Respiratory problems among cotton textile mill workers in Ethiopia.

This study was conducted to investigate the prevalence of respiratory problems, in particular byssinosis, and to explore factors associated with their occurrence among a group of 595 randomly selected workers representing 40.5% of those exposed to dusty operations in a typical Ethiopian cotton textile mill. A standard questionnaire on respiration was administered and pre and postshift forced vital capacity (FVC) and forced expiratory volume in one second (FEV1) were determined for each worker; workers found to have byssinosis and other respiratory diseases were compared with workers having no respiratory diseases in terms of the level and duration of exposure to cotton dust and other variables. Multiple area air samples from different sections were analysed for elutriated cotton dust concentrations (0.86-3.52 mg/m3). The prevalence of byssinosis was 43.2% among blowers and 37.5% in carders in comparison with four to 24% among workers in other sections. Prevalence of chronic bronchitis ranged from 17.6 to 47.7% and bronchial asthma from 8.5 to 20.5% across all sections. Significant across shift decrements in FEV1 and FVC were seen in those workers with respiratory tract diseases compared with those workers without such diseases. A significant dose response relation for pulmonary function and respiratory illnesses was also found by regression analysis. Preventive measures are proposed. Further research including a nationwide survey of textile mills is suggested. This is the first epidemiological study of the textile industry in Ethiopia.     

Hypertension among cotton textile workers

The present cross sectional study on prevalence of hypertension was carried out among 514 cotton textile workers of Shri Bapurao Deshmukh Sut Gimi, Wardha. Using standard guidelines for measuring blood pressure and standard criteria for diagnosis of hypertension, 20.2% of the subjects were found to have raised systolic and/or diastolic blood pressure. The prevalence of hypertension was significantly higher among persons aged 35 years or more, in the present occupation for 10 years or more and those working in more noisy department.     

Respiratory disorders and atopy in cotton, wool, and other textile mill workers in Denmark.

A cross-sectional study of respiratory disorders and atopy in Danish textile industry workers was conducted to survey respiratory symptoms throughout the textile industry, to estimate the association of these disorders with atopy, and to study dose-response relationships within the cotton industry. Workers at cotton mills, a wool mill, and a man-made fiber (MMF) mill were examined. Four hundred nine (90%) of the 445 workers participated in this survey, i.e., 253, 62, and 94 workers at the cotton mills, the wool mill, and the MMF mill, respectively. An interview designed to assess the prevalence of common respiratory and allergic symptoms was given to all workers willing to participate, and blood samples were drawn. Lung function measurements determined a baseline FEV1, FVC and the change in FEV1 and FVC during work hours on a Monday. The working environment was examined for dust, bacteria, endotoxins, and molds, and the exposure was estimated for each participant. The mean personal samples of airborne respirable dust and respirable endotoxin were highest in the cotton industry, i.e., 0.17-0.50 mg/m3 and 9.0-126 ng/m3 respectively, whereas mold spores were found in the highest concentrations in the wool mill: 280-791 colony-forming units (cfu)/m3. Only small concentrations of microorganisms were found in the MMF mill. The mean change in FEV1% and FVC% was greatest among atopic individuals in both cotton and wool industry and other textile industries although the differences were not significant. FEV1% and FVC% in the cotton workers were significantly associated with the cumulative exposure to respirable endotoxin. Byssinosis was diagnosed only in the cotton industry. We found a dose-response relationship between endotoxin exposure and byssinosis, and a significant association between A-1-A serum concentrations less than or equal to 35 mumol/liter and byssinosis, a finding we are further evaluating in subsequent studies.     

Mortality and disability among cotton mill workers

The mortality and disability of cotton mill workers were studied in five Finnish cotton mills. The population under study comprised all 1065 women exposed to raw cotton dust who had been hired between 1950 and 1971. The minimum exposure period was five years. For the study on disability, the cohort was followed up until the end of 1981. The follow up period for the mortality analysis was from 1950 to 1985. At the end of 1981 the observed number of prevalent disability pensions for respiratory disease was 15, whereas 3.9 were expected (p less than 0.01) on the basis of the national figures for women. There were 46 musculoskeletal diseases (27.7 expected, p less than 0.01), of which 24 were osteoarthritis (14.5 expected) and 13 rheumatoid arthritis (6.6 expected). The incidence rates of disability pensions were calculated for the period 1969-81. Comparison of incidence rates between cotton mill workers and the Finnish female population showed excessive rates for both respiratory diseases (p less than 0.001) and musculoskeletal diseases (p less than 0.01), with an excess of new cases of rheumatoid arthritis (p less than 0.05). By the end of 1985 the number of person-years was 31,678 and the number of deaths 95. The standardised mortality ratios for the total period of follow up (1950-85) showed no excess for respiratory diseases. Mortality from cardiovascular diseases was also lower than expected. The observed number of tumours was 33, the corresponding expected number 32.0. Thirteen tumours were in the digestive organs (6.6 expected, p<0.05) and three were lung cancers (1.9 expected). Five workers had died from renal disease; the expected number was 1.5 (p<0.05).     

Mortality and disability among cotton mill workers.

The mortality and disability of cotton mill workers were studied in five Finnish cotton mills. The population under study comprised all 1065 women exposed to raw cotton dust who had been hired between 1950 and 1971. The minimum exposure period was five years. For the study on disability, the cohort was followed up until the end of 1981. The follow up period for the mortality analysis was from 1950 to 1985. At the end of 1981 the observed number of prevalent disability pensions for respiratory disease was 15, whereas 3.9 were expected (p less than 0.01) on the basis of the national figures for women. There were 46 musculoskeletal diseases (27.7 expected, p less than 0.01), of which 24 were osteoarthritis (14.5 expected) and 13 rheumatoid arthritis (6.6 expected). The incidence rates of disability pensions were calculated for the period 1969-81. Comparison of incidence rates between cotton mill workers and the Finnish female population showed excessive rates for both respiratory diseases (p less than 0.001) and musculoskeletal diseases (p less than 0.01), with an excess of new cases of rheumatoid arthritis (p less than 0.05). By the end of 1985 the number of person-years was 31,678 and the number of deaths 95. The standardised mortality ratios for the total period of follow up (1950-85) showed no excess for respiratory diseases. Mortality from cardiovascular diseases was also lower than expected. The observed number of tumours was 33, the corresponding expected number 32.0. Thirteen tumours were in the digestive organs (6.6 expected, p<0.05) and three were lung cancers (1.9 expected). Five workers had died from renal disease; the expected number was 1.5 (p<0.05).     

Byssinosis and serum IgE concentrations in textile workers in an Italian cotton mill

ABSTRACT The relationship between serum concentrations of total IgE and byssinosis and other respiratory symptoms was evaluated in 352 textile workers (90 men, 262 women) at a cotton mill in Friuli-Venezia Giulia, Italy. The subjects were aged from 20 to 61 (mean 44) and the mean duration of employment was 20 years. One hundred and eight subjects (30·7%) were smokers. Only 2% had a positive history of atopy. A standardised questionnaire showed chronic bronchitis in 96 textile workers (27·3%) and byssinosis in 63 (17·9%). The prevalence of respiratory disorders was the same for men and women but was higher in the carding room than in other work areas. Total serum IgE concentrations (RIST, Phadebas) were analysed after log transformation. The geometric mean was 192·7 IU/ml, with no significant difference between the two sexes. This mean concentration of IgE is much higher than that reported internationally for non-atopic subjects, but similar to values found in the Italian population. The IgE concentrations of the workers in the main departments (carding, spinning, and weaving) showed no significant difference. The geometric means were not different in subsamples stratified according to respiratory diseases (cases of pure and cases of mixed forms of chronic bronchitis and byssinosis). A negative result was obtained when IgE concentrations of 289 subjects without byssinosis (¯x = 188·4 IU/ml) and 63 with byssinosis (¯x = 212·6 IU/ml) were compared; there was also no trend when the results were analysed by clinical grade of byssinosis. The same negative pattern occured when the serum IgE concentrations were examined in patients with byssinosis with different grades of chronic change in FEV₁. The results of this study support the hypothesis that there is no relationship between total serum IgE concentrations and byssinosis.     

Respiratory function of textile workers employed in dyeing cotton and wool fibers

A group of 135 textile dyeing workers (97 male and 38 female) was studied for the prevalence of acute and chronic respiratory symptoms and lung function changes. Respiratory symptoms were elicited by a standardized questionnaire, and lung function testing was performed before and after the morning shift by recording maximum expiratory flow-volume (MEFV) curves. In addition, 103 nonexposed control workers were studied. The prevalence of all chronic respiratory symptoms was significantly higher in the exposed than in the control workers; in particular, the prevalence of occupational asthma was 6%. The exposed nonsmoking workers had more complaints than the controls who were nonsmokers. As expected, most of the symptoms were more prevalent in smokers than in nonsmokers. Nonsmokers with both long- and short-term work exposure had higher prevalences of dyspnea and rhinitis than control workers. Smokers exposed for 10 years or less had significantly higher prevalences of chronic phlegm than nonsmokers with the same duration of exposure (p < 0.05). In workers exposed for >10 years, there were significantly higher prevalences of chronic cough, chronic phlegm, and chronic bronchitis in smokers than in nonsmokers (p < 0.01). A high prevalence of shift-related symptoms was found in exposed workers. Significant across-shift reductions of ventilatory capacity tests were documented in this cohort and varied from an average of 4.0% for FVC to 14.2% for FEF₂₅. Preshift values of ventilatory capacity were significantly lower in this exposed population compared to predicted values suggesting a chronic effect. Our data suggest that textile dyeing workers develop acute and chronic respiratory impairment as a result of their exposures. These findings are exacerbated by cigarette smoking. Am. J. Ind. Med. 31:344–352, 1997. © 1997 Wiley-Liss, Inc.     

Respiratory disease in cotton textile workers in the People's Republic of China. I. Respiratory symptoms

The prevalence of byssinosis and nonspecific respiratory symptoms was studied in 887 textile workers with at least two years of employment in two cotton mills and one silk mill in Shanghai, the People's Republic of China. A standardized respiratory questionnaire was used, and environmental sampling was performed with vertical elutriators and colorimeter grading. Eight percent of the cotton textile workers complained of byssinosis. The reports of byssinosis were mostly mild (grade 1/2), more prevalent among women, and unrelated to duration of employment or elutriator dust levels. Nonspecific respiratory symptoms were significantly more prevalent among cotton textile workers than silk workers. After adjustment for age, gender, and smoking in logistic regression models, the odds ratios for the effect of working in cotton textile mills on chronic bronchitis, chronic cough, and frequent chest illness were 3.3, 2.9 and 4.7, respectively. Although none of the symptoms were related to current dust levels, the range of exposures was narrow, and information was only available on current levels of cotton dust. This study represents the first respiratory survey of the textile industry in China using diagnostic criteria similar to that used in the United States and England; it defines a cohort for prospective investigation.     

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.     

Pulmonary function and morbidity in textile mill workers.

The study was conducted in a large cotton textile mill in Surat City. A selected number of 278 employees were evaluated for social, anthropological and pulmonary functions. No parameters except the period of exposure to dust reduced pulmonary function; it was statistically significant in the case of vital capacity and maximum breathing capacity. Out of 23.94% pulmonary morbidity observed, the byssinosis rate was 1.62.     

Respiratory and allergic symptoms in wool textile workers

An epidemiological study of 2153 workers in 15 West Yorkshire wool textile mills was conducted to determine relations between respiratory symptoms and exposure to inspirable wool mill dust. A questionnaire designed to elicit all the common respiratory symptoms was developed and tested, and administered to all workers willing to participate (85%). It was translated and administered in Urdu for the 385 workers from Pakistan whose English was not fluent. Symptoms investigated included cough and phlegm, wheezing and chest tightness, breathlessness and its variability, rhinitis, conjunctivitis, chills, nosebleeds, and chest illnesses. Additional questions were asked, where appropriate, about the times of day, days of the week, seasons, and places that the symptoms were worse or better than normal. An environmental survey was carried out at each mill, which included 629 measurements of inspirable dust, enabling estimates to be made of the airborne concentrations of inspirable dust usually experienced by each member of the workforce under current conditions. Overall symptom prevalences were: persistent cough and phlegm, 9%; wheeze, 31%; breathlessness on walking with others on level ground, 10%; persistent rhinitis, 18%; persistent conjunctivitis, 10%; persistent chills, 2%; ten or more nosebleeds a year, 2%; and three or more chest illnesses in past three years, 5%. After allowing for the effects of age, sex, smoking habit, and ethnic group, cough and phlegm, wheeze, breathlessness, rhinitis, conjunctivitis, and nosebleeds were found to be more frequent in those exposed to higher than to lower concentrations of dust. In some experiencing high concentrations (blenders and carpet yarn backwinders) cough and phlegm, wheeze, rhinitis, and conjunctivitis were related to the years worked in such jobs. Relative risks of each symptom in relation to inspirable dust concentrations were calculated by means of a logistic regression analysis. At concentrations of 10 mg/m3, the current United Kingdom standard for nuisance dusts, the risk of cough and phlegm relative to that of an unexposed worker was 1.37, that of wheeze 1.40, breathlessness 1.48, rhinitis 1.24, and conjunctivitis 1.70. Since some of these symptoms may be associated with functional impairment of the lungs, further studies of selected workers are being carried out to estimate the functional effects of exposure to dust in wool textile mills.     

Across-shift changes of exhaled nitric oxide and spirometric indices among cotton textile workers

Objectives

For the purpose of evaluation of exhaled NO as an index of airway inflammation, we assessed changes in fractional exhaled NO (FeNO) across a work shift and its relationship with respiratory complaints.

Material and Methods

Chronic and work-aggravated respiratory complaints were assessed using a questionnaire in 89 male textile workers. FeNO and spirometry were performed before and after a work shift and all the changes were registered.

Results

A significant increase in FeNO after a work shift was observed. Post-shift FeNO was significantly higher among the subjects with chronic respiratory complaints. There was an obvious decrease in FVC, and FEV₁ after a work shift; however, we couldn’t find a significant relationship between changes in respiratory parameters and concentration of inhalable dusts.

Conclusions

FeNO increase after a work shift along with pulmonary function decrement and higher post-shift FeNO among subjects with respiratory complaints makes across-shift FeNO a non-invasive test for assessment of airway hyper-responsiveness in textile workers.     

Respiratory function and bronchial reactivity in mill workers

Professional exposure to vegetable dusts affect the respiratory function of the exposed subjects. A previous survey conducted in an industrial flour-mill demonstrated a higher frequency of respiratory symptoms in workers compared to a control group. Ten subjects employed in a work site particularly exposed to dust were studied. Each subject answered a questionnaire and performed on Mondays and Fridays, at the begenning and end of his work shift, a flow volume curve and an isocapnic hyperventilation test. The aerobiology of the professional environment was also measured. We noted: 1) in the flow volume curves: a drop in the FEV₁ during the Monday morning shift, a significant difference between the FEV₁ (p<0.05) and the MMEFR 25–75 (p<0.05) measured at 6 am on Monday and Friday, and between the MMEFR 25–75 values obtained at 12 noon on Monday and Friday (p<0.05). 2) after isocapnic hyperventilation, a significant drop in the MMEFR 25–75 at 6 am on Monday (p<0.01) and in the FEV₁ and MMEFR 25–75 at 12 noon on Mondays (p<0.05), a significant drop in the FEV₁ at 1 pm on Monday (p<0.01).     

Mortality from byssinosis among New England cotton mill workers, 1905-1912

Little was known about mortality from byssinosis among American cotton mill workers until recent times. Between 1912 and 1919, the Labor Department published two detailed investigations of mortality by cause of death among cotton mill workers and other residents of several New England mill towns. Statistical tests reveal no significant difference in mortality rates from nontubercular respiratory diseases between cotton textile workers and other mill town residents. Even when ex-mill workers who may have died from mill-related respiratory ailments are added to work-related deaths and subtracted from the control group, mortality rates do not differ significantly. Finally, when mortality rates for workers in the most dusty areas of the mills--picking and carding--are compared with those of other Fall River, Mass., residents, the differences are still not statistically significant. Apparently byssinosis was not a cause of excess mortality among New England cotton mill workers at the turn of the century.     

Meta-analysis of standard mortality ratio in cotton textile workers

Background: Pulmonary function tests may reveal obstructive lung disease with altered forced expiratory volume in 1 s (FEV₁) in cotton textile workers. Since 1930, many cohort studies have been performed to assess the disease mortality rate in cotton textile workers. Materials and methods: The authors performed a meta-analysis of the SMR results of these studies. Results: From the meta-analysis, the SMRs were as follows: for all deaths, 0.792 in males and 0.873 in females; for cancers, 0.705 in males and 0.829 in females. Discussion: The male cotton textile workers were healthier than the general population. The healthy-worker effect may be one of the causes, in general workers in industry have a better mortality patterns than those not working.     

Immunological findings and respiratory function in cotton textile workers

Summary Immunological parameters were studied in a group of 24 cotton textile workers. These were volunteers from a cohort of 106 (83 women and 23 men) previously studied textile workers. A group of 30 employees from a bottle packing plant served as a control for the immunologic studies. The subgroup of volunteers undergoing immunologic testing did not differ from the original cohort of textile workers in age, sex, smoking history, or prevalence of most chronic respiratory symptoms, nor were there any significant differences in baseline lung function or across-shift changes. The 24 cotton worker volunteers underwent skin testing with extracts of cotton dust and cotton seed. Eight of these 24 (33.3%) had positive tests, and 5 of the 8 had elevated serum immunoglobulin E (IgE) levels. Only one of the 8 skin-test-positive workers had symptoms of byssinosis. Only 1 of 30 control workers' skin tested with cotton extract reacted, and none had an increased serum IgE level (P < 0.01). Both baseline lung function and across-shift changes did not differ between workers with positive and negative skin test reactions or between workers with normal and elevated IgE levels. Additionally, we studied the response in vitro of nonsensitized guinea pig trachea to cotton bract extract and demonstrated a dose-dependent contractile response. These data suggest that while immunological findings are frequent in textile workers, they correlate poorly with respiratory symptoms and function and may not be the basis for the airway obstruction seen in this disease.Supported in part by grant no. YF 733 from the National Institutes of Health, Bethesda, Maryland, USA, grant no. R01 OHO 2593-01A1 from the National Institute of Occupational Safety and Health, Centers for Disease Control, Atlanta, Georgia, USA, and the Henry and Catherine Gaissman Fund, New York, NY, USA