic data, work history, smoking status, and respiratory tract irritation symptoms were gathered by a standard self-administered questionnaire. Pulmonary function tests were also performed. RESULTS: There were significantly higher values for average urine metals' (zinc, copper, nickel) levels in spot welders and arc welders than in the non-welding controls. There were 4 out of 23 (17.4%) abnormal forced vital capacity (FVC) among the high-exposed spot welders, 2 out of 18 (11.1%) among the low-exposed spot welders, and 6 out of 130 (4.6%) non-welding-exposed workers. There was a significant linear trend between spot welding exposure and the prevalence of restrictive airway abnormalities (P = 0.036) after adjusting for other factors. There were 9 out of 23 (39.1%) abnormal peak expiratory flow rate (PEFR) among high-exposed spot welders, 5 out of 18 (27.8%) among the low-exposed spot welders, and 28 out of 130 (21.5%) non-welding-exposed workers. There was a borderline significant linear trend between spot welding exposure and the prevalence of obstructive lung function abnormalities (P = 0.084) after adjusting for other factors. There was also a significant dose-response relationship of airway irritation symptoms (cough, phlegm, chronic bronchitis) among the spot welders. Arc welders with high exposure status also had a significant risk of obstructive lung abnormalities (PEFR reduction). There was also a significant dose-response relationship of airway irritation symptoms (cough, phlegm, chest tightness, and chronic bronchitis) among the arc welders. CONCLUSIONS: These findings suggest that restrictive and obstructive lung abnormalities, and airway irritation symptoms are associated with spot and arc welding exposures.     

Transient changes in the pulmonary function of welders: a cross sectional study of Monday peak expiratory flow.

OBJECTIVES--The aim was to compare the peak expiratory flow (PEF) of welders and non-welders over a 12 hour period from the start of work on Monday. METHODS--The two study groups consisted of 20 welders and 20 non-welders, all men who had essentially never smoked, with no significant difference in age, height, ethnicity, or baseline spirometry between the groups. The PEF was measured for each welder before the start of work and 15 minutes, 30 minutes, and 1, 2, 4, 7, and 12 hours after the start of welding. The same method was applied to the non-welders, for whom a proxy time for the start of welding was used. RESULTS--The percentage change in baseline PEF was calculated for each subject at each of the recording times. The welder and non-welder group means for these results were significantly different at 15 minutes (p = 0.028). Also, the group mean for maximum fall in PEF (at any of the recording times during the 12 hour period) was significantly greater for the welders (p = 0.011). 50% of the welders (10/20), but only 5% of the non-welders (1/20), experienced a fall in PEF in excess of 5% (p = 0.0046). 25% of the welders (5/20) experienced drops of greater than 5% within the first 15 minutes. CONCLUSION--The results are suggestive of an immediate type reaction in welders, similar to that seen in some cases of occupational asthma, although not so severe. Studies to determine if these reactions reflect non-specific bronchial hyper-responsiveness would be useful. It is recommended that future studies also undertake breathing zone measurements to relate the response to particular constituents of the welding plume, especially the gases ozone and nitrogen dioxide.     

Asthma,lung function,and bronchial responsiveness in welders

The incidence of asthma was compared in welders welding in stainless steel (SS) or mild steel (MS). The study was comprised of welders who had been welding for at least 6 months during the preceding 10 year period in four companies, but who had not been welding occupationally prior to this time. The inclusion criteria were met by 42 SS welders with a total welding time of 196 years. Sixteen of these had left work, six because of airway symptoms. Eighty-five MS welders with a total welding time of 403 years were included. Forty-eight of these had left work, 10 citing airway symptoms as a main reason for leaving work, according to responses in a mailed questionnaire. Ex-welders with airway symptoms were in some cases further investigated with spirometry and bronchial provocation tests. In other cases, medical records gave a clear diagnosis. In addition, bronchial responsiveness and lung function were measured and airway symptoms were recorded in presently active welders. Twenty-three of the 26 active SS steel welders and 23 of the 37 active MS steel welders were examined, together with a reference group of 26 (out of 30 invited) vehicle assemblers. There was no difference in the incidence of welding-associated asthma (5% for SS, 7% for MS welders per 1,000 welding-years). Bronchial responsiveness and lung function in active welders was normal and did not differ between MS and SS welders or between welders and a reference group of vehicle fitters. Welders had a significantly higher prevalence of airway symptoms as compared to vehicle fitters.     

小气道功能测定在粉尘作业人员职业健康监护及风险评估中的应用

[目的]了解粉尘作业对员工呼吸功能的影响,探讨小气道功能测定在粉尘作业人员职业健康监护及尘肺风险评估中的应用。[方法]2009年对某机械制造企业粉尘作业车间进行生产环境调查、粉尘浓度检测,对216名粉尘作业人员进行肺功能测定等职业健康检查及问卷调查。[结果]粉尘作业人员用力呼气75％肺活量的瞬间流量（forcedexpiratoryflowat75％offorcedvitalcapacity,FEF75％）的中位数为79％,低于正常值,用力肺活量（forcedvitalcapacity,FVC）、第1秒用力呼气容积（forcedexpiratoryvolumeinonesecond,FEV1）、1秒率（FEVl／FVC）、最高呼气流量（peakexpiratoryflow,PEF）、用力呼气25％肺活量的瞬间流量（forcedexpiratoryflowat25％FVC,FEF25％）、用力呼气50％肺活量的瞬间流量（forcedexpiratoryflowat50％ofFVC,FEF50％）的均数或中位数都在正常范围内,PEF、FEF25％、FEF50％和FEF75％异常的人员比例明显增高,分别为21．30％、BO．56％、45．37％和50．00％,而且这些参数异常人员接尘工龄较短,中位数分别为3．5年、4年、5年和5年。FVC、FEV1、FEV1／FVC、PEF、FEF25％、FEF50％、FEF75％异常人员的胸片检查异常比例分别为55．56％、60％．00、0、21．74％、15．15％、23．47％、25．00％。将胸片异常组与正常组的肺功能进行比较,胸片正常组的PEF、FEF25％、FEF50％的参数值低于异常组,差异有统计学意义（P〈0．05）。工龄10年以上的粉尘作业人员FEV1、FEF25％和FEF75％异常比例高于工龄较短组（P〈0．05）。[结论]粉尘作业人员存在气流受限、小气道功能障碍。随着接尘工龄的增加,FEV1、FEF25％和FEF75％异常人员有增多的趋势。该人群肺功能检查结果与胸片表现并不同步。在职业健康监护工作中,应对粉尘作业人员的肺功能尤其是小气道功能进行重点观察和动态对比分析,并将其作为尘肺风险评估的指标之一。建议在职业健康检查中将FEF25％、FEF50％、FEF75％等反映小气道功能的参数增设为监测指标。     

职业性哮喘患者肺功能变化的临床观察

目的了解职业性哮喘患者的肺功能变化特点。方法对15例职业性哮喘患者行支气管现场激发试验时的肺功能参数进行分析,并同时记录发生时间及患者症状、体征。结果①发作期和激发前肺功能值比较,大部分肺功能参数差异有统计学意义(P0.05)。发作期用力肺活量(FVC)、第1秒用力呼气容量(FEV1)、最大用力呼气流速(PEF)、最大呼气中段流速(MMEF)、25%和50%肺活量时的最大呼气流速(FEF25、FEF50)显著低于激发前;②经直线相关分析,FEV1与FVC下降率之间,FEF50与MMEF下降率之间以及FEV1与MMEF下降率之间均呈直线相关(rs=0.825,P=0.006;rs=0.992,P=0.000;rs=0.881,P=0.004)。③激发后60 min内现场支气管激发试验阳性10例,且全部出现全身发汗、颜面发绀及肺部哮鸣音等严重临床表现,占67%;激发2 h后的现场支气管激发试验阳性5例,占33%。结论职业性变应原致使患者的大小气道功能受限,职业性哮喘可呈速发相反应或迟发相反应。呈速发相反应患者的临床表现明显。     

A mortality study among mild steel and stainless steel welders.

A mortality study was carried out in conjunction with the European mortality study among welders coordinated by the International Agency for Research on Cancer (IARC). The study was aimed at assessing risks for lung cancer in relation to exposure to asbestos, welding fumes containing chromium and nickel, and tobacco smoke. The study included a cohort of 2721 welders and an internal comparison group of 6683 manual workers employed in 13 factories in France. The mortality of the two cohorts was studied from 1975 to 1988 by the historical prospective method. Job histories of welders were traced including welding processes used, metals welded, and proportion of worktime spent in welding. Data on smoking habits were collected from medical records. The observed number of deaths were compared with those expected (standardised mortality ratio (SMR)) based on national rates with adjustments for age, sex, and calendar time. The smoking habits of 87% of the whole study population were known. The distribution of welders and controls according to smoking was not statistically different. The overall mortality was slightly higher for welders (SMR = 1.02, 95% confidence interval (95% CI) 0.89-1.18) than for controls (SMR = 0.91, 95% CI 0.84-0.99). For lung cancer, the SMR was 1.24 (95% CI 0.75-1.94) for welders, whereas the corresponding value was lower for controls (SMR = 0.94, 95% CI 0.68-1.26). The SMR for lung cancer was 1.59 among non-shipyard mild steel welders (95% CI 0.73-3.02). This contrasted with the results for all stainless steel welders (SMR = 0.92, 95% CI 0.19-2.69), and for stainless steel welders predominantly exposed to chromium VI (SMR = 1.03, 95% CI 0.12-3.71). Moreover, SMRs for lung cancer for mild steel welders tended to increase with duration of exposure and time since first exposure, leading to significant excesses for duration > or = 20 years and latency > or = 20 years. Such a pattern was not found for stainless steel welders.