Chronic cough due to occupational factors

Assessment and Impacts of Air Pollution from Brick Kilns on Public Health in Northern Pakistan

Brick kilns add enormous quantities of organic pollutants to the air that can cause serious health issues, especially in developing countries; poor air quality is associated with community health problems, yet receives no attention in Northern Pakistan. The present study, therefore, assessed the chemical composition and investigated the impacts of air pollution from brick kilns on public health. A field-based investigation of air pollutants, i.e., PM1, PM2.5 and PM10, CO2, CO, NO, NO2, H2S, and NH3 using mobile scientific instruments was conducted in selected study area locations. Social surveys were conducted to investigate the impacts of air pollution on community health. The results reveal the highest concentrations of PM1, PM2.5, and PM10, i.e., 3377, 2305, and 3567.67 µg/m3, respectively, in specific locations. Particulate matter concentrations in sampling points exceeded the permissible limits of the Pakistan National Environmental Quality Standard and, therefore, may risk the local population’s health. The highest mean value of CO2 was 529 mg/L, and other parameters, such as CO, NO, NO2, H2S, and NH3 were within the normal range. The social survey’s findings reveal that particulate matter was directly associated with respiratory diseases such as asthma, which was reported in all age groups selected for sampling. The study concluded by implementing air pollution reduction measures in brick kiln industries to protect the environment and community health. In addition, the region’s environmental protection agency needs to play an active role in proper checking and integrated management to improve air quality and protect the community from air hazards.

Impact of Air Pollution Generated by Brick Kilns on the Pulmonary Health of Workers

BACKGROUND

Brick kiln workers are often not aware of the health effects of their working environment and health-related respiratory problems. There have been few studies on the relationship between brick kiln pollution and its health impact on brick kiln workers.

OBJECTIVES

The present study measured the association of brick kiln contamination with severe respiratory problems and lung function among brick kiln workers in the Kasur district, Pakistan.

METHODS

Air quality variables (PM_2.5, PM₁₀, sulfur dioxide (SO₂), nitrogen dioxide (NO₂) and volatile organic compounds (VOCs)) were monitored during operations in brick kiln modulation and kiln areas. Workers (n=60) were selected for participation if they were between the ages of 18 and 60 and had been working in brick kilns for at least one year and gave consent to participate. Their lung function was measured.

RESULTS

The average concentrations of measured air quality variables for all working sites were found to exceed the World Health Organization (WHO) and National Ambient Air Quality Standard (NAAQS) guidelines. These high values of brick kiln pollutants were associated with a significant decrease in spirometric values (forced vital capacity (FVC), forced expiratory volume in one second (FEV1), peak expiratory flow (PEF), and average flow between 25% and 75% of the FVC (FEF2575)) among workers and revealed that 78.33% of workers had abnormal lung function with 5% obstructive and 95% restrictive impairments. Occurrences of pulmonary problems like frequent cough (50%), chronic cough (11.67%), frequent phlegm (21.67%), chronic phlegm (11.67%), frequent wheezing (20%), chronic wheezing (15%), shortness of breath grade-I & grade-II (38.33%) and self-reported asthma (3.33%) were also found among the workers.

CONCLUSIONS

Pollution from brick kiln operations was significantly high and associated with respiratory problems as well as a decrease in lung function. There was a clear correlation between pulmonary function in workers with brick kiln contamination.

PARTICIPANT CONSENT

Obtained.

ETHICS APPROVAL

This study was approved by the Bioethics Committee of the Department of Zoology, University of the Punjab, Lahore, Pakistan (Ref.1443-UZ).

COMPETING INTERESTS

The authors declare no competing financial interests.

Irritant-Induced Chronic Cough Triggers: A Scoping Review and Clinical Checklist

Purpose The primary aim of this review was to identify environmental irritants known to trigger chronic cough through the life span and develop a comprehensive clinically useful irritant checklist. Method A scoping review was conducted using the Preferred Reporting Items for Systematic Review and Meta-Analysis Extension for Scoping Reviews, checklist, and explanation. English-language, full-text resources were identified through Medline, PsycINFO, SPORTDiscus, Web of Science, and ProQuest Dissertations and Theses Global. Results A total of 1,072 sources were retrieved; of these, 109 were duplicates. Titles of abstracts of 963 articles were screened, with 295 selected for full-text review. Using the exclusion and inclusion criteria listed, 236 articles were considered eligible and 214 different triggers were identified. Triggers were identified from North America, Europe, Africa, Asia, and Australia. Occupational exposures were also delineated. Conclusions A clinically useful checklist of both frequently encountered triggers and idiosyncratic or rare triggers was developed. The clinical checklist provides a unique contribution to streamline and standardize clinical assessment of irritant-induced chronic cough. The international scope of this review extends the usefulness of the clinical checklist to clinicians on most continents.

Variola minor in coalfield areas of England and Wales, 1921-34: Geographical determinants of a national smallpox epidemic that spread out of effective control

This paper uses techniques of binary logistic regression to identify the spatial determinants of the last national epidemic of smallpox to spread in England and Wales, the variola minor epidemic of 1921-34. Adjusting for age and county-level variations in vaccination coverage in infancy, the analysis identifies a dose-response gradient with increasing odds of elevated smallpox rates in local government areas with (i) medium (odds ratio [OR] = 5.32, 95% Confidence Interval [95% CI] 1.96-14.41) and high (OR = 11.32, 95% CI 4.20-31.59) coal mining occupation rates and (ii) medium (OR = 16.74, 95% CI 2.24-125.21) and high (OR = 63.43, 95% CI 7.82-497.21) levels of residential density. The results imply that the spatial transmission of variola virus was facilitated by the close spatial packing of individuals, with a heightened transmission risk in coal mining areas of the country. A syndemic interaction between common respiratory conditions arising from exposure to coal dust and smallpox virus transmission is postulated to have contributed to the findings. We suggest that further studies of the geographical intersection of coal mining and acute infections that are transmitted via respiratory secretions are warranted.

Occupational and Environmental Contributions to Chronic Cough in Adults: Chest Expert Panel Report

BACKGROUND

In response to occupational and environmental exposures, cough can be an isolated symptom reflecting exposure to an irritant with little physiological consequence, or it can be a manifestation of more significant disease. This document reviews occupational and environmental contributions to chronic cough in adults, focusing on aspects not previously covered in the 2006 ACCP Cough Guideline or our more recent systematic review, and suggests an approach to investigation of these factors when suspected.

METHODS

MEDLINE and TOXLINE literature searches were supplemented by articles identified by the cough panel occupational and environmental subgroup members, to identify occupational and environmental aspects of chronic cough not previously covered in the 2006 ACCP Cough Guideline. Based on the literature reviews and the Delphi methodology, the cough panel occupational and environmental subgroup developed guideline suggestions that were approved after review and voting by the full cough panel.

RESULTS

The literature review identified relevant articles regarding: mechanisms; allergic environmental causes; chronic cough and the recreational and involuntary inhalation of tobacco and marijuana smoke; nonallergic environmental triggers; laryngeal syndromes; and occupational diseases and exposures. Consensus-based statements were developed for the approach to diagnosis due to a lack of strong evidence from published literature.

CONCLUSIONS

Despite increased understanding of cough related to occupational and environmental triggers, there remains a gap between the recommended assessment of occupational and environmental causes of cough and the reported systematic assessment of these factors. There is a need for further documentation of occupational and environmental causes of cough in the future.

EAACI Position Paper on assessment of cough in the workplace

Cough is a nonspecific and relatively common symptom that can present difficulties in diagnosis and management, particularly when it is reported to be associated with the workplace. The present consensus document, prepared by a taskforce of the Interest Group on Occupational Allergy of the European Academy of Allergy and Clinical Immunology by means of a nonsystematic review of the current literature, is intended to provide a definition and classification of work-related chronic cough (WRCC) to assist the daily practice of physicians facing with this symptom. The review demonstrates that several upper and lower airway work-related diseases may present with chronic cough; hence, the possible link with the workplace should always be considered. Due to the broad spectrum of underlying diseases, a multidisciplinary approach is necessary to achieve a definite diagnosis. Nevertheless, more epidemiological studies are necessary to estimate the real prevalence and risk factors for WRCC, the role of exposure to environmental and occupational sensitizers and irritants in its pathogenesis and the interaction with both upper and lower airways. Finally, the best management option should be evaluated in order to achieve the best outcome without adverse social and financial consequences for the worker.

Chronic Obstructive Pulmonary Disease in Never-Smoking Bricklayers

Background: Chronic obstructive pulmonary disease (COPD) due to occupational exposures remains an important public health problem taking significant toll on the global burden of the disease.Aim: In order to assess chronic prevalence and characteristics of COPD in bricklaying we performed a cross-sectional study including 47 never-smoking male bricklayers (aged 34 to 57 years) and an equal number of never-smoking male office workers studied as a control.Methods: 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 bricklayers with significant difference for cough and phlegm. Majority of the chronic respiratory symptoms in bricklayers were work-related. The mean values of all measured spirometric parameters in bricklayers were significantly lower than in office workers. The prevalence of COPD was significantly higher in bricklayers than in office workers (14.9% vs. 4.3%, P = 0.034). COPD in both examined groups was close related to age over 45 years, while in bricklayers significant association was registered for duration of occupational exposure longer than 20 years and work-related respiratory symptoms.Conclusion: Our findings support data about relationship between occupational exposure to inorganic dust and fumes in construction workers and persistent airflow limitation.

Nanoparticles and cars - analysis of potential sources

Urban health is potentially affected by particle emissions. The potential toxicity of nanoparticles is heavily debated and there is an enormous global increase in research activity in this field. In this respect, it is commonly accepted that nanoparticles may also be generated in processes occurring while driving vehicles. So far, a variety of studies addressed traffic-related particulate matter emissions, but only few studies focused on potential nanoparticles.Therefore, the present study analyzed the literature with regard to nanoparticles and cars. It can be stated that, to date, only a limited amount of research has been conducted in this area and more studies are needed to 1) address kind and sources of nanoparticles within automobiles and to 2) analyse whether there are health effects caused by these nanoparticles.

Car indoor air pollution - analysis of potential sources

The population of industrialized countries such as the United States or of countries from the European Union spends approximately more than one hour each day in vehicles. In this respect, numerous studies have so far addressed outdoor air pollution that arises from traffic. By contrast, only little is known about indoor air quality in vehicles and influences by non-vehicle sources.Therefore the present article aims to summarize recent studies that address i.e. particulate matter exposure. It can be stated that although there is a large amount of data present for outdoor air pollution, research in the area of indoor air quality in vehicles is still limited. Especially, knowledge on non-vehicular sources is missing. In this respect, an understanding of the effects and interactions of i.e. tobacco smoke under realistic automobile conditions should be achieved in future.

Ships, ports and particulate air pollution - an analysis of recent studies

The duration of use is usually significantly longer for marine vessels than for roadside vehicles. Therefore, these vessels are often powered by relatively old engines which may propagate air pollution. Also, the quality of fuel used for marine vessels is usually not comparable to the quality of fuels used in the automotive sector and therefore, port areas may exhibit a high degree of air pollution. In contrast to the multitude of studies that addressed outdoor air pollution due to road traffic, only little is known about ship-related air pollution. Therefore the present article aims to summarize recent studies that address air pollution, i.e. particulate matter exposure, due to marine vessels. It can be stated that the data in this area of research is still largely limited. Especially, knowledge on the different air pollutions in different sea areas is needed.

Editorial: Experimental models of asthma

Since 2002, a workshop entitled “Asthma in animal models” has been held once a year in Hannover, Germany. It is organized by the Fraunhofer Institute of Toxicology and Experimental Medicine in collaboration with the collaborative research centre “Sonderforschungsbereich” 587, “Immune reactions of the lung in infection and allergy” (Hannover Medical School). The aim of these meetings is an intense scientific exchange between researchers and clinicians coming from academic or industrial background. Over the years the topics within the extensive field of asthma and COPD have ranged from methodological aspects to the influence of infections and environmental factors up to perspectives in the development of new therapeutic strategies.

Cough: an unmet clinical need

Cough is among the most common complaints for which patients worldwide seek medical attention. Thus, the evaluation and treatment of cough result in tremendous financial expenditure and consumption of health care resources. Yet, despite the clinical significance of cough, research efforts aimed at improving diagnostic capabilities and developing more effective therapeutic agents have been, to date, disappointing in their limited scope and outcomes. Acute cough due to the common cold represents the most common type of cough. Currently, available medications for the symptomatic management of acute cough are inadequate due to lack of proven efficacy and/or their association with undesirable or intolerable side effects at anti-tussive doses. Subacute cough, often representing a prolonged post-viral response, is typically refractory to standard anti-tussive therapy. Few clinical trials have evaluated therapeutic options for subacute cough. Diagnostic challenges facing the clinician in the management of chronic cough include the determination of whether symptoms of upper airway cough syndrome (formerly, postnasal drip syndrome) or gastro-oesophageal reflux disease are indeed the underlying cause of cough. Chronic, refractory unexplained (formerly, idiopathic) cough must be distinguished from cough that has not been fully evaluated and treated according to current guideline recommendations. Eagerly awaited are new safe and effective anti-tussive agents for use when cough suppression is desired, regardless of underlying aetiology of cough, as well as practical, validated ambulatory cough counters to aid clinical assessment and future research in the field of cough.

Chronic cough – occupational considerations

Chronic cough is a common symptom in a wide range of respiratory conditions, and may also occur as a result of upper airway or gastro-esophageal problems. Whilst chronic cough of any cause may be exacerbated by work, in some cases it has a direct occupational cause, resulting from a harmful acute or chronic workplace exposure. Such occupational conditions may only be suspected by taking a detailed occupational history, and directly asking employed patients whether their cough improves away from work. Early and accurate diagnosis, linked with tailored drug therapy, modification of workplace exposures, and expert compensation advice is likely to offer the best outcome for this group of patients.

Outcome of occupational latex allergy--work ability and quality of life

Objective

The quality of life (QOL) and work ability of health care workers allergic to natural rubber latex (NRL) were assessed after implementation of regulations on powder-free NRL gloves in Germany.

Methods

196 HCW with reported NRL allergy answered a questionnaire (response rate 58%) containing the Work Ability Index (WAI), Mini Asthma Quality of Life Questionnaire (MiniAQLQ), and Dermatology Life Quality Index (DLQI).

Results

63.2% still had NRL-related symptoms during the last 6 month. However on a scale from 0 to 10, the intensity of NRL-related symptoms decreased from 8.5 before to 2.3 after implementation of regulations on powder-free NRL gloves. A higher number of subjects were able to avoid NRL in the private than in the work environment (85% vs. 61%). NRL-related symptoms decreased and WAI increased with successful avoidance of NRL at workplace (b = 0.23, p = 0.003). QOL was only little affected by NRL allergy (mean: MiniAQLQ = 6.0; DLQI = 4.1).

Conclusions

Although there was improvement after implementation of powder-free NRL gloves, there is still a considerable number of HCW with NRL-related symptoms. Further investigations on latex avoidance and the cause of persisiting allergic symptoms in HCW with NRL allergy are therefore needed.

Respiratory function and bronchial responsiveness among industrial workers exposed to different classes of occupational agents: a study from Algeria

Occupational exposures play a role in the onset of several chronic airway diseases. We investigated, in a cross-sectional study, lung function parameters and bronchial hyper-responsiveness to histamine in workers exposed to different airborne compounds.

The study group totalled 546 male subjects of whom 114 were exposed to welding fumes, 106 to solvents, 107 to mineral dust, 97 to organic dust and 123 without known exposure to airway irritants. A questionnaire was administered and spirometry and bronchial responsiveness to histamine were assessed by one observer, in the morning before work to prevent effects of acute exposure.

The mean (SD) age of the participants was 39.3 (7.8) years, with a mean duration of employment of 13.8 (6.6) years. Both before and after adjustment for smoking status, forced expiratory volume in 1 second (FEV₁, expressed as % predicted) was lower in welders -4.0% (95% confidence interval [CI], -6.3 to -1.8; p = 0.01) and workers exposed to solvents -5.6% (CI: -7.9 to -3.3; p = 0.0009) than in control subjects. Furthermore, solvent workers had an odds ratio of 3.43 (95% CI: 1.09–11.6; p = 0.037) for bronchial hyperresponsiveness compared with the reference group.

The higher prevalence of bronchial hyperresponsiveness in solvent workers adds to the growing body of evidence of adverse respiratory effects of occupational solvent exposure. These results point to the necessity of preventive measures in solvent workers to avoid these adverse respiratory effects.

Analysis and evaluation of environmental tobacco smoke exposure as a risk factor for chronic cough

Exposure to environmental tobacco smoke (ETS) and active tobacco smoking has been shown to increase symptoms of bronchial asthma such as bronchoconstriction but effects on other respiratory symptoms remain poorly assessed. Current levels of exposure to tobacco smoke may also be responsible for the development of chronic cough in both children and adults. The present study analyses the effects of tobacco smoke exposure as potential causes of chronic cough. A panel of PubMed-based searches was performed relating the symptom of cough to various forms of tobacco smoke exposure. It was found that especially prenatal and postnatal exposures to ETS have an important influence on children's respiratory health including the symptom of cough. These effects may be prevented if children and pregnant women are protected from exposure to ETS. Whereas the total number of studies adressing the relationship between cough and ETS exposure is relatively small, the present study demonstrated that there is a critical amout of data pointing to a causative role of environmental ETS exposure for the respiratory symptom of cough. Since research efforts have only targeted this effect to a minor extent, future epidemiological and experimental studies are needed to further unravel the relation between ETS and cough.

The toxicity of cadmium and resulting hazards for human health

Cadmium (Cd) has been in industrial use for a long period of time. Its serious toxicity moved into scientific focus during the middle of the last century. In this review, we discuss historic and recent developments of toxicological and epidemiological questions, including exposition sources, resorption pathways and organ damage processes.

Analysis of airway secretions in a model of sulfur dioxide induced chronic obstructive pulmonary disease (COPD)

Hypersecretion and chronic phlegm are major symptoms of chronic obstructive pulmonary disease (COPD) but animal models of COPD with a defined functional hypersecretion have not been established so far. To identify an animal model of combined morphological signs of airway inflammation and functional hypersecretion, rats were continuously exposed to different levels of sulfur dioxide (SO2, 5 ppm, 10 ppm, 20 ppm, 40 ppm, 80 ppm) for 3 (short-term) or 20–25 (long-term) days. Histology revealed a dose-dependent increase in edema formation and inflammatory cell infiltration in short-term-exposed animals. The submucosal edema was replaced by fibrosis after long-term-exposure. The basal secretory activity was only significantly increased in the 20 ppm group. Also, stimulated secretion was significantly increased only after exposure to 20 ppm. BrdU-assays and AgNOR-analysis demonstrated cellular metaplasia and glandular hypertrophy rather than hyperplasia as the underlying morphological correlate of the hypersecretion.

In summary, SO2-exposure can lead to characteristic airway remodeling and changes in mucus secretion in rats. As only long-term exposure to 20 ppm leads to a combination of hypersecretion and airway inflammation, only this mode of exposure should be used to mimic human COPD. Concentrations less or higher than 20 ppm or short term exposure do not induce the respiratory symptom of hypersecretion. The present model may be used to characterize the effects of new compounds on mucus secretion in the background of experimental COPD.

Analysing the causes of chronic cough: relation to diesel exhaust, ozone, nitrogen oxides, sulphur oxides and other environmental factors

Air pollution remains a leading cause of many respiratory diseases including chronic cough. Although episodes of incidental, dramatic air pollution are relatively rare, current levels of exposure of pollutants in industrialized and developing countries such as total articles, diesel exhaust particles and common cigarette smoke may be responsible for the development of chronic cough both in children and adults. The present study analyses the effects of common environmental factors as potential causes of chronic cough. Different PubMed-based researches were performed that related the term cough to various environmental factors. There is some evidence that chronic inhalation of diesel can lead to the development of cough. For long-term exposure to nitrogen dioxide (NO2), children were found to exhibit increased incidences of chronic cough and decreased lung function parameters. Although a number of studies did not show that outdoor pollution directly causes the development of asthma, they have demonstrated that high levels pollutants and their interaction with sunlight produce ozone (O3) and that repeated exposure to it can lead to chronic cough. In summary, next to the well-known air pollutants which also include particulate matter and sulphur dioxide, a number of other indoor and outdoor pollutants have been demonstrated to cause chronic cough and therefore, environmental factors have to be taken into account as potential initiators of both adult and pediatric chronic cough.

Occupational medicine and toxicology

This editorial is to announce the Journal of Occupational Medicine and Toxicology, a new Open Access, peer-reviewed, online journal published by BioMed Central. Occupational medicine and toxicology belong to the most wide ranging disciplines of all medical specialties. The field is devoted to the diagnosis, prevention, management and scientific analysis of diseases from the fields of occupational and environmental medicine and toxicology. It also covers the promotion of occupational and environmental health. The complexity of modern industrial processes has dramatically changed over the past years and today's areas include effects of atmospheric pollution, carcinogenesis, biological monitoring, ergonomics, epidemiology, product safety and health promotion. We hope that the launch of the Journal of Occupational Medicine and Toxicology will aid in the advance of these important areas of research bringing together multi-disciplinary research findings.

Chronic cough due to occupational factors

Within the large variety of subtypes of chronic cough, either defined by their clinical or pathogenetic causes, occupational chronic cough may be regarded as one of the most preventable forms of the disease. Next to obstructive airway diseases such as asthma or chronic obstructive pulmonary disease, which are sometimes concomitant with chronic cough, this chronic airway disease gains importance in the field of occupational medicine since classic fiber-related occupational airway diseases will decrease in the future.

Apart from acute accidents and incidental exposures which may lead to an acute form of cough, there are numerous sources for the development of chronic cough within the workplace. Over the last years, a large number of studies has focused on occupational causes of respiratory diseases and it has emerged that chronic cough is one of the most prevalent work-related airway diseases. Best-known examples of occupations related to the development of cough are coal miners, hard-rock miners, tunnel workers, or concrete manufacturing workers.

As chronic cough is often based on a variety of non-occupational factors such as tobacco smoke, a distinct separation into either occupational or personally -evoked can be difficult. However, revealing the occupational contribution to chronic cough and to the symptom cough in general, which is the commonest cause for the consultation of a physician, can significantly lead to a reduction of the socioeconomic burden of the disease.