Respiratory symptoms and cotton dust exposure; results of a 15 year follow up observation

Assessment of pulmonary function and respiratory symptoms among INDIAN textile sizing mill workers

BACKGROUND

Textile-sizing mill workers are exposed to various hazards in the sizing units during their working hours and are at risk of acquiring lung impairments due to the usage of sizing chemicals in the sizing process.

OBJECTIVE

The main aim of this study is to assess the influence of cotton dust and sizing agents on lung function and breathing difficulties among Indian textile sizing mill workers.

METHODS

This cross-sectional study was carried out at a textile-sizing mill from August 2022 to September 2022. A modified questionnaire based American Thoracic Society's standard was used to assess respiratory symptoms among sizing mill workers and the pulmonary function test was conducted Spirometry. The chi-square test was used to find the difference between respiratory symptoms and the t-test was used to find the difference between spirometric parameters.

RESULTS

Textile sizing mill workers showed significant (P <  0.0001) decline in peak expiratory flow rate, forced vital capacity (FVC), ratio of FEV1 and forced vital capacity, and forced expiratory volume in 1 s (FEV1). There was an association between symptoms and duration of exposure to pulmonary abnormality. Sizing mill workers showed a significant decline in lung functions and an increase in pulmonary symptoms. As the service duration of exposure in terms of years increased, respiratory symptoms increased and spirometric abnormality also increased.

CONCLUSION

This study confirms that sizing agents such as polyvinyl alcohol (PVA), emulsifier, wax, carboxymethyl cellulose (CMC), and starch used in sizing mills are also responsible for respiratory illness and lung impairment among textile workers.

Assessing the Feasibility of a Multifaceted Intervention Package for Improving Respiratory Health of Textile Workers: Findings From the MultiTex Pilot Study in Karachi, Pakistan

We piloted the development and implementation of a multifaceted intervention package for improving respiratory health among textile workers using a pre-post design at six mills in Karachi. The intervention, implemented following a baseline survey (n = 498), included health and safety training of workers and managers, promotion of cotton dust control measures, and the provision of facemasks. Follow-up surveys were conducted at 1, 6, and 12 months post-intervention. Knowledge, attitude, and practice (KAP) scores and respiratory symptoms were assessed through a questionnaire and spirometry was conducted. The intervention was provided to 230 workers and led to an improvement in KAP scores that was more likely among workers with a higher educational status, spinners, smokers, those with a permanent employment status, working in morning shifts, and with ⩾5 years of textile experience. We found the intervention acceptable and feasible in these textile mills henceforth, trials are required to determine its effectiveness.

The health and economic burden of dust pollution in the textile industry of Faisalabad, Pakistan

BACKGROUND

Exposure to dust in textile mills adversely affects workers' health. We collected epidemiological data on textile workers suffering from respiratory diseases and assessed work absence associated with illnesses in Faisalabad, Pakistan.

METHODS

We recruited 206 workers using multistage sampling from 11 spinning mills in Faisalabad, Pakistan. The data were collected using 2-week health diaries and face-to-face interviews. The data pertains to socio-demographics, occupational exposures, the state of the workers' health, and other attributes. A theoretical framework of the health production function was used to estimate the relationship between cotton dust exposure and respiratory illnesses. We also estimated functional limitations (e.g., work absence) associated with dust exposure. STATA 12 was used to calculate descriptive statistics, an ordered probit for byssinosis, a probit model for chronic cough, and three complementary log-log models for blood phlegm, bronchitis, and asthma to measure dose-response functions. A Tobit model was used to measure the sickness absence function.

RESULTS

We found that cotton dust exposure causes a significant health burden to workers, such as cough (35%), bronchitis (17%), and different grades of byssinosis symptoms (22%). The regression analysis showed that smoking cigarettes and working in dusty sections were the main determinants of respiratory diseases. Dusty work sections also cause illness-related work absences. However, the probability of work absence decreases with the increased use of face masks.

CONCLUSION

The study's findings imply the significance of promoting occupational safety and health culture through training and awareness among workers or implementing the use of safety gadgets. Promulgating appropriate dust standards in textile mills is also a need of the hour.

Prevalence of chronic respiratory symptoms and associated factors among woodwork workers in Bahir Dar City, Ethiopia; a comparative cross-sectional study

BACKGROUND

Exposure to wood dust can cause respiratory symptoms, like cough, phlegm, breathlessness, and chest pain, reduce lung function.

OBJECTIVE

The objective of the study was to assess the prevalence of respiratory symptoms and associated factors among woodwork workers in Bahir-Dar city, Ethiopia.

METHODS

A comparative cross-sectional study was employed among 229 exposed and 228 unexposed groups. Participants for the study were selected using simple random sampling technique. The chronic respiratory symptoms were assessed using a questionnaire adopted from the American Thoracic Society. The data was entered using Epi-Data version 4.6 and export to SPSS version 22 for analysis. Poisson regression, Multivariate linear regression and multivariable logistic regression analysis were used to identify factors associated with woodworkers, general population and in pooled analysis.

RESULT

The prevalence of having at least one chronic respiratory symptom was higher among exposed group (59.4%) than unexposed group (18.0%) with PR = 3.03(95%CI: 2.45, 4.45). In woodworker; Not taking health and safety training(5.15,95%(CI:1.93-13.76),primary educational(3.85,95%,CI:(1.1,13.47), not using Mask(6.38, 95%CI:(2.69-15.76) & number of families(3.05,95%,CI:1.04-9.028), In general population; Number of family members(2.75, 95%CI:1.1-7.19)& lower monthly income (3.3, 95%CI: (1.49-7.4), and In pooled analysis; wood dust exposure status 14.36 95%, CI:(7.6-27.00),primary education(2.93,95%CI:1.24-6.92), number of families(3.46,95%CI:1.8-6.64), lower monthly income(2.13,95%CI:1.19-3.81), & smoking (6.65, 95%CI:1.19-36.9) were associated with respiratory symptom.

CONCLUSION

Prevalence of respiratory symptoms was higher among exposed group than unexposed group. Reduced wood dust exposure status, Provision of occupational safety and health training, use of respiratory protective devices is recommended to reduce respiratory symptoms among woodwork workers.

Respiratory symptoms and pulmonary function impairment among textile industry workers in Alexandria, Egypt

Occupational exposure to cotton dust is still an important cause of respiratory problems in textile workers particularly in less developed countries like Egypt. Evaluate respiratory symptoms and diseases, and pulmonary function pattern among Egyptian textile workers. Cross sectional comparative study was conducted from December 2019 to September 2020 in a textile factory in Egypt; 364 male workers (184 cotton dust exposed workers, and 180 unexposed workers) were included. Participants were subjected to an interviewing questionnaire, British Medical Research Council questionnaire, anthropometric measurements, pulmonary function tests, and byssinosis grading format. Descriptive and analytic statistics were conducted. Chronic cough, phlegm production, and shortness of breath grade I, II and III were more reported in cotton dust exposed workers than unexposed workers (P#x003C;0.01, P#x003C;0.01, and P=0.02, respectively). Prevalence of chronic bronchitis was significantly higher among cotton dust exposed workers (12%) than unexposed workers (3.9%) (P#x003C;0.01). The mean percent predicted values of lung function indices reflecting large-1irway function (VC, FVC, FEV1, FEV1%, PEFR, and FEF75) were significantly lower in cotton dust exposed workers (P#x003C;0.01). Prevalence of byssinosis was 22.8%. Workers with byssinosis had significantly higher prevalence of respiratory symptoms, chronic bronchitis, cross-shift reduction in PEFR and significant decrease in mean percent predicted values of FVC, FEV1, PEFR, FEF75, and FEF50 than workers without byssinosis. This study revealed a substantial association between cotton dust exposure at work and respiratory symptoms and morbidity. Regular measurement of cross shift change in PEFR is recommended among exposed workers for early diagnosis of byssinosis.

Health risk assessment of indoor air quality, sociodemographic and kitchen characteristics on respiratory health among women responsible for cooking in urban settings of Oromia region, Ethiopia: a community-based cross-sectional study

OBJECTIVES

In Ethiopia, where biomass fuel is used by the majority of the population, women who are primarily responsible for cooking are at a higher risk of having respiratory symptoms. However, there is limited information on the respiratory symptoms of exposed women. This study assessed the magnitude of respiratory disease symptoms and associated factors among women responsible for cooking in Mattu and Bedele towns, south-west Ethiopia.

METHODS

A community-based cross-sectional study was conducted among 420 randomly selected women in urban settings in south-west Ethiopia. Data were collected through face-to-face interviews using a modified version of the American Thoracic Society Respiratory Questionnaire. The data were cleaned, coded and entered into EpiData V.3.1 and exported into SPSS V.22 for analysis. Bivariable and multivariable logistic regression analyses were used to identify factors associated with respiratory symptoms at a value of p<0.05.

RESULTS

It is found that 34.9% of the study participants have respiratory symptoms (95% CI 30.6% to 39.4%). Unimproved floor (adjusted OR (AOR)=2.4 at 95% CI 1.42 to 4.15), presence of thick black soot in the ceiling (AOR=2.1 at 95% CI 1.2 to 3.6), using fuel wood (AOR=2.3 at 95% CI 1.1 to 4.7), using a traditional stove (AOR=3.37 at 95% CI 1.85 to 6.16), long duration of cooking (AOR=2.52 at 95% CI 1.4 to 4.5) and cooking room without a window (AOR=2.4 at 95% CI 1.5 to 3.9) were significantly associated with women's respiratory symptoms.

CONCLUSION

More than two in six women who cook had respiratory symptoms. Floor, fuel and stove type, soot deposits in the ceiling, duration of cooking and cooking in a room without a window were the identified factors. Appropriate ventilation, improved floor and stove design and the switch to high-efficiency, low-emission fuels could help to lessen the effects of wood smoke on women's respiratory health.

Prevalence of Respiratory Symptoms and Risk Factors Among Street Sweepers in Gondar City Northwest, Ethiopia, 2021: A Cross-Sectional Study

BACKGROUND

Street sweepers are exposed to a variety of risk factors such as dust, bioaerosols, and volatile organic matter, which are responsible for the development of various respiratory symptoms and lung function impairments. However, there is a limited data on the prevalence of respiratory symptoms and associated factors among street sweepers in Ethiopia, especially in the study area.

OBJECTIVE

This study aimed to assess the prevalence of respiratory symptoms and associated factors among street sweepers in Gondar town, northwest Ethiopia, in 2021.

METHODS

Using simple random sampling technique, a total of 391 workers were selected between August 10 and September 15, 2021. The data was entered and analyzed using the Epi Info Version 7 and Statistical Package for Social Science (SPSS) 22 software, respectively. Descriptive statistics, bivariable, and multivariable logistic regression model were used. P ⩽ .05 and adjusted odds ratios (AOR) with 95% confidence interval (CI) were used to declare the statistical significance.

RESULT

A total of 391 respondents, with a response rate of 99.2% participated. The prevalence of respiratory symptoms among street sweepers was 35.3% (95% CI: 30.2, 40.5). History of respiratory illness (AOR = 7.75, (95% CI: 3.45, 17.45), washing personal protective equipments (PPE) after use (AOR = 4.77; 95% CI: 2.02, 11.28), previous work in cement (AOR = 3.10, 95% CI: 1.32, 7.34), and flour factories (AOR = 2.13, 95% CI: 2.02, 4.43), and alcohol drinking (AOR = 3.77, 95% CI: 1.94, 7.29) were associated with respiratory symptom among street sweepers.

CONCLUSION

The overall prevalence of respiratory symptoms among street sweepers was 35.3%. Previous respiratory illness, washing personal protective equipment after use, previous work in a cement and flour factory, and drinking alcohol were independently associated with respiratory symptoms. To reduce the respiratory symptoms among street sweeper, it is advisable implementing safe work practice measures and behavioral changes among workers.

From properties to toxicity: Comparing microplastics to other airborne microparticles

Microplastic (MP) debris is considered as a potentially hazardous material. It is omnipresent in our environment, and evidence that MP is also abundant in the atmosphere is increasing. Consequently, the inhalation of these particles is a significant exposure route to humans. Concerns about potential effects of airborne MP on human health are rising. However, currently, there are not enough studies on the putative toxicity of airborne MP to adequately assess its impact on human health. Therefore, we examined potential drivers of airborne MP toxicity. Physicochemical properties like size, shape, ζ-potential, adsorbed molecules and pathogens, and the MP's bio-persistence have been proposed as possible drivers of MP toxicity. Since their role in MP toxicity is largely unknown, we reviewed the literature on toxicologically well-studied non-plastic airborne microparticles (asbestos, silica, soot, wood, cotton, hay). We aimed to link the observed health effects and toxicology of these microparticles to the abovementioned properties. By comparing this information with studies on the effects of airborne MP, we analyzed possible mechanisms of airborne MP toxicity. Thus, we provide a basis for a mechanistic understanding of airborne MP toxicity. This may enable the assessment of risks associated with airborne MP pollution, facilitating effective policymaking and product design.

Effect of cotton dust on lungs among female workers in cotton industry in northern Gujarat, India

Byssinosis is a disabling occupational lung disease caused by cotton dust. It is a well-known occupational respiratory disease in cotton industry workers caused by cotton dust pollution. Many studies have been documented the effects of cotton dust on pulmonary function among workers employed in cotton-spinning mills. However, little data exist on the prevalence of this disorder in female workers particularly in western part of India. The present study was conducted to analyze the effects of exposure to cotton dust on pulmonary functions among female workers. The study was designed to assess the effects of exposure to cotton dust on lung functions among female cotton industry workers. Study group comprises 50 Female workers of cotton industry and control group comprises 50 age matched females who were neither worked in cotton industry nor exposed to cotton dust. Information was collected using standardized questionnaires, physical examination and spirometric measurements. Student's T test was used to find the difference between spirometric parameters. All the respiratory parameters (FVC, FEV1, FEV1/FVC ratio, FEF 25-75 % PEFR and MVV) were reduced in cotton industry workers as compared with control subjects (p<0.0001) and no significant difference of SpO2 between groups. Cotton dust exposure makes huge impact on respiratory parameters of the cotton industry workers. This deterioration in respiratory health deteriorates with increasing duration of exposure. The health hazards caused by cotton dust should be controlled by creating awareness among the workers & employers.

Contemporary Prevalence of Byssinosis in Low- and Middle-Income Countries: A Systematic Review

We aimed to identify the contemporary prevalence of byssinosis through a systematic review. We used Medline, Web of Science, Embase, and Global Health databases to identify studies published in any language between 2000 and 2019, reporting primary data on byssinosis among adults. We used the Joanna Briggs Institute checklist to estimate the risk of bias in studies and undertook a qualitative, narrative data analysis. The review considered the prevalence of byssinosis, chest tightness, and airflow obstruction in textile workers in low- and middle-income countries (LMICs). We found 26 relevant studies that included 6930 workers across 12 countries. Most of the studies (n = 19) were from Asia, and 7 from African countries. Twenty-five studies were cross-sectional surveys while 1 was a cohort study. The prevalence of byssinosis was reported by 18 studies, and ranged from 8% to 38%, without any clear associations, at the group level, between the prevalence of byssinosis and durations of workers’ exposures. Prevalence of chest tightness ranged between 4% and 58% and that of airflow obstruction between 10% and 30%. We found a strong correlation ( r = 0.72) between prevalence of byssinosis and cotton dust levels. Our findings indicate that byssinosis remains a significant, contemporary problem in some parts of the textile sector in LMICs.

Prevalence and Factors Associated with Respiratory Symptoms Among Bahir Dar Textile Industry Workers, Amhara Region, Ethiopia

INTRODUCTION

The expansions of labor-intensive investments in a developing countries, especially in textile production create a dusty work environment for workers, and those workers are from the low socio-economic group and need special safety concern.

OBJECTIVE

This study was aimed at assessing the prevalence of respiratory symptoms and associated factors among textile factories workers in Bahir Dar, Amhara region, Ethiopia, 2015.

METHODS

Institutional based cross-sectional study design was employed among randomly selected 384 textile workers using pre-tested interviewer-administered questionnaire. We stratified workers by their working section in the textile industries. Then the proportional numbers of workers were selected from each working section of the factory by using a random number generator. The identification number of workers from each factory was used for selection. The data were checked, coded, and entered to Epi-info Version 7 and exported to the Statistical Package for Social Science Version 20 for further analysis. Both bivariate and multivariate logistic regressions were used to identify associated factors. Variables having a P ⩽ .2 were fitted to multivariate logistic regression so as to assess the presence and strength of association with the respiratory symptom. Variables having a P < .05 were considered as significant.

RESULTS

Three hundred eighty-three (99.74%) of the study participants responded completely filling the questionnaire. In this study, the prevalence of cough, phlegm, bronchitis, chronic bronchitis, and chest pain among the respondents were 31 (8.1%), 45 (11.7%), 26 (6.8%), 2 (0.5%), and 21 (5.5%), respectively. Generally, 141 (36.81%) of the respondents have either of the above respiratory symptoms in the textile industry. Working in the spinning section (AOR = 3.26, 95% CI: 1.80, 5.89), being in the grade 11 and 12 level and below (AOR = 2.36, 95% CI: 1.50, 3.70) and personal protective equipment (PPE) utilization (AOR = 4.88 95% CI: 1.54-15.45) were significantly associated with respiratory symptoms in the multivariate analysis.

CONCLUSION

The prevalence of respiratory symptoms in Bahir Dar Textile workers was relatively high. Working department, educational status, and PPE use were variables significantly associated with respiratory symptoms in this study. Experience sharing across departments, employing educated workers and provision of personal protective equipment are important tasks to be followed to reduce respiratory symptoms in the industry.

Chronic Cough Due to Stable Chronic Bronchitis: CHEST Expert Panel Report

BACKGROUND

Chronic cough due to chronic bronchitis (CB) causes significant impairment in quality of life, and effective treatment strategies are needed. We conducted a systematic review on the management of chronic cough due to CB to update the recommendations and suggestions of the American College of Chest Physicians (CHEST) 2006 guideline on this topic.

METHODS

This systematic review asked three questions: (1) What are the clinical features of the history that suggest a patient's cough-phlegm syndrome is due to CB? (2) Can treatment of stable CB improve or eliminate chronic cough? (3) Can therapy that targets chronic cough due to CB prevent or reduce the occurrence of acute CB exacerbations? Studies of adult patients with CB were included and assessed for relevance and quality. Based on the systematic review, guideline suggestions were developed and voted on by using the CHEST organization methodology.

RESULTS

The search strategy used an assortment of descriptors and assessments to identify studies of chronic cough due to CB.

CONCLUSIONS

The evidence supporting the management of chronic cough due to CB is limited overall and of low quality. This article provides guidance on treatment by presenting suggestions based on the best currently available evidence and identifies gaps in our knowledge and areas for future research.

Correlates of Self-Reported Cotton Fever Experience among People Who Inject Opioids

Background: Cotton fever is a febrile syndrome occurring after intravenous drug injection. Although its clinical presentation is well described in the literature, data regarding prevention is lacking. We aimed to assess proportion and correlates of cotton fever experience among people who inject opioids. Methods: We performed a cross-sectional study using data from the community-based survey PrebupIV conducted in France in 2015 among 557 people who regularly injected opioids. Self-reported sociodemographic data, together with data on substance use, injecting practices and occurrence of cotton fever were all collected through face-to-face (n = 398) or online (n = 159) questionnaires. Factors associated with cotton fever experience were assessed using logistic regression model. Results: Over half of the participants (54%) reported cotton fever experience. In the multivariable logistic regression, crack cocaine injection (adjusted Odds Ratio (aOR) = 1.96, 95% Confidence Interval (CI) = 1.03-3.63), longer duration of opioid use (for 1 year of use: aOR = 1.05, 95%CI = 1.02-1.09), and filtering mainly with cotton filters (compared with membrane filters, aOR = 1.86, 95%CI = 1.24-2.78) were all associated with cotton fever experience. Conclusions: Our findings highlight that cotton fever is a frequent complication of injecting drug use. Avoiding the use and reuse of cotton balls to filter injected solutions, and promoting membrane filters use could reduce the risk of the condition occurring.

Fractional exhaled nitric oxide and respiratory complaints in Hajj pilgrims wearing a cotton towel or plain cotton ihram

Objective

Hajj is an important component of Islam. This study aimed to determine the effect of wearing a cotton towel or plain cotton ihram on the onset of respiratory symptoms and fractional exhaled nitric oxide (FeNO) levels in Hajj pilgrims.

Methods

One hundred male nonsmoking subjects (age: 20–60 years) without a previous clinical history of respiratory illnesses were included. Fifty subjects were dressed in a cotton towel ihram and 50 wore a plain cotton ihram (control group). Respiratory symptoms and FeNO levels were recorded on the day before leaving for Hajj, when ihrams were removed, and when the pilgrims had returned home.

Results

Pilgrims who wore cotton towel ihrams showed significantly higher rates of respiratory symptoms, including being generally ill, coughing, a sore throat, and a runny nose, than those who wore plain ihrams. FeNO levels also tended to be higher in pilgrims who wore a cotton towel ihram compared with those with a plain cotton ihram during and after Hajj.

Conclusions

Hajj pilgrims who wear cotton towel ihrams may have a risk of respiratory symptoms, including a cough, sore throat, and runny nose. Therefore, a plain cotton ihram is advisable while performing Hajj to minimize respiratory illness.

Occupational Exposure to Endotoxin along a Municipal Scale Fecal Sludge Collection and Resource Recovery Process in Kigali, Rwanda

Background: Little is known about occupational exposures that occur along fecal sludge collection and resource recovery processes. This study characterizes inhaled endotoxin exposure to workers of a municipal scale fecal sludge-to-fuel processes in Kigali, Rwanda. Methods: Forty-two task-based air samples were collected from workers in five tasks along the fecal sludge collection and resource recovery process. Samples were processed for endotoxin using the limulus amebocyte lysate (LAL) test. To account for exposure variability and compare measured concentrations to established exposure limits, we used Monte Carlo modeling methods to construct distributions representing full eight-hour (8-h) exposures to endotoxin across eight exposure scenarios. Results: Geometric mean (GM) endotoxin concentrations in task-based samples ranged from 11–3700 EU/m³ with exposure concentrations increasing as the dryness of the fecal sludge increased through processing. The thermal dryer task had the highest endotoxin concentrations (GM = 3700 EU/m³) and the inlet task had the lowest (GM = 11 EU/m³). The geometric means (GM) of modeled 8-h exposure concentrations were between 6.7–960 EU/m³ and highest for scenarios which included the thermal dryer task in the exposure scenario. Conclusions: Our data suggest the importance of including worker exposure considerations in the design of nascent fecal sludge management processes. The methods used in this study combine workplace sampling with stochastic modeling and are useful for exposure assessment in resource constrained contexts.

Byssinosis and tuberculosis amongst "home-based" powerloom workers in Madhya Pradesh State, India

BACKGROUND

Byssinosis is an occupational lung disease observed among workers exposed to cotton, flax, and hemp dust. The severity and extent of Byssinosis are well recognised in the high-income countries and control measures have been implemented to prevent the disease. In India, there are conflicting evidence on burden estimation of the disease, followed by inadequate prevention and control of Byssinosis.

DESIGN/METHODS

We did a cross-sectional study to assess the prevalence of Byssinosis in "home-based" power-loom workers in Mominpura, an administrative ward of Burhanpur Municipality with 2800 population in the state of Madhya Pradesh, India. 290 adults working from "home-based" power loom units were randomly selected, profiled and screened for Byssinosis like symptoms with the help of a semi-structured questionnaire and simple hand-held peak expiratory flow monitor. For epidemiological purposes the symptoms were classified based on Schilling's classification. Chest x-rays were done for selected subjects. Sputum smear microscopy for detecting TB was done for those who had Byssinosis like symptoms.

RESULTS

Prevalence of Byssinosis among "home based" powerloom workers was found to be 98% [n = 283, 95 CI (95.65-98.96)]. Peak expiratory flow rate (PEFR) was reduced in 44% (n = 124), of which 81 (29%) had more than 50% PEFR reduction, and of these, 69 (29%) were in early stage of Byssinosis (Grade 0.5). 11% of study participants who had Byssinosis like symptoms, also had TB.

CONCLUSIONS

Byssinosis is highly prevalent in "home-based" power loom units in Madhya Pradesh. Adequate advocacy on awareness and prevention; prompt diagnosis and linkages to treatment services in "home-based" power loom units are urgently required to address Byssinosis at an early disease stage.

Respiratory Symptoms and Lung Function among Greek Cotton Industry Workers: A Cross-Sectional Study

Background:

Workers in cotton industry are occupationally exposed to various dust-related hazards. The nature of these agents and the respective exposure levels depend on the cotton industry specific sector. These exposures could be associated with respiratory symptoms and changes in lung function parameters.

Objective:

To evaluate associations between occupational exposure and respiratory function as well as reported symptoms in several groups of workers at different stages of the cotton industry in a vertical approach that covers all the major sectors—from cotton ginning to weaving and fabric production.

Methods:

A questionnaire on respiratory symptoms and individual as well as workplace characteristics was completed by 256 workers at the cotton industry and 148 office workers (control group). Both groups underwent spirometry.

Results:

Workers in cotton industry reported a higher prevalence of severe dyspnea (p=0.002) and wheezing (p=0.004) compared to the control group. Also they were found to have a lower predicted FEV1% (p<0.029) and lower FEV1/FVC (p<0.001) values. In addition, a higher prevalence of FEV1% <80% (p<0.001) and FEV1/FVC <70% (p=0.041) were found among textile workers. Similar results were found for non-smoker textile workers compared to non-smoker control group workers. Those working in cotton ginning mills recorded the highest decrease of spirometric values. Duration of employment in cotton industry and smoking use were found to be predictors of lung function decline for cotton industry workers.

Conclusion:

Occupational exposure to cotton dust was associated with increased prevalence of respiratory symptoms and obstructive pattern in pulmonary function test.

Cotton dust exposure: Analysis of pulmonary function and respiratory symptoms

Background:

Cotton industry workers are exposed to various hazards in the different departments of textile factories. The major health problems associated with cotton dust are respiratory problems, byssinosis, bronchitis and asthma.

Objective:

To study the effect of cotton dust exposure on pulmonary function and respiratory symptoms.

Settings and Design:

This cross-sectional observational study was conducted at cotton mill in the Ahmedabad city.

Materials and Methods:

One hundred cotton mill workers of the weaving and spinning area participated in this study while 100 age- and gender-matched male subjects living in the residential area served as the control group. A questionnaire was used to inquire about respiratory symptoms and spirometry was done in both the groups.

Statistical Analysis Used:

Student's t-test was used to find the difference between spirometric parameters, and Chi-square test was used to find the difference between respiratory symptoms.

Results:

Respiratory symptoms were statistically significantly more common in the cotton mill workers compared to control group. Cotton mill workers group also showed significant (P < 0.0001) decrease in forced expiratory volume in 1 s (FEV1), ratio of FEV1 and forced vital capacity (FVC) and peak expiratory flow rate, and no significant difference of FVC between groups. There was an association of duration of exposure and symptoms with spirometric abnormality.

Conclusion:

Cotton mill workers showed a significant decrease in spirometric parameters and increase in respiratory symptoms. As the duration of exposure and symptoms increased, spirometric abnormality increased.

Respiratory problems among cotton textile workers

Background:

Long term occupational exposure to cotton dust is associated with respiratory symptoms and loss of pulmonary function.

Aim:

This study was conducted to explore respiratory symptoms, pulmonary function tests and chest radiography of workers, and to evaluate the findings of high resolution computed tomographyand its correlation with pulmonary function tests (PFT).

Material and Methods:

The study was conducted on 100 cotton workers as exposed group and 100 unexposed subjects. Smokers were excluded from the study. All workers were interviewed and examined by the pulmonologist. PFT and chest radiography were conducted for all subjects. HRCT was performed for those with abnormal PFT or chest radiography.

Results:

A total of 51% and 31% of the cotton textile workers had one or more respiratory symptoms and respiratory signs respectively. 28% of subjects in the exposed group and 5% of subjects in unexposed group had obstructive pattern. Bronchia wall thickening and air trapping were the most frequent chest radiography and HRCT abnormalities respectively. There was a significant correlation between HRCT and the results of PFT.

Conclusion:

We conclude that long term exposure to cotton dust is associated with obstructive disease that increase with duration of exposure (history of working years), also use of HRCT as a sensitive tool in the assessment of pathologic changes and it's correlation with PFT, confirms the expected pathophysiology of airway obstruction in cotton workers.

Pulmonary effects of intermittent, seasonal exposure to high concentrations of cotton dust

AIM: To quantify the exposure levels and to assess pulmonary reactions associated with exposure to cotton dust and its biological contaminants.

METHODS: All employees (51 male workers) of a ginning industry as well as 51 referent unexposed subjects from clerical staff of an educational center were investigated. Atmospheric concentrations of cotton dust and bioaerosols were measured. Furthermore, bacterial and fungal genera and species were identified by an expert microbiologist and an experienced mycologist. A standard respiratory symptom questionnaire was filled out for the subjects and they underwent multiple spirometry tests, at the beginning and at the end of work season as well as prior to (pre-exposure base line values) and at end of the first shift of workweek (post exposure).

RESULTS: Gram negative bacteria including Enterobacter agglomerans and Pseudomonas spp. were found to be the dominant bacterial species and genera, respectively. Similarly, dominant fungi were identified to be Mucor sp. Rhizopus sp. and Aspergillus niger. Mean atmospheric concentrations of cotton dust in ginning and outdoor areas were found to be 35.2 and 6.8 mg/m³, respectively. The prevalence rates of cough, phlegm, wheezing, dyspenea and grade 1/2 byssinosis among the exposed subjects were significantly higher than their corresponding values for the unexposed employees (P < 0.05). Additionally, significant differences were noted in the mean baseline value (preshift) of vital capacity, forced expiratory volume in the first second (FEV1) and FEV1/forced vital capacity ratio of the exposed subjects when compared with those of their referent counterparts. Similarly, significant cross shift decrements were noted in most parameters of pulmonary function of the exposed subjects.

CONCLUSION: Seasonal exposure to cotton dust induces both acute, partially reversible, and chronic irreversible decrements in the lungs’ functional capacities as well as increased prevalence of respiratory symptoms.

A study of respiratory function among the workers engaged in ginning processes

Background:

Known respiratory health effects of exposure to cotton dust are mainly altered pulmonary function findings and symptom of chest tightness. A number of studies have been carried out all over the world to enumerate and evaluate the health effects of cotton dust exposed workers in different processes. However, such studies carried out in ginning industry especially in Indian context are scanty.

Objectives:

This study was initiated to explore occupational and morbidity details and respiratory functional status of the exposed workers as well as to investigate across the working shift pulmonary function changes.

Materials and Methods:

A cross-sectional study was conducted including workers from ginning units where principal exposure is from cotton dust. All the workers of the selected ginning units were subjected to an interview with a predesigned questionnaire to collect occupational and medical history, clinical examination and pulmonary function test.

Results:

In this present study, no cross-shift significant change in relation to PEFR and FEV₁ values is observed. However, chronic effect on lung function is observed in a few subjects and declining trend of values was observed with increasing job duration as well as age of workers and among smokers. Other health problems among these subjects were backache and joint pain.

Conclusions:

Studies on cotton textile workers have shown both cross-shift and chronic decline of values. In this study on ginning workers, chronic effect only is observed. This difference of observation may be explained by different nature of exposure in case of ginning. This study recommends regular periodic clinical examination, lung function test and monitoring of dust, gram-negative bacteria and endotoxins in such workplaces.

Dust, endotoxin, fungi, and bacteria exposure as determined by work task, season, and type of plant in a flower greenhouse

BACKGROUND

Greenhouse workers are exposed to dust, endotoxin, fungi, and bacteria potentially causing airway inflammation as well as systemic symptoms. Knowledge about determinants of exposure is a prerequisite for efficient prevention through knowledge-based reduction in exposure. The objective of this study was to assess the occupational exposure in a flower greenhouse and to investigate the impact of work tasks on the intensity and variability in exposure.

METHODS

Seventy-six personal full-shift exposure measurements were performed on 38 employees in a Danish flower greenhouse producing Campanula, Lavandula, Rhipsalideae, and Helleborus. The samples were gravimetrically analysed for inhalable dust. Endotoxin was assessed by the Limulus Amoebocyte Lysate test and culture-based quantification of bacteria and fungi was performed. Information on the performed tasks during sampling was extracted from the greenhouse electronic task logging system. Associations between log-transformed exposure outcomes, season, and work tasks were examined in linear mixed-effects regression with worker identity as random effect.

RESULTS

Measured concentrations ranged between 0.04 and 2.41mg m(-3) for inhalable dust and between 0.84 and 1097 EU m(-3) for endotoxin exposure, with the highest mean levels measured during Lavandula and Campanula handling, respectively. Personal exposure to fungi ranged between 1.8×10(2) and 3.4×10(6) colony-forming units (CFU) m(-3) and to bacteria between 1.6×10(1) and 4.2×10(5) CFU m(-3). Exposure to dust, endotoxin, fungi, and bacteria differed between seasons. Packing Lavandula, sticking, potting, and grading Rhipsalideae, and all examined tasks related to Campanula production except sticking increased dust exposure. Endotoxin exposure was increased during sticking Campanula and pinching or packing Rhipsalideae, and fungi exposure was elevated by subtasks performed in the research and development area for Campanula, and by potting, packing/dumping Campanula. Sticking and working with subtasks in the research and development area for Campanula increased bacteria exposure.

CONCLUSION

This study revealed moderate dust exposure levels compared to the levels observed in other greenhouse productions and other occupations with organic dust exposure such as farming. However, high exposures to bacteria and fungi were detected during selected tasks and the proposed health-based endotoxin exposure limit of 90 EU m(-3) was exceeded in 30% of the samples, which may have health implications for the employees. Exposure levels were found to vary depending on the tasks performed, and thereby results can be used to direct task-based initiatives to reduce workplace exposures.

Prevalence and risk factors of respiratory symptoms among home-based garment workers in Bangkok, Thailand

This study aimed to determine the prevalence and risk factors associated with respiratory symptoms. A cross-sectional study with random sampling method was employed and 300 home-based garment workers (HBGWs) were recruited. Risk factors, including personal factors; knowledge, health preventive behaviors, and skill of self-health surveillance, working condition, and respiratory symptoms were assessed. Data were collected using self-reported questionnaires. Prevalence of respiratory symptom was 22.3%. Majority of participants were female (78%). Mean age and working experience were 37.38 years (SD = 10.70) and 13.58 years (SD = 8.71), respectively. Allergic respiratory symptoms (odds ratio [OR] = 16.5; 95% confidence interval [CI] = 8.61-31.7) and garment dust exposure (OR = 12.3; 95% CI = 6.49-23.3) were significantly associated with respiratory symptoms (P < .001). Logistic regression analysis indicated history of allergic predicted the respiratory symptoms (OR = 12.96; 95% CI = 4.24-39.55). HBGWs who had serious allergic symptoms and high exposure to dust were at risk of respiratory symptoms. Therefore, preventive program for garment dust exposure among HBGWs is needed.

Prevalence of respiratory symptoms and disorders among rice mill workers in India

OBJECTIVES

Lung function tests have become an integral part of assessment of pulmonary disease. Diseases of the respiratory system induced by occupational dusts are influenced by the duration of exposure. The aim of the study is to investigate the impairment of lung function and prevalence of respiratory symptoms among the rice mill workers.

METHODS

A total of 120 rice mill workers from three districts of Karnataka were included in this study. Fifty urban dwellers from the same socio-economic level were selected as controls. The study included clinical examination, assessment of respiratory symptoms, pulmonary function test, measurement of peak expiratory flow rate, absolute eosinophil count, ESR estimation, total IgE estimation and radiographic test.

RESULTS

The present study has shown that the rice mill workers complained of several types of respiratory disorders like phlegm (40.8 %), dyspnea (44.2 %), chest tightness (26.7 %), cough (21.7 %), and nose irritation (27.5 %). Rice mill workers exposed to dust presented significantly (p < 0.05) lower levels of FVC (3.44 ± 0.11), FEV1 (2.73 ± 0.15) and PEFR (304.95 ± 28.79) than the controls. The rice mill workers are having significantly higher absolute eosinophil counts, total IgE and ESR than control groups. The hematological findings suggest that the harmful effects may be linked to both non-specific irritation and allergic responses to rice husk dust among rice mill workers.

CONCLUSION

Dust exposure in the working environment affects the lung function values and increased the respiratory symptoms among the rice mill workers.

Longitudinal pulmonary functional loss in cotton textile workers: a 5-year follow-up study

BACKGROUND

Occupational exposure to cotton dust causes several diseases affecting the lungs, but only limited information is available on effects of long-term exposure. In this study, we aimed to evaluate longitudinal changes in selected parameters of pulmonary function in textile workers.

MATERIAL AND METHODS

This prospective cohort study began with 196 textile workers in 2006 and was completed in 2011 with 49 workers. We used standardized tests for pulmonary function on participants on the first day of the workweek in June of 2006 and 2011. Environmental samples of cotton dust were gathered with a vertical elutriator. Loss of pulmonary function was assessed based on gender and smoking status.

RESULTS

The mean number of years participants worked in the textile factory was 7.61 ± 1.83 years, and the mean age was 35.3+5.8 years. The annual FEV1 loss of all workers was 53.2 ml, giving a ratio of annual FEV1 loss to baseline FEV1 of 1.4%. Pulmonary function parameters of all participants in 2011 were significantly lower than those in 2006 (for all, p<0.05). In both surveys, pulmonary function in current smokers was lower, but this difference was not significant (p>0.05).

CONCLUSIONS

This study provides the first data on pulmonary functional loss in Turkish textile workers and supports the findings of other cohort studies that workers with long-term exposure to cotton dust may lose some pulmonary function. The ratio of annual FEV1 loss to baseline FEV1 appears to be a more accurate and comparable method than annual FEV1 loss for evaluating pulmonary functional loss.

Respiratory symptoms and illnesses among brick kiln workers: a cross sectional study from rural districts of Pakistan

BACKGROUND

Occupational risk factors are one of the major causes of respiratory illnesses and symptoms, and account for 13% of chronic obstructive pulmonary disease and 11% of asthma worldwide. Majority of brick kilns in Pakistan use wood and coal for baking the bricks which makes the brick kiln workers susceptible to high exposure of air pollution. This study was designed to describe frequency of chronic respiratory symptoms and illnesses and study the association between these symptoms and different types of work.

METHODS

This was a questionnaire based cross sectional survey conducted among the brick kiln workers in Larkana and Dadu districts, Sindh, Pakistan. A total of 340 adult men were assessed using translated version of the American Thoracic Society Division of Lung Disease (ATS-DLD) questionnaire. Logistic regression analysis was done to determine the relationship between various socio-demographic and occupational factors (age, education, type of work, number of years at work, smoking status), and the respiratory symptoms and illnesses (chronic cough, chronic phlegm, wheeze, Chronic Bronchitis and asthma).

RESULTS

Results of the study show that 22.4% workers had chronic cough while 21.2% reported chronic phlegm. 13.8% had two or more attacks of shortness of breath with wheezing. 17.1% workers were suffering from Chronic Bronchitis while 8.2% reported physician diagnosed asthma. Amongst the non-smoking workers 8.9% had Chronic Bronchitis. Multivariate analysis found that workers involved in brick baking were more likely to have Chronic Bronchitis (OR= 3.7, 95% CI 1.1-11.6, p=<0.05) and asthma (OR= 3.9, 95% CI 1.01-15.5, p=<0.05) compared to those involved in carriage and placement work.

CONCLUSION

A high frequency of respiratory symptoms and illnesses was observed among brick kiln workers. Age, nature of work and smoking were strong predictors of developing these symptoms and illnesses.

Pneumoproteins in sewage workers exposed to sewage dust

Purpose

The association between exposure to bacteria and endotoxins in sewage dust and the serum concentrations of pneumoproteins in sewage treatment plant workers were studied.

Methods

Forty-four workers from eight sewage treatment plants and 38 reference workers participated in the study. Microbial aerosol was collected by personal inhalable samplers. The concentrations of bacteria and endotoxins were determined by fluorescence microscopy and the Limulus assay, respectively. Pneumoproteins (Clara cell protein: CC16, and Surfactant proteins A and D: SP-A, SP-D) were determined by ELISA in blood samples collected post-shift.

Results

The exposure to dust ranged from 0.02 to 9.3 (geometric mean (GM) 0.3 mg/m³, of bacteria from 0.3 to 4,900 × 10³ (GM 27 × 10³) cells/m³ and endotoxins from 1 to 3,160 (GM 28) EU/m³. The exposed workers had lower CC16 [arithmetic mean (AM) 4.9 ng/ml] compared to the referents (AM 6.4 ng/ml, p < 0.01). No significant difference was observed for SP-D and SP-A. Exposure to bacteria was positively associated with CC16 (p < 0.05) and SP-D (p < 0.05), adjusting for possible confounders.

Conclusions

This study showed that exposed workers had lower serum concentration of CC16 as compared to the referents, which may reflect a long-term effect on secretion of these pneumoproteins. The positive association between exposure to bacteria and the serum concentrations of CC16 and SP-D may be explained by a transient increased permeability of the lung–blood barrier.

Ventilatory functions in cotton textile workers and the role of some inflammatory cytokines

Exposure to cotton dust in industrial environments causes inflammation in the airways of the exposed workers. This may manifest as respiratory complaints and changes in the respiratory functions after work shift and in the baseline of their ventilatory functions. The study aimed to investigate the effect of occupational exposure to cotton dust on respiratory symptoms, ventilatory functions and pro-inflammatory cytokine levels (tumor necrosis factor α, interleukin 6 and interleukin 1β). The study was conducted on 63 textile workers and 65 nonexposed subjects. Both groups were matched for age, socioeconomic status and smoking habit. The respirable dust measured in the workplace did not exceed the permissible values of the Egyptian law 1994. The bacterial counts detected were within the occupational exposure limits of the industrial settings. The results revealed that the percentage of respiratory symptoms was higher in textile workers. Respiratory complaints were chronic cough (33.2%), chronic bronchitis (39.7%) and dyspnea (23.8%) in textile workers compared to (6.2%, 6.2% and 1.5%), respectively, in controls. There was a marked reduction in the ventilatory functions (forced vital capacity and forced expiratory volume in 1 s) in the textile workers compared to the controls. The additive effect of smoking on the ventilatory functions was not apparent. The ventilatory functions of the workers were significantly positively correlated with the duration of exposure. The cytokines were insignificantly higher in the textile workers compared to their controls. The textile workers with respiratory complaints showed significant decline in ventilatory functions and elevation in the cytokine levels compared to the nonsymtomatizing workers with significant difference in interleukin 1β and interleukin 6. In conclusion, the results supported the fact that exposure to cotton dust deteriorates ventilatory functions and elevates proinflammatory cytokine levels. Analysis of the release of cytokines can be used to evaluate the immune responses to organic dust-induced airway inflammation.

Unexpected excessive chronic obstructive pulmonary disease mortality among female silk textile workers in Shanghai, China

OBJECTIVE

To investigate chronic obstructive pulmonary disease (COPD) mortality among textile workers.

METHODS

A total of 267,400 Chinese female textile employees were monitored for COPD mortality from 1989 to 2000. Textile factories in the cohort were classified into 10 industrial sectors. Age-adjusted mortality, standardized mortality ratios (SMRs) and 95% CIs were calculated by sector. In addition, RRs (HRs) adjusted for smoking and age were calculated for exposure to cotton and silk textile work compared with the other sectors in the cohort.

RESULTS

A majority of textile sectors had lower or similar COPD mortality (age-adjusted SMRs=0.58-1.15) compared with the general female population in the city of Nanjing, China. SMRs for cotton and silk workers were, respectively, 1.02 (95% CI: 0.81 to 1.28) and 2.03 (95% CI: 1.13 to 3.34). Compared with all other textile sectors in the cohort, there was greater COPD mortality among cotton workers (HR=1.40, 95% CI: 1.03 to 1.89) and silk workers (HR=2.54, 95% CI: 1.47 to 4.39).

CONCLUSION

Elevated COPD mortality among cotton workers is consistent with previous reports of adverse respiratory effects of cotton dust. The higher rate of COPD deaths among silk workers was unexpected.

Exposure to dust and endotoxin in textile processing workers

BACKGROUND

Inhalation of cotton-based particulate has been associated with respiratory symptoms and overt lung disease related to endotoxin exposure in some studies. This cross-sectional study measures personal exposure to inhalable dust and endotoxin in the textile industry of Nepal.

METHODS

This study was conducted in four sectors (garment making, carpet making, weaving, and recycling) of the textile industry in Kathmandu, Nepal. Personal exposure to inhalable dust and airborne endotoxin was measured during a full-shift for 114 workers.  

RESULTS

Personal exposure to cotton dust was generally low [geometric mean (GM) 0.81 mg m(-3)) compared to the UK workplace exposure limit (WEL) (2.5 mg m(-3)) but with nearly 18% (n = 20) of the workers sampled exceeding the limit. Exposures were lowest in the weaving and the garment sector (GM = 0.30 mg m(-3)), higher in the carpet sector (GM = 1.16 mg m(-3)), and highest in the recycling sector (GM = 3.36 mg m(-3)). Endotoxin exposures were high with the overall data (GM = 2160 EU m(-3)) being more than 20-fold higher than the Dutch health-based guidance value of 90 EU m(-3). The highest exposures were in the recycling sector (GM = 5110 EU m(-3)) and the weaving sector (GM = 2440 EU m(-3)) with lower levels in the garment sector (GM = 157 EU m(-3)). The highest endotoxin concentrations expressed as endotoxin units per milligram inhalable dust were found in the weaving sector (GM = 165 EU mg(-1)). There was a statistically significant correlation between inhalable dust concentrations and endotoxin concentrations (r = 0.37; P < 0.001) and this was particularly strong in the garment (r = 0.82; P = 0.004) and the carpet sector (r = 0.81; P < 0.001).  

CONCLUSIONS

Inhalable dust exposures measured in the weaving, carpet, and garment sectors were all below the UK WEL for cotton dust. A significant proportion of the measurements from the cotton recycling sector were above the UK WEL suggesting that better hygiene control measures are required. Airborne endotoxin concentrations in all sectors were found to exceed the Dutch health-based guidance limit of 90 EU m(-3) and may be associated with respiratory health effects.

Chronic lung function decline in cotton textile workers: roles of historical and recent exposures to endotoxin

BACKGROUND

Long-term occupational exposure to cotton dust that contains endotoxin is associated with chronic respiratory symptoms and excessive decline in forced expiratory volume in 1 sec (FEV1), but the mechanisms of endotoxin-related chronic airflow obstruction remain unclear.

OBJECTIVE

In the current study, we examined temporal aspects of the exposure-response relationship between airborne endotoxin exposure, longitudinal change in FEV1, and respiratory symptoms in a cohort of Chinese cotton textile workers.

METHODS

This prospective cohort study followed 447 cotton textile workers from 1981 to 2006. at approximately 5-year intervals. We used a generalized estimating equations approach to model FEV1 level and respiratory symptoms as a function of past exposure (cumulative exposure up to the start of the most recent 5-year survey interval) and cumulative exposure (within the most recent interval) to endotoxins, after adjusting for other covariates. Models were stratified by active versus retired work status and by years employed before the baseline survey (< 5 and > or = 5 years).

RESULTS AND CONCLUSIONS

Past exposure to endotoxin was associated with reduced FEV1 level among retired cotton workers. Among all cotton workers, past exposure was more strongly associated with reduced FEV1 for those hired < 5 years before baseline than for those who were hired > or = 5 years after baseline. Recent endotoxin exposure was significantly associated with byssinosis, chronic bronchitis, and chronic cough.

Long-term effects of work cessation on respiratory health of textile workers: a 25-year follow-up study

RATIONALE

The degree to which chronic respiratory health effects caused by exposures to cotton dust and endotoxin is reversible after cessation of textile work is unknown.

OBJECTIVES

To investigate changes in lung function and respiratory symptoms after cessation of textile work and to determine whether past exposure to cotton dust and endotoxin or smoking history modify the associations.

METHODS

We performed a prospective cohort study consisting of 447 cotton textile workers exposed to cotton dust and 472 unexposed silk textile workers, with a 25-year follow-up. Spirometry testing and respiratory questionnaires were conducted at 5-year intervals. Generalized estimated equations were used to model the average 5-year change in FEV(1) and odds ratios of respiratory symptom prevalence.

MEASUREMENTS AND MAIN RESULTS

Years since cessation of textile work was positively associated with 11.3 ml/yr and 5.6 ml/yr gains in 5-year FEV(1) change for cotton and silk workers, respectively. Among male cotton workers, smokers gained more FEV(1) per year after cessation of exposure than did nonsmokers, and the risk of symptoms of chronic bronchitis and byssinosis was larger for smoking than for nonsmoking male cotton workers.

CONCLUSIONS

Cessation of textile work was significantly associated with improvement in lung function and respiratory symptoms. The positive effect of work cessation was greater for cotton workers than for silk workers. For cotton workers, the improvement in lung function loss after cessation of textile work was greater among smokers, but no differences were observed for silk workers.

Occupation and chronic bronchitis among Chinese women

OBJECTIVE

To examine the association between occupation and chronic bronchitis among a cross section of Chinese women who participated in the Shanghai Women's Health Study.

METHODS

Cases were 4873 women who self-reported a physician-diagnosed bronchitis during adulthood. Controls were 9746 women randomly selected from Shanghai Women's Health Study participants and matched with the cases by year of birth and age at diagnosis. Lifetime occupational histories were obtained. Logistic regressions were used to evaluate the association between chronic bronchitis and occupation, adjusting for smoking, education, family income, and concurrent asthma.

RESULTS

We observed excess prevalence of bronchitis for textile occupation (odds ratio, OR = 1.09; 95% CI = 1.00-1.18) and industry (OR = 1.11; 95% CI = 1.03-1.19), welders (OR = 1.40; 95% CI = 1.01-1.92), packing and baling workers (OR = 1.39; 95% CI = 1.15-1.68), and warehousing industry (OR = 1.58; 95% CI = 1.08-2.30) We also identified several new associations that may warrant further exploration and confirmation, including employment in some metal fabrication industries, postal and telecommunication industry, and a few white-collar occupations and industries.

CONCLUSIONS

Our study indicates that the risk of chronic bronchitis among women may be increased in some occupations and industries.

Cross-shift airway responses and long-term decline in FEV1 in cotton textile workers

RATIONALE

Acute airway response, measured as cross-shift change in FEV(1), to cotton dust may lead to subsequent chronic loss of lung function in exposed workers.

OBJECTIVES

To explore the association between the magnitude and frequency of cross-shift change and chronic loss of FEV(1).

METHODS

Four hundred eight cotton workers and 417 silk workers from Shanghai textile mills were observed prospectively for 20 years, with cross-shift measurements at baseline and follow-up surveys at approximate 5-year intervals. To account for repeated measures of 5-year change, generalized estimating equations were used to estimate the relationship between the magnitude of cross-shift change in FEV(1) (DeltaFEV(1)) and subsequent 5-year annualized change. Linear regression models were used to examine the association between the number of drops in cross-shift FEV(1) (DeltaFEV(1) < 0) and annualized change over the entire study period.

MEASUREMENTS AND MAIN RESULTS

Exposure to cotton dust was associated with a 10 ml/year decrement in 5-year annualized FEV(1) decline. In addition, every 10 ml in DeltaFEV(1) drop was associated with an additional 1.5 ml/year loss in annualized FEV(1) decline. The association between the frequency of drops and annualized decline was stronger for cotton workers than for silk workers over the entire study period.

CONCLUSIONS

Cotton workers had larger and more frequent drops, as well as excessive chronic declines in FEV(1), than did silk workers. The magnitude and frequency of cross-shift drops were associated with chronic loss in FEV(1) over the entire 20-year period examined.

Documentation of the endotoxins present in the ambient air of cotton fiber textile mills in Québec

Cotton workers are recognized as being at risk of developing occupational lung diseases. Some researchers have identified endotoxins as being a potential etiologic agent for some of the respiratory problems. This study wants to document the concentration of endotoxins found in the ambient air of textile mills where cotton fibers are handled and to identify the processing steps where the highest endotoxins concentrations in the air were found and the one where the relative limit values (RLVs) are exceeded. The 4 mills studied process cotton fibers. All the air samples were analyzed using the chromogenic Limulus Amoebocytes lysate LAL method using a kinetic detection principle based on the IRSST's standard method. In this study, a large variability in the concentrations of endotoxins in the air was observed, depending on the mill, the processing step, and the time. Despite these variations, some processes can be identified as being major generators of endotoxins in the ambient air of the mills. The highest concentrations were measured in the weaving and drawing processes and reached 10,000 EU m(-3) of air. The opening, cleaning, carding, spinning and drawing processes are the other major endotoxins generating processes with concentrations from 24 to 8,700 EU m(-3) of air. The endotoxins concentrations exceeded the RLVs for 55% of the workstations in this project. This study demonstrated that endotoxins levels in the cotton industry are high and appropriate control measures are needed.

Development of a job exposure matrix (JEM) for the textile industry in Shanghai, China

We developed a job exposure matrix (JEM) for the Shanghai textile industry constructed along three axes: industry sector, textile process, and hazardous agent. We assessed 35 different categories of dust, chemical, and physical agents for 149 textile processes within nine industry sectors: cotton, cotton/synthetic, cotton/other (nonsynthetic), wool, silk, synthetic, mineral, other mixed (e.g., wool and synthetic), and nonproduction. The JEM was constructed from two components: a priori assessment of the textile process by a team of U.S. industrial hygienists, and the prevalence of exposures reported by Chinese industrial hygienists in specific textile processes within the factory. The JEM was applied to an ongoing case-cohort study of cancer in women textile workers. The JEM assessed only dichotomous exposure (ever/never), and could be coupled with cumulative exposure by years of employment. The most common exposures in cotton mills were cotton dust and solvent exposures. Dyeing processes had the highest frequency of exposures, including solvents, acids, bases and caustics, bleaching agents, dyes, dye chemicals and intermediates, and formaldehyde. Only two processes were identified with formaldehyde exposure, beck dyeing and resin finishing. The most prevalent exposures among the subcohort, occurring in more than 60% of the women, were electromagnetic fields, lubricants, and cotton dust. More than one-third of subcohort subjects were also exposed to synthetic fiber dust, and slightly less than one-third of women were exposed to endotoxin. This JEM could be applicable for epidemiologic research in other textile industries.

Endotoxin and occupational airway disease

PURPOSE OF REVIEW

This review provides an update on the role of bacterial endotoxin in occupational airway disease, a problem of importance from diagnostic and preventive points of view.

RECENT FINDINGS

Data from human inhalation studies have increased our understanding of the cell mechanisms underlying diseases related to endotoxin exposure. In addition, knowledge from molecular genetics may help us to identify individuals at risk. Several investigations have demonstrated that, apart from endotoxin, other microbial cell wall agents are also related to the risk for symptoms of occupational lung diseases, with pathogenic mechanisms different to those caused by endotoxin. Diagnostic methods have progressed from traditional lung function measurements to sampling of indicators of inflammation in the blood, nasal lavage and induced sputum. Investigations of a longitudinal design have provided important findings on the relationship between acute and chronic effects as well as exposures of risk and risk factors among individuals.

SUMMARY

Endotoxin, as well as other agents derived from microbes, are important causative agents for occupational respiratory and other diseases, and exposure may occur in a large variety of occupational environments. Recent data from longitudinal studies provide important information on diagnostic and preventive measures.

Agricultural dust exposure and respiratory symptoms among California farm operators

OBJECTIVE

To study whether dust exposure in California agriculture is a risk factor for respiratory symptoms.

METHODS

A population-based survey of 1947 California farmers collected respiratory symptoms, occupational and personal exposures. Associations between dust and respiratory symptoms were assessed by logistic regression models.

RESULTS

The prevalence of persistent wheeze was 8.6%, chronic bronchitis 3.8%, chronic cough 4.2%, and asthma 7.8%. Persistent wheeze was independently associated with dust in a dose-response fashion odds ratio, 1.2 (95% confidence interval[CI]=0.8-2.0) and 1.8 (95% CI=1.1-3.2) for low and high time in dust. A borderline significant association between chronic bronchitis and dust exposure was found. Asthma was associated with keeping livestock, but not with dust exposure.

CONCLUSIONS

Occupational dust exposure among California farmers, only one third of whom tended animals, was independently associated with chronic respiratory symptoms.

Vapor, dust, and smoke exposure in relation to adult-onset asthma and chronic respiratory symptoms: the Singapore Chinese Health Study

Occupational factors contribute to a significant fraction of respiratory disease and symptoms. The authors evaluated the role of occupational exposures in asthma, chronic bronchitis, and respiratory symptoms in the Singapore Chinese Health Study, a population-based cohort of adults aged 45-74 years at enrollment in 1993-1998. Information on occupations and occupational exposures was collected at enrollment for 52,325 subjects for whom respiratory outcomes were obtained via follow-up interviews in 1999-2004. Exposure to dusts from cotton, wood, metal, minerals, and/or asbestos was associated with nonchronic cough and/or phlegm (odds ratio (OR) = 1.19, 95% confidence interval (CI): 1.08, 1.30), chronic bronchitis (OR = 1.26, 95% CI: 1.01, 1.57), and adult-onset asthma (OR = 1.14, 95% CI: 1.00, 1.30). Cotton dust was the major contributor to respiratory symptoms. Vapor exposure from chemical solvents, dyes, cooling oils, paints, wood preservatives, and/or pesticides was associated with nonchronic cough or phlegm (OR = 1.14, 95% CI: 1.03, 1.27), chronic dry cough (OR = 1.55, 95% CI: 1.19, 2.01), and adult-onset asthma (OR = 1.34, 95% CI: 1.15, 1.56). Chemical solvents, cooling oils, and pesticides were the major contributors to respiratory symptoms. These data support the role of occupational exposures in the etiology of respiratory illness in a population-based cohort in Singapore with a low prevalence of atopic illness.

Across-shift lung function variation in cottonseed oil workers

BACKGROUND

The effects of cotton dust on pulmonary function among workers employed in cotton-spinning mills are well known. However, little data exist on the prevalence of this disorder in 'non-textile' cotton industries, including cottonseed oil mills, where high levels of exposure to dust have been demonstrated.

AIMS

This study was performed in order to determine the across-shift and across-week decline of FEV(1) and respiratory symptoms among workers in a cottonseed oil mill.

METHODS

Sixty-six exposed and 48 unexposed workers of a cottonseed oil mill in Turkey were investigated by questionnaire and lung function test (LFT). LFTs were performed before and after shift on all the working days of the week. Acute airway response was defined as an across-shift decline in FEV(1) of 5% or more on the first working day.

RESULTS

Smoking was the only risk factor for having respiratory symptoms. Acute airway response was more frequently observed in the exposed group as compared to the unexposed group (OR = 6.2, 95% CI = 2.3-16.7). The median across-shift decline in FEV(1) on the first day (120 ml) significantly improved on the following days (10, 50, 60 and -30 ml).

CONCLUSION

Smoking appears to be the main risk factor for having respiratory symptoms. Cottonseed dust may cause an acute pulmonary function decline on the first working day, but not on the following days of the week. This decline is associated with respiratory symptoms in exposed workers.

Prevalence of respiratory symptoms among workers in industries of south Tehran, Iran

OBJECTIVE

The aim of the present study was to determine the prevalence of respiratory symptoms from occupational lung hazards among workers in industries of south Tehran, IRAN.

METHODOLOGY

This was a cross-sectional study in which by multistage random sampling items on demographic characteristics, cigarette smoking, occupational history and respiratory symptoms were collected of workers.

RESULTS

The mean age of the workers was 38.5 (SD = 10.2) yr: age ranged from 19 to 70 yr. Of 880 workers under study, 252 (28.7%) were smoking. Also, it has been observed that workers exposed in the workplace with occupational chemical exposures such as dust, gas and fume pollutants. The prevalence of respiratory symptoms was cough (20.7%), phlegm (41.6%), dyspnea (41.7%), feel tightness (27.4%) and nose irritation (23.5%).

CONCLUSIONS

Occupational exposures among workers in industries of south Tehran may cause respiratory symptoms and respiratory disorders, engineering controls and industrial hygiene is recommended.

Airway responses to the inhalation of cotton dust and cotton bract extracts

BACKGROUND

Exposure to dust in the cotton industry is associated with respiratory dysfunction. Healthy subjects challenged with cotton bract extract (CBE) develop transient airway hyperresponsiveness. CBE, a major component of cotton dust, is potentially an important agent for studying byssinosis.

OBJECTIVES

To compare airway responses to cotton dust extract (CDE) and CBE in healthy subjects.

METHODS

In 21 healthy, non-smoking subjects we compared the effects of CBE and CDE in a double-blind random order, following a 10-min aerosol inhalation. The response to methacholine (MCh) 2 h following CBE or CDE was measured. Lung function was recorded using maximal (MEFV) and partial expiratory flow volume (PEFV) curves, measuring MEF at 60% of baseline vital capacity below total lung capacity [MEF40%(P)] on the PEFV curve. Responders were subjects who developed a 20% or greater fall in MEF40%(P) following extract challenge. Endotoxin levels were low for CBE (5.71 EU/mg) and CDE (31.88 EU/mg).

RESULTS

There were 18 responders to CBE and 17 responders to CDE. The average maximal falls in MEF40%(P) were 70 +/- 4.9 and 70 +/- 4.4% of baseline (nonsignificant) following CBE and CDE, respectively. All subjects enhanced their MCh response following CBE or CDE. The MCh dose which reduced MEF40%(P) by 40% was identical for CBE and CDE (1.3 microg/ml).

CONCLUSIONS

We conclude that CBE and CDE exert similar physiologic effects.

Microsomal Epoxide Hydrolase, Endotoxin, and Lung Function Decline in Cotton Textile Workers

Occupational exposure to endotoxin in organic dust may induce lung function decline. Microsomal epoxide hydrolase (mEH) detoxifies reactive oxygen species generated by endotoxin exposure, and polymorphisms of the mEH gene are associated with altered enzyme activity. We investigated the associations between mEH polymorphisms, endotoxin exposure, and lung function decline in a 20-year prospective study of 265 workers exposed to endotoxin and 234 control subjects. mEH Tyr113His and His139Arg polymorphisms were genotyped by the 5' nuclease assay, and data were analyzed using multivariate linear regression models, adjusting for important covariates. Overall, the annual decline rate of FEV1 was 29.47 ml during the 20-year follow-up. Endotoxin exposure was associated with faster lung function decline among genotypes associated with slower enzyme activity: estimates (SE) of annual FEV1 decline rates for endotoxin exposure were -2.33 (2.07), -2.81 (1.66), and -6.73 (2.83) ml for Tyr/Tyr, Tyr/His, and His/His genotype groups, respectively, for the Tyr113His polymorphism; and -1.82 (2.58) and -4.27 (1.33) ml for Arg/Arg + His/Arg and His/His genotypes, respectively, for the His139Arg polymorphism. We conclude that mEH polymorphisms modify the association between occupational endotoxin exposure and longitudinal lung function decline.