Respiratory function and immunological status in workers employed in a latex glove manufacturing plant

A study was performed in 17 female workers employed in a latex glove manufacturing plant. The mean age of these workers was 42 years and the mean duration of their employment was 19 years. The employees were primarily nonsmokers or light smokers. The presence of chronic respiratory symptoms and acute work-related symptoms was recorded for these workers. Ventilatory capacity was measured during the morning work shift by recording maximum expiratory flow-volume curves from which forced vital capacity (FVC), 1-second forced expiratory volume (FEV₁) and maximum expiratory flow at 50%, and the last 25% of the vital capacity (FEF₅₀, FEF₇₅) were measured. A control group of 17 nonexposed women workers was also studied. The prevalence of chronic respiratory symptoms was greater among latex workers than among control confectionry packer workers, varying from 5.9% (vs. 0% in controls) for occupational asthma to 58.8% (vs. 0% in controls) for dyspnea grades 3 or 4. There was also a high prevalence of acute work-related symptoms in this industry, in particular, eye irritation (76.5%), dryness of the nose (70.6%), throat burning (70.6%), dryness of the throat (64.7%), and cough (58.8%). Among exposed workers, measured ventilatory capacity data were significantly lower than among controls, particularly FEF₇₅ (75.1% ± 10.5%). One of the 17 studied workers (5.9%) had a positive skin reaction to latex and had symptoms compatible with occupational asthma. Our data suggest that in addition to occupational asthma, the manufacture of latex gloves is associated with frequent, nonspecific respiratory findings. Am. J. Ind. Med. 33:175–181, 1998. © 1998 Wiley-Liss, Inc.     

Respiratory symptoms and lung function in wool textile workers

Our study investigated a group of 216 wool textile workers (158 women and 58 men). Respiratory symptoms were assessed by questionnaire in wool textile workers and in 130 not exposed (control) workers. Ventilatory capacity was measured in wool workers by recording maximum expiratory flow-volume (MEFV) curves on Monday before and after the work shift. Forced vital capacity (FVC), 1-second forced expiratory volume (FEV₁), and flow rates at 50% and the last 25% of the vital capacity (FEF₅₀, FEF₂₅) were measured on the MEFV curves. Analysis of the data demonstrated a significantly higher prevalence of all chronic respiratory symptoms in wool workers than in controls. being the highest in wool workers for nasal catarrh (M: 63.8%; F: 44.9%) and for sinusitis (M: 62.1%; F: 43.0%). A high prevalence of acute symptoms, associated with the work shift, was also noted in wool workers. Exposure to wool dust caused significant across-shift reductions of ventilatory capacity varying from 1.4% for FEV, to 9.1% for FEF₅₀. Textile workers exposed to wool for > 10 years in the workplace had similar across-shift reductions of ventilatory capacity tests as those with shorter exposures. In a large number of these wool workers, FEF₅₀ and FEF₂₅ were below 70% of predicted normal values. Smokers had acute and chronic lung function changes similar to those of nonsmokers, indicating that smoking did not account for all the respiratory effects seen in wool processing workers. Our data suggest that dust exposures in wool textile mills may be associated with the development of chronic respiratory symptoms and impaired lung function.     

Respiratory function in shoe manufacturing workers

A study of respiratory findings was performed on 376 female workers employed in a shoe manufacturing plant. The mean age of the workers was 32 years and the mean duration of their employment was 12 years. These workers were predominantly nonsmokers. Acute and chronic respiratory symptoms were recorded for each worker, and lung function was measured before and after the work shift. Maximum expiratory flow-volume (MEFV) curves were performed on which forced vital capacity (FVC), 1-second forced expiratory volume (FEV₁), and flow rates at 50% and the last 25% (FEF₅₀, FEF₂₅) were measured. Significantly higher prevalences of all chronic respiratory symptoms were recorded in exposed compared to control workers; in particular, chest tightness (exposed: 44.7%; control: 0%), dyspnea (exposed: 42.6%; control: 2.0%), and rhinitis (exposed: 46.3%; control: 2.4%) were far more prevalent in workers than in controls. Among the shoe workers, there was also a high prevalence of acute symptoms that developed during the work shift, being most pronounced for nose and throat irritation (61.4%). The prevalence of acute and chronic respiratory symptoms increased with duration of employment. Statistically significant across-shift reductions were recorded for all ventilatory capacity tests for the group as a whole. In comparison to predicted, the measured ventilatory capacity parameters were significantly lower for all workers (p < 0.01). Lung function abnormalities increased with duration of employment. Environmental measurements demonstrated that benzene, fur, and synthetic fibers were found at higher than allowable maximal concentrations (Croatian standards). The data suggest that work in the shoe manufacturing industry may be responsible for the development of acute and chronic respiratory impairment. Am. J. Ind. Med. 31:50–55 © 1997 Wiley-Liss, Inc.     

Respiratory findings in synthetic textile workers

We studied 308 female and 92 male textile workers employed in a factory that produced synthetic fiber hosiery. The mean age of the women was 38 years, their mean duration of employment 16 years. The mean age of the men was 39 years with a mean duration of employment of 16 years. A control group of 160 female and 78 male nonexposed workers was also studied. Chronic and acute work related symptoms were recorded for all workers. Ventilatory capacity was measured by recording maximum expiratory flow-volume (MEFV) curves from which the forced vital capacity (FVC), the 1-sec forced expiratory volume (FEV₁) and maximum expiratory flow rates at 50% and the last 25% (FEF₅₀, FEF₇₅) were read. There was a higher prevalence of all chronic respiratory symptoms in exposed than in control workers, although the differences were statistically significant only for dyspnea, sinusitis, and nasal catarrh (P < 0.01) in female synthetic textile workers, and for nasal catarrh (P < 0.01) in male synthetic textile workers. Occupational asthma was recorded in 3 (0.9%) of the women textile workers, and in 1 (1.1%) of male textile workers. There was a high prevalence of acute symptoms during the work shift, which was greatest for cough (female: 46%; male: 59%), dryness of the throat (female: 49%; male: 40%), dryness of the nose (female: 53%; male: 43%) and eye irritation (female: 46%; male: 36%). Ventilatory capacity data among the synthetic textile workers demonstrated significantly decreased FEF₇₅ compared to predicted (P < 0.05). Our data suggest that inhalation of dust in synthetic textile plants causes the respiratory impairment. Am. J. Ind. Med. 33:263–273, 1998. © 1998 Wiley-Liss, Inc.     

Respiratory symptoms and lung function in furriers

Forty women who had been occupationally exposed in the fur coat manufacturing industry were studied. The mean age was 30 years; mean duration of exposure was 14 years. A group of 31 females who did not work in the furrier industry also was included in the study as the control group. A higher prevalence of all chronic respiratory symptoms was found among furriers when compared with controls; these differences were statistically significant for nasal catarrh (p less than 0.05) and sinusitis (p less than 0.01). Among the furriers, the highest prevalence of respiratory symptoms was recorded for chronic cough in 20 workers (50.0%), followed by sinusitis in 12 (30.0%), dyspnea in 10 (25.0%), and nasal catarrh in 8 workers (20.0%). Among the furriers, two (5.0%) had symptoms characteristic of occupational asthma. Most of the symptomatic furriers complained of acute symptoms during their work shifts. Statistically significant mean reductions in lung function over the work shift were recorded in furriers for forced vital capacity (FVC), -4.1%; one-second forced expiratory volume (FEV1), -5.2%; and flow rate at 50% vital capacity (FEF50%), -6.3%. Furriers demonstrated significantly lower mean Monday preshift measurements for FVC and flow rate at 25% (FEF25%) (p less than 0.05) when compared with those predicted. Preshift administration (by spinhaler) of 40 mg disodium cromoglycate in three workers reduced the intensity of acute respiratory symptoms and diminished the reductions in ventilatory capacity over the work shift. Data from six additional male workers demonstrated similar findings for symptoms and lung function. Our data suggest that furriers are at risk of developing both acute and chronic respiratory symptoms as well as ventilatory capacity impairment as a result of occupational exposure.     

Respiratory findings in spice factory workers

The respiratory consequences of working in the spice industry were studied in 92 female spice factory workers (mean age, 36 yr; mean exposure, 12 yr). A control group of 104 female workers employed in a nondusty industry was also studied. The prevalence of chronic respiratory symptoms was significantly higher in the exposed than in the control group. In particular, the prevalence of dyspnea (57.6%), chronic cough (22.8%), chronic phlegm and chronic bronchitis (19.6%), nasal catarrh (37.0%), and sinusitis (22.2%) was high when compared to controls (p less than .01). Among spice factory workers, a high prevalence of acute symptoms during the workshift was recorded. Acute reductions in lung function were statistically significant over the workshift for forced vital capacity (FVC), -2.0%; forced expiratory volume in one second (FEV1.0), -3.0%; and for maximum expiratory flow rates at 50% (FEF50), -8.3% and at 25% (FEF25), -15.2% measured on maximum expiratory flow-volume (MEFV) curves. No difference was found in across-shift ventilatory function in workers with or without chronic respiratory symptoms, except for FEF25 (with symptoms, 16.7%; without symptoms, 9.6%). Preshift administration of 40 mg of disodium cromoglycate (DSC) inhaled 15 min before the workshift significantly diminished acute reductions in FEF50 and FEF25 in exposed workers. Monday preshift FEF50 and FEF25 in exposed workers were significantly lower than in control workers (p less than .01), which suggests an early irreversible component to this illness.     

Respiratory symptoms and pulmonary function in flour processing workers in the baking industry

Respiratory symptoms and ventilatory capacity were studied in 63 flour processing male bakery workers in Umtata, Transkei, Southern Africa. The controls were from a bottling plant in the same city. Both groups were black Africans from the Xhosa-speaking population. The studied population was nonsmoking and no significant difference was noted in age, race, sex, or height between the groups. The exposed workers had significantly lower forced expiratory indices than the control group. Mean percent predicted values of forced expiratory volume in one second (FEV₁), forced expiratory ratio (FEV₁/FVC x 100), forced mid-expiratory flow between 25% and 75% of FVC (FMF), forced expiratory flow between the first 200 ml and 1.200 ml of FVC (FEF 200-1,200), and peak expiratory flow rate (PEF) were, respectively, 11.2%, 20.0%, 31.0%, 27.4%, and 36.1% lower in the exposed group compared with the controls. The prevalence of forced expiratory ratio less than 70% in the exposed group was 37% while in the controls it was 8%. The prevalence of PEF rate less than 5 l/s in the exposed group was 32% while in the controls it was 11%. The exposed workers reported a significantly higher prevalence of respiratory symptoms compared to the controls. The prevalence of nasal symptoms, phlegm, and cough in the exposed workers was 53.9%, 30.1%, and 25.4%, respectively. The present study demonstrated that exposure to flour dust in flour processing workers in the baking industry is associated with significantly lower pulmonary functions and a higher prevalence of respiratory symptoms, and that these workers show signs of airway obstruction, compared to workers not exposed to flour. Flour processing workers have a significant occupationally related respiratory impairment.     

Ventilatory function in brass workers of Gadaladeniya, Sri Lanka

A cross sectional study was conducted to determine the respiratoryhazards of brass workers. The study group was selected randomly.The control group was selected from the general population matchedfor age by cluster sampling. There was a total of 154 pairsfor the final analysis. A questionnaire was administered todetermine the prevalence of respiratory symptoms. Forced vitalcapacity (FVC), forced expiratory volume in the first second(FEV_1.0), forced expiratory flow rate in the mid 50% of theFVC(FEF_25%–75%) and peak expiratory flow rate(PEFR) weremeasured. Chest radiography was performed on those with 5 ormore years of service. Cough, phlegm, chronic bronchitis anddyspnoea were significantly higher among brass workers. Theventilatory capacity was significantly lower in all the indicatorsexcept FVC. Smoking had no significant effect and a dose responserelationship could not be demonstrated after inclusion of agein the regression model. Five point five per cent had evidenceof septal lines while 6.4% had emphysema.     

Respiratory Health of Plywood Workers Occupationally Exposed to Formaldehyde

This study was undertaken to enlarge our understanding of the adverse health effects of formaldehyde exposure in the workplace and community environment. The respiratory health status of 186 male plywood workers was evaluated by spirometric tests, respiratory questionnaires, and chest x-rays. Area concentrations of formaldehyde were measured in the work environment and found to range from 0.28 to 3.48 ppm. The average personal exposure was to 1.13 ppm of formaldehyde. Exposure to formaldehyde was associated with decrements in the baseline spirometric values, i.e., forced expiratory volume in 1 sec (FEV_(1.2) forced expiratory volume/forced vital capacity (FEV/FVC), and FEF_25%-75%, and with several respiratory symptoms and diseases, including cough, phlegm, asthma, chronic bronchitis, and chest colds. The results of the study support the hypothesis that chronic exposure to formaldehyde induces symptoms and signs of chronic obstructive lung disease.     

Respiratory symptoms in fish processing workers on the Adriatic coast of Croatia

This article describes respiratory symptoms and lung function in 98 fish processing female workers employed in a fish processing plant located on the Croatian Adriatic coast and 95 matching controls. The study included chronic and acute respiratory symptoms which developed during the shifts. Lung function measurements included forced vital capacity (FVC), one-second forced expiratory volume (FEV(1)) and maximal expiratory rates at 50 % and the last 25 % (FEF(50), FEF(25)). Chronic respiratory symptoms were significantly dominant in fish processing workers compared to controls. The most common chronic symptoms were hoarseness (57.1 %), nasal catarrh (51.0 %), chronic cough (42.9 %), chronic phlegm (34.7 %), and frequent chest cold (35.7 %). Exposed smokers and nonsmokers had a similar prevalence of chronic respiratory symptoms. Acute symptoms over the work shift were high, with headache in lead (smokers: 62.5 %; nonsmokers: 56.1 %). Most of the ventilatory capacity parameters were significantly lower than predicted, FEF(25) in particular, indicating obstructive changes predominantly in the smaller airways. These findings suggest that fish processing workers are prone to developing acute and chronic respiratory symptoms as well as to lung function changes. This calls for medical and technical preventive measures to be introduced in the work environment of the fish processing plant.     

Relative chronic effects of different occupational dusts on respiratory indices and health of workers in three Ethiopian factories

The respiratory effects of dusts in different sections of yarn, cement, and cigarette factories were studied in 211 nonsmoking male and female workers aged 21–57 years. The controls used were 211 healthy nonsmoking and nonexposed male and female subjects aged 20–57 years from the general population. Forced vital capacity (FVC), forced expiratory volume in 1 sec (FEV₁), FEV₁/FVC ratio, forced expiratory flow (FEF_{200–1,200 ml}), forced mid-expiratory flow (FMF_25–75%) and peak expiratory flow rate (PEFR) were recorded in all subjects with and without respiratory symptoms. Taking exposures to all dusts of different concentrations together, it was found that the frequency of respiratory illness was greater among exposed workers (40.5% in males, 36% in females) than it was among controls (21.6% in males,18% in females). In exposed subjects, the symptom prevalence was only 4.5% higher in males than in females.The mean lung function indices, including FEV₁, FEV_1%, FEF_{200–1,200 ml}, FMF_25–75%, and PEFR, in subjects exposed to all dusts in general decreased markedly, with dust concentration being more important than duration of exposure, and FMF being affected slightly more consistently. About 38.4% of the dust-exposed subjects developed corresponding respiratory illnesses including chronic cough (24.7%), chronic bronchitis (21.8%) and bronchial asthma (24.2%). The respective control values were 9.0%, 9.5%, and 8.5%. Exposure to different occupational dusts resulted in the development of respiratory illness with different rates of prevalence. The effects of exposure to cotton and cement dusts on respiratory health of exposed subjects were relatively more significant (p < 0.001) than that of exposure to tobacco dust (p < 0.05). Am. J. Ind. Med. 34:373–380, 1998. © 1998 Wiley-Liss, Inc.     

Ventilatory function and allergic skin tests in cotton mill workers

Ventilatory capacity, chronic respiratory symptoms and respiratory diseases as well as intradermal skin tests were registered in a group of 112 cotton workers. The prevalence of chronic respiratory symptoms and respiratory diseases was higher among the exposed than among control workers although the differences were statistically significant only for chronic cough, nasal catarrh and byssinosis in women and for chronic cough, chronic phlegm and byssinosis in men. A similar prevalence of byssinosis was noted in women (29.4%) and in men (29.5%). Among textile workers mostly byssinosis grade 1/2 was found (women 22.1%, men 20.5%). There were statistically significant acute reductions over work shift for forced vital capacity (FVC) and one-second forced expiratory volume (FEV1). In men the values were somewhat lower than the expected normal values. A very small number of workers demonstrated positive intradermal skin tests to cotton allergen (exposed 8.2%, control 1.8%). Our data indicate that exposure to cotton dust may lead to the development of respiratory symptoms and diseases as well as to acute changes in ventilatory capacity but without an allergic reaction.     

Chronic Respiratory Effects of Exposure to Diesel Emissions in Coal Mines

A 5-yr prospective design was employed to test the hypothesis that exposure to diesel emissions leads to chronic respiratory effects among underground coal miners. Changes in respiratory function and development of chronic respiratory symptoms were measured during a 5-yr study period (i.e., 1977 to 1982) in 280 diesel-exposed and 838 control miners from Eastern and Western United States underground coal mines. Spirometry measures of respiratory function included forced expiratory volume in 1 sec (FEV, _1.0), forced vital capacity (FVC), and forced expiratory flow rate at 50% of FVC (FEF₅₀). Chronic respiratory symptom measures, which included chronic cough, chronic phlegm, and breathlessness, were obtained by questionnaires, as were smoking status and occupational history. Based upon these data, the pattern of evidence did not support the hypothesis either in an age-adjusted comparison of diesel vs. nondiesel miners or in an internal analysis by cumulative years of diesel exposure.     

Medical and industrial hygiene characterization of the cotton waste utilization industry

We studied 260 workers in the cotton waste utilization industry and 310 "blue-collar" control workers from nondusty industries in the same geographic area of the United States by respiratory symptom questionnaire and by pre- and postshift spirometry. We excluded 75 cotton workers and 75 control workers from statistical analysis because of prior hazardous occupational exposures. Plant-wide, 8-hour time-weighted average exposures ranged from 0.28 mg/m3 to 7.80 mg/m3. The overall prevalence of symptoms compatible with byssinosis was 5.9% in cotton workers and 4.7% in the controls. Cotton workers with less than 2 years of employment had a significantly greater prevalence of bronchitis than their control counterparts. The cotton workers with 2 years or more of employment had significantly greater prevalences of bronchitis, shift decrement in forced expiratory volume in 1 second (FEV1) of greater than or equal to 10%, and FEV1/FEV1-predicted less than 80%, than their control counterparts. Regression analysis showed that for matched cotton and control workers, the percentage decrement in FEV1 over the shift was significantly greater for cotton workers; and that in all cotton workers, longevity in industry had a negative effect on the before-shift forced vital capacity (FVC). This study suggests that there are both acute and chronic effects of cotton exposure in the cotton waste utilization industry.     

Respiratory function in vineyard and orchard workers

A group of 174 male vineyard and orchard workers was studied for the prevalence of acute and chronic respiratory symptoms and lung function changes. In addition, 115 male control workers were studied for the prevalence of chronic respiratory symptoms. There was a significantly higher prevalence of dyspnea and chest tightness in exposed compared to control workers. In particular, exposed nonsmokers had significantly higher prevalences of dyspnea and chest tightness than controls; this was found for exposed nonsmokers with both short (≤10 years) and long (>10 years) exposure. Smokers exposed for more than 10 years had significantly higher prevalences of chronic cough, chronic phlegm, chronic bronchitis, and chest tightness than smokers with shorter exposures (p < 0.01 or p < 0.05). Workers employed for more than 10 years had higher prevalences of most of the acute (shift-related) symptoms than those workers with shorter employment; however, the differences were significant only for cough in smokers (p < 0.05). Significantly lower than predicted FVC values were measured in smokers and nonsmokers after both short and long duration of employment. Differences between measured and predicted FEV₁, FEF₅₀, and FEF₂₅ were significant for workers employed for more than 10 years. A separate analysis of individual data as a percent of predicted values demonstrated that many workers had FVC (5.2%), FEV₁ (6.3%), FEF₅₀ (27.6%), and FEF₂₅ (40.2%) lower than 70% of predicted values. These data suggest that vineyard and orchard workers may develop acute and chronic respiratory symptoms and lung function changes which are, in part, related to environmental factors and to cigarette consumption. Am. J. Ind. Med. 31:250–255, 1997. © 1997 Wiley-Liss, Inc.     

Follow-up study of respiratory function in Hemp workers

A 3-year follow-up study was performed on 38 women and 28 men from the originally studied textile workers employed in a soft hemp processing mill. Acute and chronic respiratory symptoms and ventilatory capacity were recorded during the cross-sectional and the follow-up studies. Maximum expiratory flow-volume (MEFV) curves were obtained on these workers, and forced vital capacity (FVC), 1-second forced expiratory volume (FEV₁) and flow rates at 50% and at 25% of the VC (FEF₅₀, FEF₂₅) were measured. High prevalences of acute and chronic respiratory symptoms persisted at the follow-up study. In particular, high prevalences of byssinosis were documented at both studies (women: 47.4% and 47.4%; men: 64.3% and 67.9%, respectively). Statistically significant mean across-shift reductions were recorded for all ventilatory capacity tests at the initial study. A large mean annual decline was calculated for FEV₁ in women and for all ventilatory capacity parameters in men; these declines were greater for workers with symptoms of byssinosis than for those without. The accelerated decline in FEV₁ noted in the women workers, who were predominantly nonsmokers, suggests an independent hemp effect. Exposures in the work environment were measured with Hexhlet filters and revealed very high dust concentrations (mean total: 21.4 mg/m³, 22.4 mg/m³; respirable: 8.4 mg/m³, 9.9 mg/m³) at both initial and follow-up studies. These levels are much higher than those found in mills processing organic materials in North America. Our data demonstrate that work in the hemp industry, particularly in small poorly regulated mills, continues to have deleterious effects on respiratory function.     

Pulmonary function in Sardinian fire fighters

Our study examined the respiratory function of 92 firemen whose main activity is fire fighting in forests and open country. Such fire fighting activities are to be considered a risk to the respiratory tract, taking into account studies already in the literature that have evaluated the nature and quantity of inhalable toxins present in activities of this kind. The control group was composed of 51 Carabinieri (policemen), who were asked to fill in a questionnaire about their work activities. Forced expiratory volume and flow, total lung capacity, respiratory volume, and the permeability of the alveolar-capillary barrier were measured. Firemen and Carabinieri (policemen) showed FVC rates higher than the European Community for Coal and Steel standards. The firemen showed a significant reduction in forced expiratory volume in 1 second (FEV₁) [3.90 (0.50) vs. 4.04 (0.44); p < 0.05] and forced expiratory flow at 75% of forced vital capacity (FVC) (FEF₇₅) [8.37 (4.11) vs. 8.38 (1.67) p < 0.05] and more markedly in the FEV₁/FVC relationship [80.07 (5.89) vs. 83.89 (1.67) p < 0.001] and in FEF₅₀ [4.73 (1.34) vs. 5.54 (1.44) p < 0.01] and FEF₂₅ [1.58 (.47) vs. 1.99 (.69) p < 0.001]. There were no marked differences in air-blood exchanges. No correlation was found between respiratory function data and years of service or the number of fires extinguished during work experience. © 1996 Wiley-Liss, Inc.     

Ventilatory function of factory workers exposed to tea dust

A cross-sectional study was conducted in order to determinethe prevalence of respiratory symptoms and the effect on ventilatorycapacity in workers exposed to tea dust for at least five yearsduring the sifting process of tea manufacture compared to acontrol group of field workers who were not exposed to tea dustpreviously. Fifty-three subjects each in the study and controlgroups were matched for age, sex, ethnic group and height. Prevalenceof chronic respiratory symptoms was obtained by questionnaire.Spirometric measurements included forced vital capacity (FVC),forced expiratory volume in the first second (FEV_1.0) and forcedmid-expiratory flow rate (FEF_25–75%). The study grouphad a chest radiograph. The odds ratio for any chronic respiratorysymptom was 11.6 (95% confidence interval [Cl] = 3.7–39.4)in the study group. Mean values for the spirometric tests werelower in the study group; the differences in FEV_1.0 and FEF_25–75%were significant. Tuberculosis was not found in the study group,while one subject (2.4%) had radiological evidence of bronchiectasis.It may therefore be concluded that chronic tea dust exposurecauses increased prevalence of respiratory symptoms and a significantdegree of small airways obstruction.     

Respiratory function and immunological reactions in jute workers

A prospective study of respiratory function was performed in a group of 70 jute and 40 control workers. At the initial study there were consistently higher prevalences of all chronic respiratory symptoms in jute workers compared to control workers; however, the differences were statistically significant only for dyspnea (P < 0.05). At the follow-up study 19 out of the original 70 jute workers were examined 19 years later. There was a significant increase in the prevalence of almost all chronic respiratory symptoms among these workers. Similar across-shift reductions of forced vital capacity (FVC) and the 1-s forced expiratory volume (FEVI) were recorded on Monday and the following Thursday at the initial study. In the 19 jute workers followed prospectively there were similar across-shift reductions of FVC and FEVI at the first and the follow-up study, the reduction being slightly larger for FEV₁ than for FVC. Only one jute worker (5.3%) and two control workers (5.7%) responded to skin testing with specific textile extracts. Two workers developed symptoms of occupational asthma. One of these workers had a positive response to skin testing with jute extract. Our data suggest that exposure to jute dust may cause the development of chronic respiratory symptoms in some workers.     

Annual decline of ventilatory capacity and change in acute respiratory response in hemp exposure over a 10-year period

Summary A follow-up study of the effect of exposure to hemp dust on respiratory function over a 10-year period (1963–1973) was conducted in 24 female non-smoking hemp workers. The prevalence of byssinosis in 1973 (70.8%) was found to be significantly higher than 10 years earlier in 1963 (33%) (P<0.01). The prevalence of all other chronic respiratory symptoms was also considerably increased. In the control group the prevalence of all chronic respiratory symptoms was practically the same during both surveys.In hemp workers, there was a significant acute fall over the work shift in FEV_1.0 (1-second forced expiratory volume) and FVC (forced vital capacity), both in 1963 and 1973 (P<0.01), except in the group of workers who did not have byssinosis either in 1963 or in 1973. The lowest mean annual decline of FEV_1.0 within the 10-year period was found in the group without byssinosis in both 1963 and in 1973 (27 ml), followed by the group without byssinosis in 1963 but with byssinosis in 1973 (38 ml). The largest annual decline was observed in the subjects with byssinosis during both surveys (55 ml). The mean annual FEV_1.0 decline in the control group was 22 ml.