Respiratory symptoms and impairment in shipyard welders and caulker/burners.

All 607 men, aged 17 to 69, comprising a stratified sample of workers from one shipyard completed a respiratory questionnaire, clinical examination, and detailed spirometry. Chest radiographs were available on 332 men. Among the men aged 50-69 the prevalence of persistent cough and phlegm (chronic bronchitis) was 40%, of wheeze on most days 25%, and undue breathlessness on exertion 25%. After allowing for age the relative risk of welders and caulker/burners having these symptoms were respectively 2.8, 2.2, and 3.1 compared with other shipyard tradesmen. The effects were of comparable magnitude to and interacted with those of current smoking. Among the welders and caulker/burners who smoked, the relative risk of developing chronic bronchitis or undue breathlessness was related to the average fume exposure; the relative risk of wheeze was related to the average fume exposure in all smoking categories, with the strongest association in the ex-smokers. The occurrence of wheeze was also associated with a history of previous metal fume fever. A history of pleurisy but not of pneumonia was related to the fume exposure in the welders. After allowing for age and stature, forced expiratory volume (FEV1) was on average higher in young welders (age less than 30) than other tradesmen. In welders and caulker/burners who were current or ex-smokers, FEV1 and PEF were reduced in relation to the average fume exposure (mean reductions respectively 0.25 l and 0.99 l s-1). The FEV1% (of forced vital capacity), the flow rates at small lung volumes (MEF50%FVC and MEF25%FVC), the mean transit time, and its standard deviation were also reduced by fume exposure or the declines with age were increased, or both. No impairment was demonstrable in the non-smokers and many men had given up smoking with apparently beneficial results. The occupational component of the respiratory impairment related mainly to exposures in the past; information was needed on the effects of present conditions in the industry.     

Respiratory symptoms,chronic bronchitis,and ventilatory function in shipyard welders

Summary The prevalence of respiratory symptoms (by standard questionnaire) and the impairment of ventilatory function (vital capacity and FEV_1-O with a bellows spirograph) were investigated in a group of 173 shipyard welders (with more than 5 years experience) in respect to length of exposure and roentgenologic picture. A group of 100 nonwelding shipyard workers served as controls for the prevalence of symptoms. Chronic cough (22%), chronic bronchitis (20%), dyspnea (20%) and wheezing (16%) were more frequent among welders; the difference was significant for the last 2 symptoms only. In contrast, objective (physical) signs were present in equal proportion (14–12%) in both groups. A ventilatory function defect (mostly of the restrictive type) was found in 20% of the welders. The mean FEV_1-0 was significantly decreased in welders with more than 10 years exposure (P相似文献   

Respiratory symptoms in Danish welders

In order to study the effect of welding fumes on respiratory symptoms a cross sectional study was performed in 1982 among 2,660 welders, primarily shipyard welders, compared with a control group of 881 electricians. Only workers more than 34 years of age and in work at the time of the study were selected. Information about respiratory symptoms (using standardized BMRC questions) and exposure was obtained through a self-administered questionnaire. Seventy-four never-smoking welders and 31 never-smoking controls were selected for detailed clinical interviews and extended lung function tests. This article presents the results of the questionnaire study. The welders showed a significantly higher prevalence of chronic bronchitis: 21% versus 9% in the control group (p less than 0.01). The difference could neither be explained by differences in age or smoking habits nor by exposure to other air polluting substances. Other symptoms from the lower and upper respiratory system were also significantly increased among the welders. A dose-response relationship was found between exposure to welding fumes and the prevalence of symptoms from both the upper and lower respiratory system.     

Respiratory health of young shipyard welders and other tradesmen studied cross sectionally and longitudinally.

OBJECTIVE--To assess the effectiveness of current measures for protecting shipyard welders and caulker/burners (WCBs) from the respiratory effects of fumes. METHODS--Shipyard tradesmen born after 1953 (cohort 1), and 181 older men, subjects of a previous study (cohort 2), were assessed, then followed up after an average interval of 6.7 years. The respiratory associations with shipyard trades were assessed cross sectionally and longitudinally and an estimate made of the likely effects of selection bias. Cohort 1 comprised 90% of the 462 eligible WCBs and 239 other tradesmen; there were 31 exclusions. At follow up 139 of 146 men still in the shipyard and 43% of those who had left were reassessed. The lapses were mainly due to migration. All members of cohort 2 were followed up for respiratory symptoms (from MRC questionnaire), were recorded, and indices reflecting all aspects of lung function were measured. RESULTS--At the initial assessment and independent of smoking, trade as a WCB was associated with increased prevalences of chronic cough, phlegm, and wheeze, a reduced transfer factor, and an enhanced age related deterioration in peak expiratory flow (measured cross sectionally). Continued work as a WCB was associated with enhanced deterioration in lung function despite some amelioration of respiratory symptoms; the deterioration was influenced by whether or not exhaust ventilation had been used for every weld. The effects of fume on forced expiratory volume, flow-volume curvilinearity, mean transit time, and moment ratio were independent of and at least as large as those due to smoking. Enhanced deterioration in peak expiratory flow was confined to WCBs who smoked. These effects of trade, but not those of smoking, were nearly independent of atopy. CONCLUSION--In WCBs the working practices over the period of the study did not prevent the development of mild respiratory impairment. In WCBs who used exhaust ventilation at all times, the impairment seemed to reverse by discontinuation of exposure. Thus existing hygiene measures should be applied rigorously. The biological effectiveness of these and any other necessary supplementary measures should be assessed by long term monitoring of forced expiratory volume and peak expiratory flow.     

Respiratory impairment and metal exposure in a group of 68 industrial welders

A group of 68 currently employed welders were examined who were exposed to welding fumes either for the whole or for at least half the working day and who used at least two welding processes, which were mainly manual metal arc welding and metal active gas welding, but also metal and tungsten inert gas welding, or oxyacetylene welding. The welders were classified into 3 groups according to the class of materials used, i.e.: 1) only mild and stainless steel; 2) mild and stainless steel and other metals; 3) only other metals. Chronic bronchitis symptoms were observed in 22% of the subjects; signs of suspected radiological fibrosis were present in 18%, initial signs of radiological fibrosis in 4%. Small airway disease was prevalent in the smokers (28 smokers versus 2 nonsmokers); one worker had an obstructive syndrome and another a restrictive syndrome (both were smokers). There was a good correlation between years of exposure and: 1) MEF25 in non-smokers; 2) urinary cobalt in the whole group. There was also a correlation between smoking and FEV1, MEF50, MEF25, PaO2 and urinary cadmium. Serum copper was higher in workers exposed full time than in those exposed part time. Urinary chromium and cobalt and serum copper were high in steel welders, lower in welders using steel and other metals and low in welders using other metals. Urinary chromium was similar in smokers and non-smokers. Serum zinc was found to be of little use for biological monitoring of welders. Urinary chromium was studied for one week in 10 full-time exposed steel welders. The difference between the chromium values at the end of the workshift and those at the beginning was small (low current exposure); the chromium values at the end of the workshift were not uniform in the whole group (different past exposure levels).     

Lung retention and clearance of shipyard arc welders

Summary The amount of welding fume lung contaminants was measured in 42 shipyard arc welders. The subjects were divided into four groups according to the exposure time which varied from 1 to 40 years. A new measuring method, based on magnetic properties of fume iron retained in the lungs, was used to evaluate the amount of lung contaminants. The average alveolar deposition rate seemed to be from 20 to 40 mg per year, typical alveolar retention after 5 years of continuous exposure was 200 mg and the clearance rate ranged from 10 to 20 % per year.The interindividual variation in the amount of lung dust was high, the geometric standard deviation varying between 2 and 3. The results were compared with post mortem studies of coal miners. Retention rate of welding fumes seemed to be lower than that of coal mine dust but the clearance rate was about the same.     

Grouping schemes of welding fume exposure in shipyard welders

Welding fume exposure can increase the risk of chronic obstructive pulmonary disease (COPD). The aim of this study was to evaluate the optimal grouping schemes of welding fume exposure in shipyard welders for future accurate examination of the association between welding fume exposure and COPD. Industrial hygiene records, including welding fume measurements between 2002 and 2009 were collected from a shipyard. A total of 2,360 personal welding fume measurements was compiled with a geometric mean of 1.66 mg/m³ and a geometric standard deviation of 4.02. Welding jobs were categorized into 8 groups. There were 9 working areas. To obtain the optimal grouping scheme, various grouping schemes were created using job, area, and job^*area combination. To compare various grouping schemes, contrast and precision were calculated for each grouping scheme. For all measurement data, group mean ranking method created by ranking geometric means of the job^*area combination into 3 groups (group mean ranking method) showed the best contrast and precision values among various grouping schemes, followed by grouping based on the job. For a subset of the data excluding job^*area combinations with less than 10 measurements, grouping based on the job showed greater contrast than group mean ranking method, while for other subsets, including only repeated measurement data or further excluding job^*area combinations with less than 10 measurements from the repeated measurement subset, group mean ranking method showed greater contrast than grouping based on the job. Our results showed that group mean ranking or grouping based on the job could be a candidate for the optimal grouping schemes in this shipyard. Our efforts for optimal grouping scheme may aid future cohort study to elucidate the association between welding fume exposure and COPD.     

Respiratory symptoms and pulmonary function in welders of mild steel: A cross-sectional study

Pulmonary function measurements, respiratory symptoms, smoking history, and occupational history were obtained from 91 male welders of mild steel, with mean welding exposure of 108 months, and 80 male factory controls. Nonsmoking welders compared to nonsmoking controls reported higher frequencies of respiratory symptoms and the differences were statistically significant for two symptoms: phlegm, and episodes of cough and phlegm. In comparisons of smoking welders and smoking controls, no significant differences were found in the prevalence of respiratory symptoms. Nonsmoking welders and smoking welders, compared to respective controls, did not have significantly decreased mean values of forced vital capacity or forced expired volume in 1 sec. Mean mid-expiratory flow rates and forced expiratory flow rates at 75% of forced vital capacity were lower, but not significantly different, for welders, compared to controls. These decrements in peripheral flow rates could be trivial or they could represent the initial stages of chronic obstructive pulmonary disease. Long-term follow-up, provided by a large prospective study, is needed to make this distinction.     

Respiratory diseases in arc welders

Summary The prevalence of respiratory symptoms, determined with the Medical Research Council's questionnaire, the impairment of lung function (FVC, FEV₁, FEV%) and the occurence of pulmonary radiographic findings were investigated in a group of 157 electric arc welders and 108 controls. Environmental measurements were made in the workplaces of 88 of the examined welders.The welders had simple chronic bronchitis more often than did the unexposed men (p < 0.01), but no dose-response relationship was found when the prevalence of simple chronic bronchitis was compared with time and level of exposure. The means of the lung function values of the welders with and without simple chronic bronchitis did not differ from each other. The prevalence of mucopurulent chronic bronchitis was the same in the welders and the controls.No significant differences between the two groups were found for lung function, the radiographic findings and the prevalence of respiratory symptoms, except for simple chronic bronchitis. However, the welders reported frequent colds, sore throats, hoarseness and fevers more often than the unexposed men did.     

Small airways dysfunction among non-smoking shipyard arc welders.

Increased volume of trapped gas (VTG), indicating small airways dysfunction, was found among 14 never smoking non-atopic welders who had worked for 10-31 (mean 22) years in their occupation. Spirometry and nitrogen wash out data were compared with those from a reference group of 14 never smoking men not exposed to welding. A methacholine provocation test was carried out. The effect was measured by change in forced expiratory volume in one second (FEV1) and VTG. The maximum decrease in FEV1 after inhalation of methacholine was 6% in welders and 2% among referents. Before provocation VTG and VTG total lung capacity (TLC) was higher among welders (127 ml v 98 ml and 1.76% v 1.38%). The increase in VTG and VTG/TLC was higher in welders after inhalation of methacholine at concentrations of 0.001% to 2% and remained increased after inhalation of salbutamol. The differences indicate small airways disease among shipyard welders.     

Mortality of welders and other craftsmen at a shipyard in NE England

Personnel records of over 1000 welders and electricians but only 235 caulkers and 557 platers employed at a shipyard in NE England between 1940 and 1968 were obtained and the mortality followed up to December 1982. The observed number of deaths (13 from mesothelial tumours, nine among the electricians) were compared with the number to be expected in the Newcastle connurbation. Welders and caulkers were most exposed to welding fumes, electricians to asbestos. The study was limited by the lack of accurate job exposure details, and there was no record of smoking habits, but welders and caulkers showed a higher standardised mortality ratio for all causes, lung cancer, ischaemic heart disease, pneumonia, and accidents than platers and electricians.     

Incidence of cancer among welders and other workers in a Norwegian shipyard

The incidence of cancer among 4778 male shipyard workers, including 783 mild steel welders, was investigated in a historical cohort study. The workers had been employed for at least three months between 1 January 1946 and 31 March 1977. The incidence of cancer was observed from 1 January 1953 through 1986. The loss during follow-up was only 0.9%. There were 53 observed cases of lung cancer in the whole cohort versus 31.3 expected on the basis of the national rates for men. There was an increased incidence of lung cancer among the welders, with seven observed cases versus 3.2 expected. Twenty-two cases of bladder cancer were observed versus 15.2 expected. Two malignant mesotheliomas had occurred (0.7 expected). Smoking was likely to be a confounder in the present study. Due to concomitant exposure to asbestos, the results are inconclusive concerning the possible relationship between exposure to welding fumes and lung cancer.     

Medical wastage in shipyard welders: a forty-year historical cohort study

Summary A 40-year historical cohort study of medical wastage among about 550 shipyard welders and 1100 controls (shipwrights and engine fitters), all employed at the same shipyard, was carried out. The welders left their job 20% more often than the controls; the excess considerably increased with duration of employment. Wastage was particularly due to respiratory, cardiovascular, locomotor and mental disorders. Both welders and controls contributed considerably (about 20%) to permanent work disability. Medical wastage among welders because of respiratory diseases was more than four times higher than among controls, which could not be explained by differential smoking habits alone. The study raises concern about locomotor health hazards for shipyard workers. Moreover, it underscores the need to reduce the large excess risk of respiratory diseases among shipyard welders. The same may be true for welders in other large metal construction plants, e.g. in boiler production.     

Incidence of lung cancer among shipyard welders investigated for siderosis

The incidence of lung cancer among 428 shipyard welders exposed for more than ten years to welding fumes was investigated. The welders were examined for siderosis by the Directorate of Labor Inspection in 1975. The present study was a follow-up based on historical information from the Norwegian registry of dust-exposed workers. Twenty-three welders with siderosis, and 156 welders working at the same shipyards as the siderosis cases were studied as sub-cohorts. There was no loss on follow-up. The observation period was 1976 through 1992. There were 32 cases of cancer from all causes vs 41.3 expected. A nonsignificant excess of lung cancer was observed; 10 cases vs 6.5 expected. The incidence of lung cancer was highest for the welders with more than 30 years since first exposure (7 cases vs 4.1 expected). The sub-cohort of welders with siderosis had no case of lung cancer vs 0.5 expected. These welders were assumed to have experienced high exposure levels for welding fumes. The morbidity of cancer from all causes was low for this small group of blue-collar workers, but the incidence of lung cancer was slightly increased. The increase was not attributable to welders with siderosis. Smoking and asbestos exposure are potential confounders.     

Fluoride exposure and respiratory symptoms in welders

Welders inhale gases and respirable particles. To investigate the relationship between fluoride exposure and respiratory symptoms in welders using basic electrodes containing calcium fluoride, 63 railroad track welders were interviewed. Fluoride was measured in post-shift urine samples. Seventeen welders reported respiratory symptoms related to welding fume exposures. Respiratory symptoms were somewhat more common with increasing concentrations of fluoride in urine. The association between welding fume exposure and respiratory symptoms seems related more to fluorides than to other particles among welders using basic electrodes.     

Mortality of welders and other craftsmen at a shipyard in NE England.

Personnel records of over 1000 welders and electricians but only 235 caulkers and 557 platers employed at a shipyard in NE England between 1940 and 1968 were obtained and the mortality followed up to December 1982. The observed number of deaths (13 from mesothelial tumours, nine among the electricians) were compared with the number to be expected in the Newcastle connurbation. Welders and caulkers were most exposed to welding fumes, electricians to asbestos. The study was limited by the lack of accurate job exposure details, and there was no record of smoking habits, but welders and caulkers showed a higher standardised mortality ratio for all causes, lung cancer, ischaemic heart disease, pneumonia, and accidents than platers and electricians.