Exposure-response relationship between endotoxin exposure and lung function impairment in cotton textile workers

Health disorders and safety measures among workers in Tanta Flax and Oil Company, Egypt

Flax industry has an adverse effect on health status of exposed workers especially in developing countries with lack of appropriate safety measures to identify the health hazards, health disorders among workers in flax and oil company, and to assess the applied safety measures in the factory. A cross sectional study was conducted in Tanta Flax and Oil Company in Egypt. The company includes eight factories which are divided into four departments according to the manufacturing end products. The study was conducted from August 2018 to December 2019 on 353 workers out of 400 workers. An interview questionnaire and clinical medical examination were done to assess the health status of exposed workers. Check list from occupational safety and health administration (OSHA) standards was filled by researcher to check safety measures in work place environment. Respiratory manifestations were detected in 65% of the examined workers in flax manufacturing departments while allergic manifestations were more obvious in formaldehyde factory department. Approximately one quarter of workers complained that personal protective equipment's are not available. Regarding the mask for dust, nearly half (44.5%) of the workers rarely used them, and only 7.1% always use them. Byssinosis was obvious among workers in flax manufacturing and particle board manufacturing department with statistically significant differences between the four departments, in which 36.9% and 24.1% of workers in these two departments suffered from chest tightness, respectively. The safety measures were inadequate in flax manufacturing departments and to somewhat sufficient in formaldehyde factory department. Most of exposed workers had inadequate health status due to lack of standard safety measures. Therefore, periodic medical examination should be done regularly with investigation of pulmonary functions of exposed workers with application of high level of safety measure standards in the work place environment.

Validity of reported indicators of pesticide exposure and relevance for cytotoxic and genotoxic effects on buccal cells

Higher rates of nuclear anomalies in buccal cells of coffee workers exposed to pesticides in comparison to their unexposed peers were detected in our field study. Here, we extend our findings by examining other exposure indicators in this sample. Occupational exposure of 38 exposed and 33 non-exposed farmworkers was assessed as exposure days in the last month (0-25 days) and as years of exposure (0-47 years). Genotoxic and cytotoxic markers in buccal cells were analysed following standard procedures for buccal micronucleus cytome assay. Both exposure markers were associated with a higher frequency of nuclear anomalies with odds ratios more than 1. After restricting the analysis to the exposed workers only, this association remained only with the marker of recent exposure. In a secondary analysis also environmental exposure defined as proximity of the home to the nearest sprayed field (distance <1000 m) was assessed. Proximity led to increased rates (with odds ratios more than 3) of genotoxic but not cytotoxic nuclear anomalies. Reported recent frequency and intensity of pesticide use and application are a valid exposure marker relevant for cytological pathologies in the buccal mucosa. The exposure metric for environmental exposure was rather crude and confounding by some unmeasured factor cannot be fully excluded. Nevertheless, simple exposure indicators that can even be obtained under rather difficult field conditions do provide health-relevant and valid information.

Personal inhalable dust and endotoxin exposure among workers in an integrated textile factory

The aim of this study was to determine personal exposure to inhalable dust and endotoxin levels among workers in an integrated cotton-processing textile factory and exposure variability across the different work sections. Full shift measurements were carried out using inhalable conical samplers with 37 mm glass-fiber filters. Personal inhalable dust was determined gravimetrically, and endotoxin levels were analyzed by kinetic chromogenic Limulus Amebocytes Lysate assay. The geometric means of personal dust and endotoxin concentrations were 0.75 mg·m^-3 and 831 EU·m^-3, respectively. The highest dust and endotoxin concentrations were observed in carding section (1.34 mg·m^-3 and 6,381 EU·m^-3, respectively). Altogether, 11% of dust and 89% of endotoxin samples exceeded workplace exposure limits. This study showed a moderate correlation between inhalable dust and endotoxin (r = 0.450, p < 0.001). Our findings indicate that low dust exposure does not guarantee a low exposure to endotoxin.

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.

Inactivation of airborne bacteria using different UV sources: Performance modeling, energy utilization, and endotoxin degradation

Airborne bacteria-containing bioaerosols have attracted increased research attention on account of their adverse effects on human health. Ultraviolet germicidal irradiation (UVGI) is an effective method to inactivate airborne microorganisms. The present study models and compares the inactivation performance of three UV sources in the UVGI for aerosolized Escherichia coli. Inactivation efficiency of 0.5, 2.2 and 3.1 logarithmic order was obtained at an exposure UV dose of 370 J/m³ under UVA (365 nm), UVC (254 nm) and UVD (185 nm) sources, respectively. A Beer-Lambert law-based model was developed and validated to compare the inactivation performances of the UV sources, and modeling enabled prediction of inactivation efficiency and analysis of the sensitivity of several parameters. Low influent E. coli concentrations and high UV doses resulted in high energy consumption (EC). The change in airborne endotoxin concentration during UV inactivation was analyzed, and UVC and UVA irradiation showed no marked effect on endotoxin degradation. By contrast, both free and bound endotoxins could be removed by UVD treatment, which is attributed to the ozone generated by the UVD source. The results of this study can provide a better understanding of the air disinfection and airborne endotoxin removal processes.

Effect of Organic Dust Exposure on Pulmonary Functions in Workers of Vegetable Market with Special Reference to its Microbial Content

Context:

Wholesale vegetable market is a rich source of generation of organic dust as loads of fruits and vegetables are loaded and unloaded here daily. Thus, regular workers are exposed to this organic dust for a considerable period of time depending on their work schedule. This study was planned to determine the microbial status of organic dust and to explore its association with pulmonary functions in the workers of wholesale vegetable market in Rishikesh.

Materials and Methods:

It was a cross-sectional exploratory/observational study. Thirty-five apparently healthy adult males were selected from vegetable market having no history of any chronic illness. Smokers and alcoholic were excluded from the study. The same number of age- and sex-matched controls with the same exclusion criteria were recruited from workers not working in the vegetable market and also not exposed to any other kinds of organic dust. Microbial culture of air in the vegetable market was done. It was compared with the microbial status of air in the working place of controls. Pulmonary functions of all the workers were performed with the help of digital spirometer (Helios 401).

Results:

Bacterial and fungal concentration was found to be significantly higher in the air of vegetable market as compared to air in the workplace of controls (such as coagulase-negative staphylococci >25 colony-forming unit (CFU) at incubation temperature vs. 10–12 CFU at incubation temperature, significant growth of Mucor, Aspergillus niger, and Candida nonalbicans in vegetable market as compared to workplace of controls). Pulmonary function parameters (percentage forced expiratory volume in 1^st s (FEV₁), percentage predicted forced expiratory flow in mid-half of expiration, and FEV₁) of workers exposed to organic dust in vegetable market were also significantly lower (P < 0.05).

Conclusion:

Exposure of organic dust is associated with compromised pulmonary functions and there is a need of formulation of safety guidelines.

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.

Exposure to high endotoxin concentration increases wheezing prevalence among laboratory animal workers: a cross-sectional study

Background

Endotoxin from Gram-negative bacteria are found in different concentrations in dust and on the ground of laboratories dealing with small animals and animal houses.

Methods

Cross-sectional study performed in workplaces of two universities. Dust samples were collected from laboratories and animal facilities housing rats, mice, guinea pigs, rabbits or hamsters and analyzed by the “Limulus amebocyte lysate” (LAL) method. We also sampled workplaces without animals. The concentrations of endotoxin detected in the workplaces were tested for association with wheezing in the last 12 months, asthma defined by self-reported diagnosis and asthma confirmed by bronchial hyperresponsiveness (BHR) to mannitol.

Results

Dust samples were obtained at 145 workplaces, 92 with exposure to animals and 53 with no exposure. Exposed group comprised 412 subjects and non-exposed group comprised 339 subjects. Animal-exposed workplaces had higher concentrations of endotoxin, median of 34.2 endotoxin units (EU) per mg of dust (interquartile range, 12.6–65.4), as compared to the non-exposed group, median of 10.2 EU/mg of dust (interquartile range, 2.6–22.2) (p < 0.001). The high concentration of endotoxin (above whole sample median, 20.4 EU/mg) was associated with increased wheezing prevalence (p < 0.001), i.e., 61 % of workers exposed to high endotoxin concentration reported wheezing in the last 12 months compared to 29 % of workers exposed to low endotoxin concentration. The concentration of endotoxin was not associated with asthma report or with BHR confirmed asthma.

Conclusion

Exposure to endotoxin is associated with a higher prevalence of wheezing, but not with asthma as defined by the mannitol bronchial challenge test or by self-reported asthma. Preventive measures are necessary for these workers.

Industrial hygiene, occupational safety and respiratory symptoms in the Pakistani cotton industry

OBJECTIVES

In the cotton industry of Pakistan, 15 million people are employed and exposed to cotton dust, toxic chemicals, noise and physical hazards. The aim of this study was to determine the prevalence of health symptoms, particularly respiratory symptoms, and to measure cotton dust and endotoxin levels in different textile factories of Faisalabad, Pakistan.

METHODS

A cross-sectional investigation was performed in a representative sample of 47 cotton factories in the Faisalabad region in Punjab, Pakistan. Respiratory symptoms of 800 workers were documented by questionnaire. Occupational safety in the factories was assessed by a trained expert following a checklist, and dust and endotoxin levels in different work areas were measured.

RESULTS

Prevalence of respiratory disease symptoms (fever, shortness of breath, chest tightness and cough) was generally high and highest in the weaving section of the cotton industry (20-40% depending on symptoms). This section also displayed the poorest occupational safety ratings and the highest levels of inhalable cotton dust (mean±SD 4.6±2.5 vs 0.95±0.65 mg/m(3) in compact units). In contrast, endotoxin levels were highest in the spinning section (median 1521 EU/m(3)), where high humidity is maintained.

CONCLUSIONS

There are still poor working conditions in the cotton industry in Pakistan where workers are exposed to different occupational hazards. More health symptoms were reported from small weaving factories (power looms). There is a dire need for improvements in occupational health and safety in this industrial sector with particular focus on power looms.

Chronic Obstructive Pulmonary Disease in Never-Smoking Female Workers Exposed to Cotton Dust

AIM: Textile workers in their work environment are exposed to airborne particulate from natural and synthetic origin. In the present study we aimed at assessment of prevalence and characterstics of  COPD in never-smoking female workers employed at cotton weaving sector in textile manufacture.MATERIAL AND METHODS: In order to assess chronic prevalence and characteristics of chronic obstructive pulmonary disease (COPD) in textile industry we performed a cross-sectional study including 47 never-smoking female cotton workers (aged 36 to 56 years) and an equal number of never-smoking female office workers studied as a control. Evaluation of examined subjects consisted of completion of a questionnaire, baseline spirometry, and bronchodilator reversibility testing.RESULTS: We found higher prevalence of respiratory symptoms in cotton workers with significant difference for phlegm and dyspnea. Majority of the chronic respiratory symptoms in cotton workers were work-related. With exception of the mean value of forced vital capacity (FVC), the mean values of all other measured spirometric parameters in cotton workers were significantly lower than in office workers. The prevalence of COPD was significantly higher in cotton workers than in office workers (11.4% vs. 2.3%, P = 0,027). COPD in cotton workers was significantly associated with age higher than 45 years and with duration of exposure longer than 20 years.CONCLUSION: Our findings support data about relationship between occupational exposure to organic dust in textile workers and persistent airflow limitation.

Indoor exposure to airborne endotoxin: a review of the literature on sampling and analysis methods

Assessment of exposure to airborne endotoxins has been studied for several years, especially in occupational environments, but a large number of procedures are used for sampling and analysis. This lack of standardization makes it very difficult to compare results and set internationally accepted threshold limit values (TLVs) or occupational exposure limits (OELs) for endotoxin exposure. This paper reviews the methods reported, using advanced bibliographical search techniques: 82 papers published from 2004 to the present were selected to analyze methods for the assessment of human exposure to airborne endotoxins, with particular reference to occupational settings, and to examine their performance and critical points. Only few studies have focused on the standardization of sampling and analysis methods. The European Committee for Standardization Guidelines coincide with the procedures most frequently applied, but this does not guarantee the best results in terms of recovery and reproducibility. The factor that mainly affects endotoxin measurements is the extraction method, the main concern being the presence in the samples of a fraction insoluble in aqueous media. If substantial differences in the proportions of this fraction in different environments are confirmed in the future, the contribution of insoluble endotoxins cannot be neglected.

Pulmonary function reductions among potentially susceptible subgroups of agricultural workers in Colorado and Nebraska

OBJECTIVE

Organic dust inhalation has been associated with adverse respiratory responses among agricultural workers. We evaluated factors that may confer increased susceptibility to these health effects.

METHODS

We quantified personal work shift exposures to inhalable dust, endotoxin, and its 3-hydroxy fatty acid constituents, and evaluated changes in pulmonary function among 137 grain elevator, cattle feedlot, dairy, and corn farm workers.

RESULTS

Increased dust exposure was associated with work shift reductions in lung function. Although interpretation is limited because of small samples, a suggestion of stronger exposure-response relationships was observed among smokers, as well as workers reporting pesticide/herbicide application, asthma, or allergies, and those with genetic polymorphisms (TLR4) (Pinteraction ≤ 0.05).

CONCLUSIONS

A better understanding of factors leading to increased susceptibility of adverse respiratory outcomes is needed to optimize exposure reduction strategies and develop more comprehensive wellness programs.

Measurement of endotoxins in bioaerosols at workplace: a critical review of literature and a standardization issue

Endotoxins are lipopolysaccharides found in the outer membrane of most Gram-negative bacteria and cyanobacteria. Worker exposure to endotoxins has been shown in a number of work situations and is associated with both respiratory and systemic pathologies. The lack of an occupational exposure limit is mainly due to the absence of a standard protocol at the international level for sampling and analyzing airborne endotoxins. The bibliographic review in this article takes an exhaustive look at the current knowledge on measuring airborne endotoxins. It shows that, despite several reference documents at the international level, the methods used to measure endotoxin exposure differ considerably from one laboratory to another. Standardization is necessary to reduce interlaboratory variability and, ultimately, to improve the use of interstudy data. The bibliographic review presents the current status of standardization for airborne endotoxin measurement methods in the workplace and summarizes areas for further research. This article is both a reference document for all operators wishing to use such methods and a working document to build international consensus around the measurement of airborne endotoxins.

Bespoke latex allergen testing improves assessment of respiratory symptoms in textile-braiding workers

BACKGROUND

Latex allergy is poorly understood in latex-exposed textile workers.

METHODS

A cross-sectional study was carried out to better characterize respiratory symptoms, using personal breathing zone latex allergen measurement and specific IgE to latex allergens.

RESULTS

Forty-four of the 86 (51% participation rate) participated. Ten of 39 workers who gave a blood sample (25.6%) were found to have IgE to at least one workplace allergen (5/39 positive to either latex braiding coated with silica or talc, 4/39 were positive to the dyed cotton extract, and 1/39 to latex braiding coated with silica or talc and dyed cotton extract), whilst only 2 of these 10 had specific IgE to the commercial latex extract.

CONCLUSIONS

The presence of symptoms with evidence of sensitization was strongly dictated by current latex exposure. Bespoke workplace allergen IgE testing identified cases of WR respiratory symptoms with sensitization that otherwise would not have been identified.

Maize pollen is an important allergen in occupationally exposed workers

Background

The work- or environmental-related type I sensitization to maize pollen is hardly investigated. We sought to determine the prevalence of sensitization to maize pollen among exposed workers and to identify the eliciting allergens.

Methods

In July 2010, 8 out of 11 subjects were examined who were repeatedly exposed to maize pollen by pollinating maize during their work in a biological research department. All 8 filled in a questionnaire and underwent skin prick testing (SPT) and immune-specific analyses.

Results

5 out of the 8 exposed subjects had repeatedly suffered for at least several weeks from rhinitis, 4 from conjunctivitis, 4 from urticaria, and 2 from shortness of breath upon occupational exposure to maize pollen. All symptomatic workers had specific IgE antibodies against maize pollen (CAP class ≥ 1). Interestingly, 4 of the 5 maize pollen-allergic subjects, but none of the 3 asymptomatic exposed workers had IgE antibodies specific for grass pollen. All but one of the maize pollen-allergic subjects had suffered from allergic grass pollen-related symptoms for 6 to 11 years before job-related exposure to maize pollen. Lung function testing was normal in all cases. In immunoblot analyses, the allergenic components could be identified as Zea m 1 and Zea m 13. The reactivity is mostly caused by cross-reactivity to the homologous allergens in temperate grass pollen. Two sera responded to Zea m 3, but interestingly not to the corresponding timothy allergen indicating maize-specific IgE reactivity.

Conclusion

The present data suggest that subjects pollinating maize are at high risk of developing an allergy to maize pollen as a so far underestimated source of occupational allergens. For the screening of patients with suspected maize pollen sensitization, the determination of IgE antibodies specific for maize pollen is suitable.

Lung cancer mortality in a cohort of UK cotton workers: an extended follow-up

Background:

A recent systematic review and meta-analysis suggested that occupational exposure to endotoxins protects against lung cancer. To explore this hypothesis further, the follow-up of mortality of a cohort of 3551 workers, who were employed in the British cotton industry during 1966–1971, was extended by 23 years.

Methods:

Subjects had originally been recruited to a survey of respiratory disease, which collected information about occupation and smoking habits. Cumulative exposures to endotoxins were estimated from data on endotoxin levels by work areas in cotton mills. Risks of lung cancer were estimated using survival modelling.

Results:

During follow-up, 2018 deaths were recorded before the age of 90 years, including 128 deaths from lung cancer. After adjustment for smoking, hazard ratios (95% confidence intervals) for cumulative endotoxin exposures of ⩽30 000, >30 000 and ⩽200 000, >200 000 and ⩽400 000, >400 000 and ⩽600 000 and >600 000 endotoxin units (EU) m⁻³ years were 1, 0.8 (0.5–1.6), 0.7 (0.4–1.3), 0.6 (0.3–1.0) and 0.5 (0.3–0.9), respectively (P for trend=0.005).

Conclusion:

Our findings strengthen the evidence that occupational exposure to endotoxins protects against lung cancer, and suggest that the effect depends on cumulative dose and persists after exposure ceases.

Airborne endotoxin from indoor and outdoor environments: effect of sample dilution on the kinetic Limulus amebocyte lysate (LAL) assay

Airborne endotoxins in occupational environments are a potential respiratory hazard to individuals. In this study, airborne endotoxins were collected using open-face and button aerosol samplers from inside animal housing units and downwind from agricultural production sites and a wastewater treatment plant. Filter extracts were then diluted to examine the effect of interfering substances on the kinetic Limulus amebocyte lysate (LAL) assay. In most cases, the overall endotoxin concentration was shown to decrease with increasing dilution up to 1000-fold, suggesting the presence of enhancing substances in the filter extracts. This dilution-dependent effect was most prominent in the open-face endotoxin samples, while button samples displayed little effect. Using a joinpoint regression model, it was determined that a dilution factor of 50 to 100 was generally sufficient to eliminate the presence of enhancing substances. After screening the data for dilution dependent effects, the airborne endotoxin concentrations were determined. The highest endotoxin concentrations, ranging from 2841 to 49,066 endotoxin units m(-3) of air, were found inside swine farrowing and finishing barns. Airborne endotoxin concentrations were 10- to 100-fold lower inside a dairy barn and downwind of other agricultural production sites and the wastewater treatment plant. Examination of dilution-dependent effects should be considered essential when utilizing the LAL assay, especially if values are to be used for regulatory purposes.

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.

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.

Endotoxin exposure and lung cancer risk: a systematic review and meta-analysis of the published literature on agriculture and cotton textile workers

Objective

To examine the association between exposure to endotoxins and lung cancer risk by conducting a systematic review and meta-analysis of epidemiologic studies of workers in the cotton textile and agricultural industries; industries known for high exposure levels of endotoxins.

Methods

Risk estimates were extracted from studies published before 2009 that met predefined quality criteria, including 8 cohort, 1 case–cohort, and 2 case–control studies of cotton textile industry workers, and 15 cohort and 2 case–control studies of agricultural workers. Summary risk estimates were calculated using random effects meta-analyses. Potential sources of heterogeneity were explored through subgroup analyses.

Results

The summary risk of lung cancer was 0.72 (95% CI, 0.57–0.90) for textile workers and 0.62 (0.52–0.75) for agricultural workers. The relative risk of lung cancer was below 1.0 for most subgroups defined according to sex, study design, outcome, smoking adjustment, and geographic area. Two studies provided quantitative estimates of endotoxin exposure and both studies tended to support a dose–dependent protective effect of endotoxins on lung cancer risk.

Conclusion

Despite several limitations, this meta-analysis based on high-quality studies adds weight to the hypothesis that occupational exposure to endotoxin in cotton textile production and agriculture is protective against lung cancer.

Health risks due to coffee dust

OBJECTIVE

This study assessed current health risks due to occupational exposure to coffee dust.

METHODS

We performed a cross-sectional study in a coffee haulage company (n = 24), a coffee silo (n = 19), and a decaffeinating company (n = 17). Cross-shift and cross-week case histories of these employees as well as lung function values were recorded. During the handling of green coffee, measurements of airborne dust were conducted.

RESULTS

The employees in these workplaces were mainly affected by erythematous and rhinoconjunctival symptoms. They occurred especially in subjects exposed to a high dust load (> 10 mg of inhalable dust per cubic meter of air; n = 28) [Pearson chi(2) test, p = 0.020 and p = 0.023]. IgE antibodies to green coffee and castor beans were detected in 3 workers and 10 workers, respectively. The majority of them (two employees and six employees, respectively) had shown respiratory symptoms during the past 12 months. The preshift lung function values were below average but were not dependent on the level of the inhalable coffee dust exposure. Employees with a coffee dust load > 10 mg/m(3) of air showed higher unspecific bronchial responsiveness more frequently than those with lower exposures.

CONCLUSION

During the transshipment (especially during unloading) of green coffee, a high and clinically relevant exposure to irritative and sensitizing dust occurs. Therefore, efforts to reduce these dust exposures are generally recommended.

Coronary risks among seafarers aboard German-flagged ships

OBJECTIVES

Cardiovascular diseases belong to the major causes of maritime service disablement (approximately 18%). The aim of this study was to investigate the frequency of coronary risk factors in seamen on vessels sailing under the German flag and to assess the risk of coronary heart disease (CHD) dependent on job-related factors.

METHODS

Within a medical surveillance program, a cross-sectional study with interview, blood sampling, and blood pressure measurements was conducted among a total of 205 male seafarers sailing under the German flag (response 84.9%). Due to missing blood analysis, 13 seamen were excluded. The predicted 10-year risk of an acute coronary event of a study subgroup of 45 German seafarers was compared to the corresponding risk of a sample of the German working population (PROCAM study).

RESULTS

In the total sample (n = 161), 55 seamen (34.2%) had at least three CHD risk factors. The most prominent independent CHD risk factors in seafarers were hypertension (49.7%), high triglycerides (41.6%), older age (39.8%), and smoking (37.3%). Compared with non-Europeans, European seafarers were about twice as likely to have more than three risk factors after adjusting for age [OR 2.4 (95% CI 1.01-4.55)]. Particularly engine room officers and galley/operating staff were at a higher coronary risk. After standardizing for age, the German seamen investigated showed a similar predicted 10-year CHD risk as the German population of about the same age working ashore of the PROCAM study.

CONCLUSIONS

The CHD risks in seafarers should be reduced by low-fat diets, anti-smoking campaigns and blood pressure control/treatment. In spite of the seafarers' regular medical surveillance examination, their CHD risk was comparable to a reference population working ashore. Our results support the hypothesis that working on vessels may augment the risk of CHD.