Exposure to biomass smoke as a cause for airway disease in women and children

Factors related with lung functions among Orang Asli in Tasik Chini, Malaysia: a cross-sectional study

BACKGROUND

Orang Asli lifestyle and household setting may influence their health status especially respiratory system and lung functions. This cross-sectional study was carried out to investigate the status of lung functions of Orang Asli community and the associated factors.

METHODS

Data collection was carried out from November 2017 until May 2018 among 211 Orang Asli respondents aged 18 years old and above, who lived in five villages in Tasik Chini, Pahang. All respondents who fulfilled the inclusion criteria were recruited in this study. Interview-guided questionnaire was administered, and spirometry test that include Forced Expiratory Volume in one second (FEV1), Forced Vital Capacity (FVC), and Peak Expiratory Flow Rate (PEFR) was carried out. Data were analyzed using SPSS software version 23.0. In the first stage, descriptive analysis was done to describe the characteristics of the respondents. In the second stage, bivariable analysis was carried out to compare proportions. Finally, multiple logistic regression was performed to assess the effects of various independent predictors on spirometry parameters.

RESULTS

The respondents' age ranged from 18 to 71 years old in which 50.2% of them were female. The majority ethnicity in Tasik Chini was Jakun tribe (94.3%). More than half of the respondents (52.1%) were current smoker, 5.2% were ex-smoker and 41.7% were non-smoker. More than half of them (62.1%) used woodstove for cooking, compared to only 37.9% used cleaner fuel like Liquefied Petroleum Gas (LPG) as a fuel for everyday cooking activity. The lung function parameters (FEV1 and FVC) were lower than the predictive value, whereas the ratio of Forced Expiratory Volume in one second and Forced Vital Capacity (FEV1/FVC) (%) and PEFR were within the predictive value. The FEV1 levels were significantly associated with age group (18-39 years old) (p = 0.002) and presence of woodstove in the house (p = 0.004). FVC levels were significantly associated with presence of woodstove in the house (p = 0.004), whereas there were no significant associations between all factors and FEV1/FVC levels.

CONCLUSIONS

FEV1 levels were significantly associated with age group 18-39 years old, whereas FVC levels were significantly associated with the presence of woodstove in the house. Thus, environmental interventions such as replacing the use of woodstove with LPG, need to be carried out to prevent further worsening of respiratory health among Orang Asli who lived far from health facilities. Moreover, closer health monitoring is crucial especially among the younger and productive age group.

Toxicity of particles derived from combustion of Ethiopian traditional biomass fuels in human bronchial and macrophage-like cells

The combustion of traditional fuels in low-income countries, including those in sub-Saharan Africa, leads to extensive indoor particle exposure. Yet, the related health consequences in this context are understudied. This study aimed to evaluate the in vitro toxicity of combustion-derived particles relevant for Sub-Saharan household environments. Particles (< 2.5 µm) were collected using a high-volume sampler during combustion of traditional Ethiopian biomass fuels: cow dung, eucalyptus wood and eucalyptus charcoal. Diesel exhaust particles (DEP, NIST 2975) served as reference particles. The highest levels of particle-bound polycyclic aromatic hydrocarbons (PAHs) were found in wood (3219 ng/mg), followed by dung (618 ng/mg), charcoal (136 ng/mg) and DEP (118 ng/mg) (GC-MS). BEAS-2B bronchial epithelial cells and THP-1 derived macrophages were exposed to particle suspensions (1-150 µg/mL) for 24 h. All particles induced concentration-dependent genotoxicity (comet assay) but no pro-inflammatory cytokine release in epithelial cells, whereas dung and wood particles also induced concentration-dependent cytotoxicity (Alamar Blue). Only wood particles induced concentration-dependent cytotoxicity and genotoxicity in macrophage-like cells, while dung particles were unique at increasing secretion of pro-inflammatory cytokines (IL-6, IL-8, TNF-α). In summary, particles derived from combustion of less energy dense fuels like dung and wood had a higher PAH content and were more cytotoxic in epithelial cells. In addition, the least energy dense and cheapest fuel, dung, also induced pro-inflammatory effects in macrophage-like cells. These findings highlight the influence of fuel type on the toxic profile of the emitted particles and warrant further research to understand and mitigate health effects of indoor air pollution.

"Air That Once Was Breath" Part 2: Wildfire Smoke and Airway Disease - "Climate Change, Allergy and Immunology" Special IAAI Article Collection: Collegium Internationale Allergologicum Update 2023

BACKGROUND

Population growth and climate change have led to more frequent and larger wildfires, increasing the exposure of individuals to wildfire smoke. Notably, asthma exacerbations and allergic airway sensitization are prominent outcomes of such exposure.

SUMMARY

Key research questions relate to determining the precise impact on individuals with asthma, including the severity, duration, and long-term consequences of exacerbations. Identifying specific risk factors contributing to vulnerability, such as age, genetics, comorbidities, or environmental factors, is crucial. Additionally, reliable biomarkers for predicting severe exacerbations need exploration. Understanding the long-term health effects of repeated wildfire smoke exposures in individuals with asthma and addressing healthcare disparities are important research areas.

KEY MESSAGES

This review discusses the need for comprehensive research efforts to better grasp wildfire smoke-induced respiratory health, particularly in vulnerable populations such as farmworkers, firefighters, pregnant women, children, the elderly, and marginalized communities. Effective mitigation would require addressing the current limitations we face by supporting research aimed at a better understanding of wildfire smoke-induced airway disease.

The impact of anthropogenic climate change on pediatric viral diseases

The adverse effects of climate change on human health are unfolding in real time. Environmental fragmentation is amplifying spillover of viruses from wildlife to humans. Increasing temperatures are expanding mosquito and tick habitats, introducing vector-borne viruses into immunologically susceptible populations. More frequent flooding is spreading water-borne viral pathogens, while prolonged droughts reduce regional capacity to prevent and respond to disease outbreaks with adequate water, sanitation, and hygiene resources. Worsening air quality and altered transmission seasons due to an increasingly volatile climate may exacerbate the impacts of respiratory viruses. Furthermore, both extreme weather events and long-term climate variation are causing the destruction of health systems and large-scale migrations, reshaping health care delivery in the face of an evolving global burden of viral disease. Because of their immunological immaturity, differences in physiology (e.g., size), dependence on caregivers, and behavioral traits, children are particularly vulnerable to climate change. This investigation into the unique pediatric viral threats posed by an increasingly inhospitable world elucidates potential avenues of targeted programming and uncovers future research questions to effect equitable, actionable change. IMPACT: A review of the effects of climate change on viral threats to pediatric health, including zoonotic, vector-borne, water-borne, and respiratory viruses, as well as distal threats related to climate-induced migration and health systems. A unique focus on viruses offers a more in-depth look at the effect of climate change on vector competence, viral particle survival, co-morbidities, and host behavior. An examination of children as a particularly vulnerable population provokes programming tailored to their unique set of vulnerabilities and encourages reflection on equitable climate adaptation frameworks.

Association of Exposure to Biomass Fuels with Occurrence of Chronic Obstructive Pulmonary Disease in Rural Western China: A Real-World Nested Case-Control Study

Background

This study investigated the potential contribution of biomass fuels exposure to the occurrence of chronic obstructive pulmonary disease (COPD) in rural areas of western China.

Methods

We analyzed data collected between October 2017 and October 2018 from a nested case-control study of individuals at least 40 years old in the general population in Mianyang City, Sichuan Province, China. Demographic information was collected using a custom-designed questionnaire, and lung function was measured using spirometry. We used multivariate logistic regression to explore the possible relationship between biomass fuels exposure and COPD, as well as between other potential risk factors and COPD. Bayes' theorem was used to estimate weights for different COPD risk factors.

Results

COPD was newly diagnosed in 500 of the 11398 adults surveyed, corresponding to an incidence of 4.39%. Individuals who were exposed to biomass fuels were at a significantly greater risk of developing COPD than those not exposed (OR 2.58, 95% CI 2.23-3.05). In subgroup analysis, exposure to biomass fuels increased the risk of COPD in men by 1.71 times (95% CI 1.09-2.68) and in women by 2.88 times (95% CI 2.01-3.48), in never-smokers by 2.18 times. Bayesian weights for COPD risk factors were highest for poor kitchen ventilation (W=31.13%) and biomass fuels exposure (W=18.08%).

Conclusion

Our data indicate that rural Chinese who are exposed to biomass fuels during cooking or heating are at greater risk of developing COPD. Efforts should be made to strengthen the construction of clean energy infrastructure, so as to reduce the use of biomass fuels and thereby help prevent COPD.

Chronic Obstructive Pulmonary Disease in Cameroon: Prevalence and Predictors-A Multisetting Community-Based Study

Objective

Little is known concerning chronic obstructive pulmonary disease (COPD) in Sub-Saharan Africa (SSA), where the disease remains underdiagnosed. We aimed to estimate its prevalence in Cameroon and look for its predictors.

Methods

Adults aged 19 years and older were randomly selected in 4 regions of Cameroon to participate in a cross-sectional community-based study. Data were collected in the participant's home or place of work. Spirometry was performed on selected participants. COPD was defined as the postbronchodilator forced expiratory volume in 1 second/forced vital capacity ratio (FEV1/FVC) < lower limit of normal, using the global lung initiative (GLI) equations for Black people. Binomial logistic regression was used to seek COPD-associated factors. The strength of the association was measured using the adjusted odds ratio (aOR).

Results

A total of 5055 participants (median age (25th-75th percentile) = 43 (30-56) years, 54.9% of women) were enrolled. COPD prevalence (95% confidence interval (95% CI)) was 2.9% (2.4, 3.3)%. Independent predictors of COPD (aOR (95% CI)) were a high educational level (4.7 (2.0, 11.1)), living in semiurban or rural locality (1.7 (1.4, 3.0)), tobacco smoking (1.7 (1.1, 2.5)), biomass fuel exposure (1.9 (1.1, 3.3)), experience of dyspnea (2.2 (1.4, 3.5)), history of tuberculosis (3.6 (1.9, 6.7)), and history of asthma (6.3 (3.4, 11.6)). Obesity was protective factor (aOR (95%CI) = 0.3 (0.2, 0.5)).

Conclusion

The prevalence of COPD was relatively low. Alternative risk factors such as biomass fuel exposure, history of tuberculosis, and asthma were confirmed as predictors.

Contribution of adaptive immunity to human COPD and experimental models of emphysema

The pathophysiology of chronic obstructive pulmonary disease (COPD) and the undisputed role of innate immune cells in this condition have dominated the field in the basic research arena for many years. Recently, however, compelling data suggesting that adaptive immune cells may also contribute to the progressive nature of lung destruction associated with COPD in smokers have gained considerable attention. The histopathological changes in the lungs of smokers can be limited to the large or small airways, but alveolar loss leading to emphysema, which occurs in some individuals, remains its most significant and irreversible outcome. Critically, however, the question of why emphysema progresses in a subset of former smokers remained a mystery for many years. The recognition of activated and organized tertiary T- and B-lymphoid aggregates in emphysematous lungs provided the first clue that adaptive immune cells may play a crucial role in COPD pathophysiology. Based on these findings from human translational studies, experimental animal models of emphysema were used to determine the mechanisms through which smoke exposure initiates and orchestrates adaptive autoreactive inflammation in the lungs. These models have revealed that T helper (Th)1 and Th17 subsets promote a positive feedback loop that activates innate immune cells, confirming their role in emphysema pathogenesis. Results from genetic studies and immune-based discoveries have further provided strong evidence for autoimmunity induction in smokers with emphysema. These new findings offer a novel opportunity to explore the mechanisms underlying the inflammatory landscape in the COPD lung and offer insights for development of precision-based treatment to halt lung destruction.

Overview of the Mechanisms of Oxidative Stress: Impact in Inflammation of the Airway Diseases

Inflammation of the human lung is mediated in response to different stimuli (e.g., physical, radioactive, infective, pro-allergenic or toxic) such as cigarette smoke and environmental pollutants. They often promote an increase in inflammatory activities in the airways that manifest themselves as chronic diseases (e.g., allergic airway diseases, asthma, chronic bronchitis/chronic obstructive pulmonary disease (COPD) or even lung cancer). Increased levels of oxidative stress (OS) reduce the antioxidant defenses, affect the autophagy/mitophagy processes, and the regulatory mechanisms of cell survival, promoting inflammation in the lung. In fact, OS potentiate the inflammatory activities in the lung, favoring the progression of chronic airway diseases. OS increases the production of reactive oxygen species (ROS), including superoxide anions (O₂^-), hydroxyl radicals (OH) and hydrogen peroxide (H₂O₂), by the transformation of oxygen through enzymatic and non-enzymatic reactions. In this manner, OS reduces endogenous antioxidant defenses in both nucleated and non-nucleated cells. The production of ROS in the lung can derive from both exogenous insults (cigarette smoke or environmental pollution) and endogenous sources such as cell injury and/or activated inflammatory and structural cells. In this review, we describe the most relevant knowledge concerning the functional interrelation between the mechanisms of OS and inflammation in airway diseases.

Therapeutic Potential of Small Molecules Targeting Oxidative Stress in the Treatment of Chronic Obstructive Pulmonary Disease (COPD): A Comprehensive Review

Chronic obstructive pulmonary disease (COPD) is an increasing and major global health problem. COPD is also the third leading cause of death worldwide. Oxidative stress (OS) takes place when various reactive species and free radicals swamp the availability of antioxidants. Reactive nitrogen species, reactive oxygen species (ROS), and their counterpart antioxidants are important for host defense and physiological signaling pathways, and the development and progression of inflammation. During the disturbance of their normal steady states, imbalances between antioxidants and oxidants might induce pathological mechanisms that can further result in many non-respiratory and respiratory diseases including COPD. ROS might be either endogenously produced in response to various infectious pathogens including fungi, viruses, or bacteria, or exogenously generated from several inhaled particulate or gaseous agents including some occupational dust, cigarette smoke (CS), and air pollutants. Therefore, targeting systemic and local OS with therapeutic agents such as small molecules that can increase endogenous antioxidants or regulate the redox/antioxidants system can be an effective approach in treating COPD. Various thiol-based antioxidants including fudosteine, erdosteine, carbocysteine, and N-acetyl-L-cysteine have the capacity to increase thiol content in the lungs. Many synthetic molecules including inhibitors/blockers of protein carbonylation and lipid peroxidation, catalytic antioxidants including superoxide dismutase mimetics, and spin trapping agents can effectively modulate CS-induced OS and its resulting cellular alterations. Several clinical and pre-clinical studies have demonstrated that these antioxidants have the capacity to decrease OS and affect the expressions of several pro-inflammatory genes and genes that are involved with redox and glutathione biosynthesis. In this article, we have summarized the role of OS in COPD pathogenesis. Furthermore, we have particularly focused on the therapeutic potential of numerous chemicals, particularly antioxidants in the treatment of COPD.

Development of a screening protocol to identify persons who are responsive to wood smoke particle-induced airway inflammation with pilot assessment of GSTM1 genotype and asthma status as response modifiers

BACKGROUND

We are currently screening human volunteers to determine their sputum polymorphonuclear neutrophil (PMN) response 6- and 24-hours following initiation of exposure to wood smoke particles (WSP). Inflammatory responders (≥10% increase in %PMN) are identified for their subsequent participation in mitigation studies against WSP-induced airways inflammation. In this report we compared responder status (<i>N</i> = 52) at both 6 and 24 hr time points to refine/expand its classification, assessed the impact of the GSTM1 genotype, asthma status and sex on responder status, and explored whether sputum soluble phase markers of inflammation correlate with PMN responsiveness to WSP.

RESULTS

Six-hour responders tended to be 24-hour responders and vice versa, but 24-hour responders also had significantly increased IL-1beta, IL-6, IL-8 at 24 hours post WSP exposure. The GSTM1 null genotype significantly (<i>p</i> &lt; 0.05) enhanced the %PMN response by 24% in the 24-hour responders and not at all in the 6 hours responders. Asthma status enhanced the 24 hour %PMN response in the 6- and 24-hour responders. In the entire cohort (not stratified by responder status), we found a significant, but very small decrease in FVC and systolic blood pressure immediately following WSP exposure and sputum %PMNs were significantly increased and associated with sputum inflammatory markers (IL-1beta, IL-6, IL-8, and PMN/mg) at 24 but not 6 hours post exposure. Blood endpoints in the entire cohort showed a significant increase in %PMN and PMN/mg at 6 but not 24 hours. Sex had no effect on %PMN response.

CONCLUSIONS

The 24-hour time point was more informative than the 6-hour time point in optimally and expansively defining airway inflammatory responsiveness to WSP exposure. GSTM1 and asthma status are significant effect modifiers of this response. These study design and subject parameters should be considered before enrolling volunteers for proof-of-concept WSP mitigation studies.

Air Quality in Africa: Public Health Implications

This review highlights the importance of air quality in the African urban development process. We address connections between air pollution and (a) rapid urbanization, (b) social problems, (c) health impacts, (d) climate change, (e) policies, and (f) new innovations. We acknowledge that air pollution levels in Africa can be extremely high and a serious health threat. The toxic content of the pollution could relate to region-specific sources such as low standards for vehicles and fuels, cooking with solid fuels, and burning household waste. We implore the pursuit of interdisciplinary research to create new approaches with relevant stakeholders. Moreover, successful air pollution research must regard conflicts, tensions, and synergies inherent to development processes in African municipalities, regions, and countries. This includes global relationships regarding climate change, trade, urban planning, and transportation. Incorporating aspects of local political situations (e.g., democracy) can also enhance greater political accountability and awareness about air pollution.

Climate Change and Global Issues in Allergy and Immunology

The steady increase in global temperatures, resulting from the combustion of fossil fuels and the accumulation of greenhouse gases (GHG), continues to destabilize all ecosystems worldwide. Although annual emissions must halve by 2030 and reach net-zero by 2050 to limit some of the most catastrophic impacts associated with a warming planet, the world's efforts to curb GHG emissions fall short of the commitments made in the 2015 Paris Agreement (1). To this effect, July 2021 was recently declared the hottest month ever recorded in 142 years (2). The ramifications of these changes on global temperatures are complex and further promote outdoor air pollution, pollen exposure, and extreme weather events. Besides worsening respiratory health, air pollution, promotes atopy and susceptibility to infections. The GHG effects on pollen affect the frequency and severity of asthma and allergic rhinitis. Changes in temperature, air pollution, and extreme weather events exert adverse multisystemic health effects and disproportionally affect disadvantaged and vulnerable populations. This article is an update for allergists and immunologists about the health impacts of climate change, already evident in our daily practices. It is also a call to action and advocacy, including integrating climate change-related mitigation, education, and adaptation measures to protect our patients and avert further injury to our planet.

The "Slow Horse Racing Effect" on Lung Function in Adult Life in Chronic Obstructive Pulmonary Disease Associated to Biomass Exposure

Although different trajectories in lung function decline have been identified in patients with COPD associated to tobacco exposure (TE-COPD), genetic, environmental, and infectious factors affecting lung function throughout life have not been fully elucidated in patients with COPD associated to biomass (BE-COPD). In this review, we present current epidemiological findings and notable advances in the natural history of lung decline in BE-COPD, as well as conditions modeling the FEV₁ trajectory, such as health insults, during the first years of childhood. Evidence shows that women exposed to biomass smoke reach adult life with a lower FEV₁ than expected. However, in contrast to the “horse racing effect” predicting an excessive lung-function decline in forthcoming years, as observed in smokers, this decline is slower in non-smokers, and no rapid decliners are observed. Accordingly, BE-COPD might be considered another phenotype of COPD based on assessments of lung function decline. Likewise, other functional and clinical aspects described in this review suggest that this condition might be similar to TE-COPD. More research is needed to fully characterize this subgroup of variants of COPD.

Fabricators and End-Users of Single-Pot Biomass Stoves: Conceptualizing, Hypothesis and Performance Metrics for Developing Energy Sustainability Framework

In this study, interviewer-based questionnaires of 67 variables were administered to local fabricators and end-users of single-pot biomass stoves (SPBS) in Ghana. Additionally, two randomly selected traditional and improved SPBS were lab-tested using standard performance metrics. From the study, the relationship between fabricators and end-users was conceptualized based on selected indicators and assumptions. The study results indicated that the primary design resources for fabrication were patterns and templates, and that major challenges to fabrication were lack of training in design principles, standards and safety, poor emission efficiency and financial sustainability. Whereas end-users of improved SPBS were less affected by heat and smoke, end-users of traditional SPBS were mostly affected. From hypothesis test, because the calculated χ2cal = 24.05, and is greater than the tabulated χ2crit = 3.841, it is concluded that there is a relationship between heat, smoke effect and gender, and that female end-users of traditional SPBS were particularly affected during cooking. The traditional SPBS emitted more CO2 and CO than improved SPBS. Comparatively, 38% more end-users of traditional SPBS observed charcoal ash residue in the cooking area than improved SPBS users. Four basic practices of managing ashes from SPBS are developed. Finally, a fabricator and end-user framework are developed for energy sustainability and quality improvement.

Association between household air pollution and child mortality in Myanmar using a multilevel mixed-effects Poisson regression with robust variance

Household air pollution (HAP) from solid fuel use (SFU) for cooking is a major public health threat for women and children in low and middle-income countries. This study investigated the associations between HAP and neonatal, infant, and under-five child mortality in Myanmar. The study consisted of 3249 sample of under-five children in the households from the first Myanmar Demographic and Health Survey 2016. Fuel types and levels of exposure to SFU (no, moderate and high) were proxies for HAP. We estimated covariate-adjusted relative risks (aRR) of neonatal, infant, and under-five child mortality with 95% confidence intervals, accounting for the survey design. The prevalence of SFU was 79.0%. The neonatal, infant, and under-five child mortality rates were 26, 45, and 49 per 1000 live births, respectively. The risks of infant (aRR 2.02; 95% CI 1.01-4.05; p-value = 0.048) and under-five mortality (aRR 2.16; 95% CI 1.07-4.36; p-value = 0.031), but not neonatal mortality, were higher among children from households with SFU compared to children from households using clean fuel. Likewise, children highly exposed to HAP had higher risks of mortality than unexposed children. HAP increases the risks of infant and under-five child mortality in Myanmar, which could be reduced by increasing access to clean cookstoves and fuels.

Effect of Indoor Air Pollution on Chronic Obstructive Pulmonary Disease (COPD) Deaths in Southern Asia-A Systematic Review and Meta-Analysis

BACKGROUND

About half of the population in developing countries are exposed to indoor pollution such as combustion fuels at present. Chronic obstructive pulmonary disease (COPD) is one of the leading causes of mortality globally and the primary cause of COPD in women is indoor air pollution exposure, while tobacco smoking is the leading cause in men. The aim of this systematic review and meta-analysis is to evaluate the correlation between the indoor air pollution and deaths related to COPD and COPD prevalence in South Asia.

METHODS

A systematic search on studies with sufficient statistical power has been conducted from 1985 until 30 June 2020, in English electronic databases following Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines in MEDLINE and PubMed databases with the terms Chronic Obstructive Pulmonary disease COPD or Chronic Bronchitis or Emphysema or COPD Deaths or Chronic Obstructive Lung Disease or Airflow Obstruction or Chronic Airflow Obstruction or Airflow Obstruction, Chronic or Bronchitis, Chronic and Mortality or Death or Deceased was conducted. Studies were eligible if they were Prospective controlled or non-controlled trials conducted in Southern Asia/ Asia and Retrospective studies conducted in Southern Asia/ Asia.

RESULTS

The results have concluded that long term exposure to indoor pollution had a significant effect on COPD deaths as well as its symptoms. Odd's ratio was in a range of 1.05 (Randomized controlled trials) to 7.87 (Cross sectional studies) for all the studies mentioned. Meta-analysis observed a significantly higher Odds Ratio of 2.13 for COPD mortality and 2.08 for COPD prevalence on exposure to indoor air pollution.

CONCLUSION

Exposure to solid fuel smoke is consistently and significantly correlated with COPD mortality and COPD prevalence in South Asian countries, in spite of heterogeneity observed in the studies included. For performing domestic tasks, initiatives are to be taken to reduce dependency on solid fuel by using cleaner alternatives or comparatively cleaner technology.

Oxidative Stress-Derived Mitochondrial Dysfunction in Chronic Obstructive Pulmonary Disease: A Concise Review

Chronic obstructive pulmonary disease (COPD) is a progressive and disabling disorder marked by airflow limitation and extensive destruction of lung parenchyma. Cigarette smoke is the major risk factor for COPD development and has been associated with increased oxidant burden on multiple cell types in the lungs. Elevated levels of reactive oxygen species (ROS) may significantly affect expression of biological molecules, signaling pathways, and function of antioxidant defenses. Although inflammatory cells, such as neutrophils and macrophages, contribute to the release of large quantities of ROS, mitochondrial dysfunction plays a critical role in ROS production due to oxidative phosphorylation. Although mitochondria are dynamic organelles, excess oxidative stress is able to alter mitochondrial function, morphology, and RNA and protein content. Indeed, mitochondria may change their shape by undergoing fusion (regulated by mitofusin 1, mitofusin 2, and optic atrophy 1 proteins) and fission (regulated by dynamin-related protein 1), which are essential processes to maintain a healthy and functional mitochondrial network. Cigarette smoke can induce mitochondrial hyperfusion, thus reducing mitochondrial quality control and cellular stress resistance. Furthermore, diminished levels of enzymes involved in the mitophagy process, such as Parkin (a ubiquitin ligase E3) and the PTEN-induced putative kinase 1 (PINK1), are commonly observed in COPD and correlate directly with faulty removal of dysfunctional mitochondria and consequent cell senescence in this disorder. In this review, we highlight the main mechanisms for the regulation of mitochondrial quality and how they are affected by oxidative stress during COPD development and progression.

Coenzyme Q10 in COPD: An Unexplored Opportunity?

COPD represents a major cause of mortality and morbidity worldwide, is linked to systemic inflammation and tends to coexist with a variety of comorbidities. Inflammation, oxidative stress and protease-antiprotease imbalance represent the pathogenic triad of COPD. Even though oxidative stress and mitochondrial dysfunction is a well-studied phenomenon in COPD and there is a variety of studies that aim to counteract its effect, there is limited data available on the use of coenzyme Q10 in COPD. The aim of the current review is to analyze the current data on the use of coenzyme Q10 in the management of COPD and frequently encountered comorbidities.

Prevalence and risk factors of asthma among school going children in urban area of North India

Introduction

Bronchial asthma is a chronic respiratory illness of global importance. Recent reports depict the increasing prevalence of this disorder in urban areas.

Methods

An observational study was designed with a sample size of 1163 children from grade 4 to grade 12, involving 8 randomly selected schools in 2015-2016. Modified International Study of Asthma and Allergy in Childhood [ISAAC] questionnaire in local language [Hindi version] was used for data collection. The data of assessed risk factors were collected and analysed.

Results

Prevalence of asthma in the studied population was 2.8%. Multivariate analysis revealed a significant association of risk of asthma with use of firewood kitchener for cooking, keeping pet animals at home, high body mass index (BMI), absence of ventilator measures like chimney and aero-vent. Logistic regression analysis revealed use of firewood kitchener for cooking (odds ratio (OR) = 4.9, 95% confidence interval (CI) = 2.93-11.3), absence of smoke outlet (OR 2.8, 95% CI 1.3-5.8) and keeping pet animals (OR 3.2, CI 1.6-6.8) at home were observed to be significantly associated with asthma.

Conclusion

Prevalence of asthma in our cohort was significantly lesser than that of developed world. Household smoke was the most conspicuous risk factor contributory to childhood asthma in this part of world.

Asthma and allergic rhinitis among young parents in China in relation to outdoor air pollution, climate and home environment

We estimated associations between ambient air pollution, home environment and asthma as well as rhinitis among adults across China. A total of 40,279 young adults from eight Chinese cities participated in a questionnaire survey (participation rate 75%). There were questions on health and home environment. Information on city level gross domestic product (GDP) per capita, ambient temperature and PM₁₀ and NO₂ were collected from registers. Two-level logistic regression models were used to study health associations. Totally 1.6% reported asthma and 6.6% reported allergic rhinitis (AR). Higher temperature was associated with more asthma but less AR. Higher GDP was associated with less asthma but more AR. Higher degree of urbanization, higher level of NO₂ and living near heavily trafficked road were risk factors for asthma and AR. Participants in older buildings reported more asthma. Redecoration and buying new furniture were related to more asthma and AR (OR = 1.15-1.91). Using natural gas (OR = 1.34) and biomass (OR = 1.35) for cooking were risk factors for AR. Burning mosquito coils and incense increased the risk of asthma and AR. Cat keeping (OR = 2.88), dog keeping (OR = 2.04), cockroaches (OR = 1.54) and rats or mice (OR = 1.46) were associated with asthma. Cockroaches increased the risk of AR (OR = 1.22). Air humidifier and air cleaner were linked to asthma and AR. Frequent cleaning and exposing bedding to sunshine were protective. In conclusion, urbanization, NO₂ and traffic exhaust can increase the risk of adult asthma and AR. Higher ambient temperature was related to more asthma but less AR. Indoor animals such as cats, dogs, rats/mice and presence of cockroaches were associated with asthma or AR. Indoor chemical sources such as redecoration and new furniture were other risk factors. Cooking with natural gas or biomass and burning mosquito coils and incense were associated with asthma or AR. Frequent cleaning and exposing bedding to sunshine were protective.

Enfermedad pulmonar obstructiva crónica (EPOC) Bases para el médico general

Chronic obstructive pulmonary disease (COPD) is a chronic degenerative disease. It is a frequent, preventable and treatable disease characterized by persistent respiratory symptoms and airflow limitation. The National Institute of Respiratory Diseases (INER), ranked COPD in 2016 in fourth place in the table of annual morbidity and mortality in Mexico. The prevalence of COPD is directly related to smoking; however, its development is multifactorial. For its study it is important to know of any prior exposure to risk factors and of any manifestation of the main symptoms. To make a diagnosis, a detailed clinical history, where the largest amount of data is collected from every new possible COPD patient, and a spirometry are essential. Individual pharmacological treatment is necessary due to the great variability among COPD patients. The drugs used in the treatment of COPD reduce the symptoms, the frequency and severity of exacerbations; however, there is no medication that modifies the long-term deterioration of the lung function. Therefore, a basic knowledge of this condition by the medical doctor first contacted, is essential for the suspicion of COPD in its initial stage and thus, offer the patient immediate medical intervention. The objective of the present work is to provide a basic overview of COPD to the general practitioner. Key words:Chronic obstructive pulmonary disease; biomass; tobacco; chronic obstructive bronchitis; emphysema; respiratory system

Single Nucleotide and Copy-Number Variants in IL4 and IL13 Are Not Associated with Asthma Susceptibility or Inflammatory Markers: A Case-Control Study in a Mexican-Mestizo Population

BACKGROUND

Asthma is a complex and chronic inflammatory airway disease. Asthma's etiology is unknown; however, genetic and environmental factors could affect disease susceptibility. We designed a case-control study aimed to evaluate the role of single-nucleotide polymorphisms (SNP), and copy-number variants (CNV) in the IL4 and IL13 genes in asthma susceptibility and their participation in plasma cytokine levels depending on genotypes Methods: We include 486 subjects, divided into asthma patients (AP, n = 141) and clinically healthy subjects (CHS, n = 345). We genotyped three SNP, two in the IL4 and two in the IL13 gene; also, two CNVs in IL4. The IL-4, IL-13 and IgE plasma levels were quantified.

RESULTS

Biomass-burning smoke exposure was higher in the AP group compared to CHS (47.5% vs. 20.9%; p < 0.01, OR = 3.4). No statistical differences were found in the genetic association analysis. In both CNV, we only found the common allele. For the analysis of IL-4, IL-13, and IgE measures stratified by genotypes, no significant association or correlation was found.

CONCLUSION

In the Mexican-mestizo population, SNPs neither CNVs in IL4 nor IL13 are associated with asthma susceptibility or involved serum cytokine levels. Biomass-burning smoke is a risk factor in asthma susceptibility.

Lung injury caused by exposure to the gaseous fraction of exhaust from biomass combustion (cashew nut shells): a mice model

Currently, to reduce the use of nonrenewable energy sources in energy matrices, some industries have already incorporated biomass as a source of energy for their processes. Additionally, filters are used in an attempt to retain the particulate matter present in exhaust gases. In this work, the emission gases of a cashew nut shell (CNS) combustion reactor and the deleterious effects on the respiratory system of mice exposed to gaseous fraction present in CNS emissions (GF-CNS) are analyzed. The system for CNS combustion is composed of a cylindrical stainless steel burner, and exhaust gases generated by CNS combustion were directed through a chimney to a system containing two glass fiber filters to retain all the PM present in the CNS exhaust and, posteriorly, were directed to a mice exposure chamber. The results show changes in the variables of respiratory system mechanics (G, H, C_ST, IC, and PV loop area) in oxidative stress (SOD, CAT, and NO₂^-), as well as in the histopathological analysis and lung morphometry (alveolar collapse, PMN cells, mean alveolar diameter, and BCI). Through our results, it has been demonstrated that even with the use of filters by industries for particulate material retention, special attention should still be given to the gaseous fraction that is released into the environment.

Wood stove interventions and child respiratory infections in rural communities: KidsAir rationale and methods

BACKGROUND

Acute lower respiratory tract infections (LRTIs) account for >27% of all hospitalizations among US children under five years of age. Residential burning of biomass for heat leads to elevated indoor levels of fine particulate matter (PM2.5) that often exceed current health based air quality standards. This is concerning as PM2.5 exposure is associated with many adverse health outcomes, including a greater than three-fold increased risk of LRTIs. Evidence-based efforts are warranted in rural and American Indian/Alaska Native (AI/AN) communities in the US that suffer from elevated rates of childhood LRTI and commonly use wood for residential heating.

DESIGN

In three rural and underserved settings, we conducted a three-arm randomized controlled, post-only intervention trial in wood stove homes with children less than five years old. Education and household training on best-burn practices were introduced as one intervention arm (Tx1). This intervention was evaluated against an indoor air filtration unit arm (Tx2), as well as a control arm (Tx3). The primary outcome was LRTI incidence among children under five years of age.

DISCUSSION

To date, exposure reduction strategies in wood stove homes have been either inconsistently effective or include factors that limit widespread dissemination and continued compliance in rural and economically disadvantaged populations. As part of the "KidsAIR" study described herein, the overall hypothesis was that a low-cost, educational intervention targeting indoor wood smoke PM2.5 exposures would be a sustainable approach for reducing children's risk of LRTI in rural and AI/AN communities.

Pediatric Asthma: A Global Epidemic

The global prevalence, morbidity and mortality related to childhood asthma among children has increased significantly over the last 40 years. Although asthma is recognized as the most common chronic disease in children, issues of underdiagnosis and undertreatment persist. There are substantial global variations in the prevalence of asthma symptoms in children, with up to 13-fold differences between countries. The rising number of hospital admissions for asthma may reflect an increase in asthma severity, poor disease management and/or the effect of poverty. The financial burden of asthma is relatively high within developed countries (those for which data is available) spending 1 to 2% of their healthcare budget on this condition. Established in 1989, the Global Initiative for Asthma (GINA) attempts to raise awareness about the increasing prevalence of asthma, improve management and reduce the burden of asthma worldwide. Despite global efforts, GINA has not achieved its goal, even among developed nations. There are multiple barriers to reducing the global burden of asthma, including limited access to care and/or medications, and lack of prioritization as a public healthcare priority. In addition, the diversity of healthcare systems worldwide and large differences in access to care require that asthma management guidelines be tailored to local needs.

Health risk assessment due to biomass smoke exposure in Indian indoor environment: An empirical approach using lung deposition model

The paper subsumes a framework that assesses health risk due to exposure to different fuel combustion through articulation of modern microscopic techniques, empirical equations, lung diagnostic tools and a pre-existing model that has been extrapolated to futuristic aspects (within controlled conditions). The framework was tested on 132 household cooks belonging to different age groups and using different types of fuel. The inhalable fraction released during fuel combustion varied in morphological characteristics and deposition site. Micrographs obtained using Scanning Electron Microscope (SEM) analysis of (biomass smoke) soot indicates aggregate formation attributing to a higher level of health risk. Further, abnormal ventilatory function along with higher risk (RR > 1) was more evident within biomass fuel users. The condition further exacerbates while using dung cakes due to high levels of emissions (294.3 particles/liter) that deposit in the upper respiratory tract (0.0899). Further, the population attributable risk percent (79%) calculated on the basis of cooking behavior suggests a 'rural culture' health determinant as clean fuel usage is not practiced as an outcome of low literacy and poor income in the region. These preliminary findings highlight the drudgery of impuissant women who are exposed to high particulate emissions on a regular basis which results in reduced lung function. Nevertheless, further cogitation is required to eliminate the limitations in this study and explore further linkages between exposure and vulnerable group to generate meaningful policy recommendations.

The burden of chronic respiratory diseases and their heterogeneity across the states of India: the Global Burden of Disease Study 1990-2016

BACKGROUND

India has 18% of the global population and an increasing burden of chronic respiratory diseases. However, a systematic understanding of the distribution of chronic respiratory diseases and their trends over time is not readily available for all of the states of India. Our aim was to report the trends in the burden of chronic respiratory diseases and the heterogeneity in their distribution in all states of India between 1990 and 2016.

METHODS

Using all accessible data from multiple sources, we estimated the prevalence of major chronic respiratory diseases and the deaths and disability-adjusted life-years (DALYs) caused by them for every state of India from 1990 to 2016 as part of the Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2016. We assessed heterogeneity in the burden of chronic obstructive pulmonary disease (COPD) and asthma across the states of India. The states were categorised into four groups based on their epidemiological transition level (ETL). ETL was defined as the ratio of DALYs from communicable diseases to those from non-communicable diseases and injuries combined, with a low ratio denoting high ETL and vice versa. We also assessed the contribution of risk factors to DALYs due to COPD. We compared the burden of chronic respiratory diseases in India against the global average in GBD 2016. We calculated 95% uncertainty intervals (UIs) for the point estimates.

FINDINGS

The contribution of chronic respiratory diseases to the total DALYs in India increased from 4·5% (95% UI 4·0-4·9) in 1990 to 6·4% (5·8-7·0) in 2016. Of the total global DALYs due to chronic respiratory diseases in 2016, 32·0% occurred in India. COPD and asthma were responsible for 75·6% and 20·0% of the chronic respiratory disease DALYs, respectively, in India in 2016. The number of cases of COPD in India increased from 28·1 million (27·0-29·2) in 1990 to 55·3 million (53·1-57·6) in 2016, an increase in prevalence from 3·3% (3·1-3·4) to 4·2% (4·0-4·4). The age-standardised COPD prevalence and DALY rates in 2016 were highest in the less developed low ETL state group. There were 37·9 million (35·7-40·2) cases of asthma in India in 2016, with similar prevalence in the four ETL state groups, but the highest DALY rate was in the low ETL state group. The highest DALY rates for both COPD and asthma in 2016 were in the low ETL states of Rajasthan and Uttar Pradesh. The DALYs per case of COPD and asthma were 1·7 and 2·4 times higher in India than the global average in 2016, respectively; most states had higher rates compared with other locations worldwide at similar levels of Socio-demographic Index. Of the DALYs due to COPD in India in 2016, 53·7% (43·1-65·0) were attributable to air pollution, 25·4% (19·5-31·7) to tobacco use, and 16·5% (14·1-19·2) to occupational risks, making these the leading risk factors for COPD.

INTERPRETATION

India has a disproportionately high burden of chronic respiratory diseases. The increasing contribution of these diseases to the overall disease burden across India and the high rate of health loss from them, especially in the less developed low ETL states, highlights the need for focused policy interventions to address this significant cause of disease burden in India.

FUNDING

Bill & Melinda Gates Foundation; and Indian Council of Medical Research, Department of Health Research, Ministry of Health and Family Welfare, Government of India.

Association of Elevated Serum GM-CSF, IFN-γ, IL-4, and TNF-α Concentration with Tobacco Smoke Induced Chronic Obstructive Pulmonary Disease in a South Indian Population

Background

Chronic obstructive pulmonary disease (COPD) is a devastating condition with limited pharmacotherapeutic options and exceptionally high public-health burden globally as well as in India. Tobacco smoking is the primary cause for COPD among men in India. Systemic inflammation involving altered regulation of cytokines controlling the host defense mechanism is a hallmark of COPD pathogenesis. However, biomarker discovery studies are limited among Indian COPD patients.

Methods

We assessed the serum concentrations [median (25th-75th percentile) pg/ml] of interleukin (IL)-2,4,6,8,10, granulocyte macrophage colony stimulating factor (GM-CSF), interferon gamma (IFN-γ), and tumor necrosis factor alpha (TNF-α) using a multiplexed immunoassay. Our study cohort consisted of 30 tobacco smokers with COPD (TS COPD) and 20 tobacco smokers without COPD (TS CONTROL) from South India. The study population was matched for age, sex (male), and tobacco consumption (pack-years). COPD was diagnosed according to the global initiative for chronic obstructive lung disease (GOLD) criteria of persistent airflow obstruction determined by the ratio of postbronchodilator forced expiratory volume in 1 second/forced vital capacity (FEV₁/FVC) of <0.7. A validated structured questionnaire-based survey [Burden of Obstructive Lung Disease (BOLD) study] and spirometry were performed during house to house visit of the field study. Statistical analysis included nonparametric (two-tailed) Mann-Whitney U and Spearman rank test, as appropriate (significance: p<0.05).

Results

Serum GM-CSF [69.64 (46.67, 97.48); 36.78 (30.07, 53.88), p=0.014], IFN-γ [51.06 (17.00, 84.86); 11.70 (3.18, 32.81), p=0.017], IL-4 [9.09 (1.8, 19.9); 1.8 (1.8, 4.46); p=0.024], and TNF-α [20.68 (5.5, 29.26); 3.5 (3.5, 4.5); p<0.001] concentrations (pg/ml) were increased in TS COPD subjects compared to TS CONTROL. A weak correlation between lung function parameters and cytokine concentrations was detected.

Conclusion

Our pilot study reveals GM-CSF, IFN-γ, IL-4, and TNF-α as plausible COPD susceptibility biomarkers within the investigated South Indian population that needs to be validated in a larger cohort.

Prevalence and determinants of airflow limitation in urban and rural children exposed to cooking fuels in South-East Nigeria

Background Biofuels and other cooking fuels are used in households in low- and middle-income countries. Aim To investigate the impact of cooking fuels on lung function in children in urban and rural households in South-East Nigeria. Methods The multi-stage sampling method was used to enroll children exposed to cooking fuel in the communities. Lung function values FEV1, FVC and the FEV1/FVC ratio, were measured with ndd EasyOne^R spirometer. Airflow limitation was determined with FEV1/FVC Z-score values at -1.64 as the lower limit of normal (LLN5). The Global Lung Function Initiative 2012 software was used to calculate the lung function indices. Results The median age (range) of the 912 children enrolled was 10.6 years (6-18). Altogether, 468 (51.6%) children lived in rural areas. Seven hundred and thirty-seven (80.7%) were directly exposed to cooking fuels (418/737, 56.5% in rural areas). Wood and kerosene were the dominant fuels in rural and urban households. The respective mean Z-scores of the exposed children in rural and urban were zFEV1 -0.62, FVC -0.21, FEV1/FVC -0.83 and zFEV1 -0.57, zFVC -0.14, FEV1/FVC -0.75. Few (5.2%, 38/737) of the children had airflow limitation. Most of them (60.5%, 25/38) lived in the rural community; the lowest FEV1/FVC Z-scores were those of exposed to a combination of fuels. Conclusion Exposure to cooking fuels affects lung function in children with airway limitation in a small proportion, Control measures are advocated to reduce the morbidity related to cooking fuels exposure.

Sources and levels of particulate matter in North African and Sub-Saharan cities: a literature review

In order to assess the significance of PM in ambient air, it is necessary to evaluate their physical and chemical characteristics as well as identify their major emission sources. On a global scale, particulate matter in the atmosphere arises mainly from the combustion process of motorized vehicles, but natural sources are still considered as the major contributors. In Africa, PM emissions differ from those in developed countries; human activities such as biomass burning in households, poor household waste management, and the high number of diesel-powered vehicles are the predominant anthropogenic sources. Natural contributions are also observed. Saharan dust and savanna fires are the most common atmospheric natural sources of particulate matter. The present literature review gives an overview of the status of air quality in African cities and highlights the various sources of particulate matter emissions and local human activities specific to each African region. This could likely serve as a reference to evaluate the current air quality in this region and will be a useful tool in the future to develop pollution mitigation strategies at the source. Recommendations are proposed in the conclusion in order to reduce emissions from their sources, taking into account the low-income African countries.

Indoor air quality of low and middle income urban households in Durban, South Africa

INTRODUCTION

Elevated levels of indoor air pollutants may cause cardiopulmonary disease such as lower respiratory infection, chronic obstructive lung disease and lung cancer, but the association with tuberculosis (TB) is unclear. So far the risk estimates of TB infection or/and disease due to indoor air pollution (IAP) exposure are based on self-reported exposures rather than direct measurements of IAP, and these exposures have not been validated.

OBJECTIVE

The aim of this paper was to characterize and develop predictive models for concentrations of three air pollutants (PM₁₀, NO₂ and SO₂) in homes of children participating in a childhood TB study.

METHODS

Children younger than 15 years living within the eThekwini Municipality in South Africa were recruited for a childhood TB case control study. The homes of these children (n=246) were assessed using a walkthrough checklist, and in 114 of them monitoring of three indoor pollutants was also performed (sampling period: 24h for PM₁₀, and 2-3 weeks for NO₂ and SO₂). Linear regression models were used to predict PM₁₀ and NO₂ concentrations from household characteristics, and these models were validated using leave out one cross validation (LOOCV). SO₂ concentrations were not modeled as concentrations were very low.

RESULTS

Mean indoor concentrations of PM₁₀ (n=105)_, NO₂ (n=82) and SO₂ (n=82) were 64μg/m³ (range 6.6-241); 19μg/m³ (range 4.5-55) and 0.6μg/m³ (range 0.005-3.4) respectively with the distributions for all three pollutants being skewed to the right. Spearman correlations showed weak positive correlations between the three pollutants. The largest contributors to the PM₁₀ predictive model were type of housing structure (formal or informal), number of smokers in the household, and type of primary fuel used in the household. The NO₂ predictive model was influenced mostly by the primary fuel type and by distance from the major roadway. The coefficients of determination (R²) for the models were 0.41 for PM₁₀ and 0.31 for NO₂. Spearman correlations were significant between measured vs. predicted PM₁₀ and NO₂ with coefficients of 0.66 and 0.55 respectively.

CONCLUSION

Indoor PM₁₀ levels were relatively high in these households. Both PM₁₀ and NO₂ can be modeled with a reasonable validity and these predictive models can decrease the necessary number of direct measurements that are expensive and time consuming.

[Respiratory symptoms and obstructive ventilatory disorder in Tunisian woman exposed to biomass]

INTRODUCTION

In some Tunisian cities, especially semi-urbanized, the exposure to the smoke produced during combustion of the biomass, main source of pollution of indoor air, remains prevalent among non-smoking women.

AIM

To assess the relationship between exposure to biomass smoke and the presence of obstructive ventilatory disorder in the non-smoking women in semi-urban areas of Tunisia.

METHODS

Cross etiological study, using a questionnaire, including 140 non-smoking women responsible for cooking and/or exposed during heating by traditional means with objective measurement of their respiratory functions.

RESULTS

We found 81 women exposed to biomass for a period > or equal to 20 hours-years and 59 unexposed women. Exposed women reported more respiratory symptoms namely exertional dyspnea and/or chronic cough than unexposed. Of the 140 women, 14 women have an FEV/FEV6 <70 % of which 13 are exposed to biomass. We found a correlation between respiratory symptoms and obstructive ventilatory disorder in exposed women.

CONCLUSION

The air pollution inside the home during the traditional activities of cooking and/or heating is a respiratory risk factor for non-smoking women over the age of 30 years. Exposure to biomass smoke can cause chronic respiratory symptoms and persistent obstructive ventilatory disorder that can be consistent with COPD.

[Respiratory symptoms and obstructive ventilatory disorder in Tunisian woman exposed to biomass]

INTRODUCTION

In some Tunisian cities, especially semi-urbanized, the exposure to the smoke produced during combustion of the biomass, main source of pollution of indoor air, remains prevalent among non-smoking women.

AIM

To assess the relationship between exposure to biomass smoke and the presence of obstructive ventilatory disorder in the non-smoking women in semi-urban areas of Tunisia.

METHODS

Cross etiological study, using a questionnaire, including 140 non-smoking women responsible for cooking and/or exposed during heating by traditional means with objective measurement of their respiratory functions.

RESULTS

We found 81 women exposed to biomass for a period of≥20 hours-years and 59 unexposed women. Exposed women reported more respiratory symptoms namely exertional dyspnea and/or chronic cough than unexposed. Of the 140 women, 14 women have an FEV/FEV6<70% of which 13 are exposed to biomass. We found a correlation between respiratory symptoms and obstructive ventilatory disorder in exposed women.

CONCLUSION

The air pollution inside the home during the traditional activities of cooking and/or heating is a respiratory risk factor for non-smoking women over the age of 30 years. Exposure to biomass smoke can cause chronic respiratory symptoms and persistent obstructive ventilatory disorder that can consistent with COPD.

Rolling Tobacco in Banana Leaves, Newspaper, or Copybook Paper Associated With Significant Reduction in Lung Function in Vanuatu

In addition to the widespread availability of packaged cigarettes, the inhabitants of island nations of the Southwest Pacific frequently smoke commercially available loose tobacco using manufactured rolling papers, as well as locally grown tobacco rolled in manufactured rolling paper or wrapped in leaves, copybook paper, and newspaper. In this study, Vanuatu men who smoked local tobacco rolled in leaves, copybook paper, or newspaper showed significantly lower forced vital capacity (FVC), forced expiratory volume in 1 second (FEV1), and FEV1/FVC ratios than men who smoked packaged cigarettes, store-bought tobacco rolled in manufactured rolling paper, or who smoked locally grown tobacco rolled in manufactured rolling papers. The addition of toxins from these unusual tobacco-wrapping media produces lung function deficits similar to the pattern noted among tobacco smokers who also inhale smoke from burning biomass. Thus, public health initiatives should consider including strategies addressing the use of wrapping media among smokers in South Pacific island societies.

Estimation of local and external contributions of biomass burning to PM2.5 in an industrial zone included in a large urban settlement

A total of 85 PM_2.5 samples were collected at a site located in a large industrial zone (Porto Marghera, Venice, Italy) during a 1-year-long sampling campaign. Samples were analyzed to determine water-soluble inorganic ions, elemental and organic carbon, and levoglucosan, and results were processed to investigate the seasonal patterns, the relationship between the analyzed species, and the most probable sources by using a set of tools, including (i) conditional probability function (CPF), (ii) conditional bivariate probability function (CBPF), (iii) concentration weighted trajectory (CWT), and (iv) potential source contribution function (PSCF) analyses. Furthermore, the importance of biomass combustions to PM_2.5 was also estimated. Average PM_2.5 concentrations ranged between 54 and 16 μg m^-3 in the cold and warm period, respectively. The mean value of total ions was 11 μg m^-3 (range 1-46 μg m^-3): The most abundant ion was nitrate with a share of 44 % followed by sulfate (29 %), ammonium (14 %), potassium (4 %), and chloride (4 %). Levoglucosan accounted for 1.2 % of the PM_2.5 mass, and its concentration ranged from few ng m^-3 in warm periods to 2.66 μg m^-3 during winter. Average concentrations of levoglucosan during the cold period were higher than those found in other European urban sites. This result may indicate a great influence of biomass combustions on particulate matter pollution. Elemental and organic carbon (EC, OC) showed similar behavior, with the highest contributions during cold periods and lower during summer. The ratios between biomass burning indicators (K⁺, Cl^-, NO₃^-, SO₄^2-, levoglucosan, EC, and OC) were used as proxy for the biomass burning estimation, and the contribution to the OC and PM_2.5 was also calculated by using the levoglucosan (LG)/OC and LG/PM_2.5 ratios and was estimated to be 29 and 18 %, respectively.

Hydroxylated polycyclic aromatic hydrocarbons as biomarkers of exposure to wood smoke in wildland firefighters

Wildland firefighter's exposure to wildland fire or vegetative biomass smoke has mostly been assessed by personal monitoring to airborne pollutants. However, the use of biomarkers may accurately reflect the internal (systemic) dose received by the firefighter. In this study, we assessed occupational exposure to wildland fire smoke in 14 wildland firefighters working at prescribed burns at the Savannah River Site, South Carolina by measuring the urinary concentrations of nine hydroxylated metabolites of polycyclic aromatic hydrocarbons (OH-PAHs). Except for 1-hydroxynaphthalene, preshift median concentrations of the OH-PAHs were higher compared with the median concentrations reported among the US general population, indicating elevated exposures to PAHs among the wildland firefighters during the prescribed burn season. The postshift concentrations of OH-PAHs were 83-323% (P<0.0001) higher compared with the preshift concentrations. Higher postshift concentrations of individual OH-PAHs were observed in 49 (87.5%) to 53 (94.6%) of all the 56 pre-post sample pairs. Additionally, the cross-shift (pre- to postshift) increase in 4-hydroxy-phenanthrene urinary concentration was marginally associated (P<0.1) with work shift exposure to PM_2.5 and significantly associated (P<0.05) with levoglucosan, which is a marker of wildland fire or vegetative biomass smoke. These results suggest that OH-PAHs, especially 4PHE, may be useful biomarkers of wildland fire smoke exposure.

Occupational chronic obstructive pulmonary disease: a standard of care

BACKGROUND

Consistent evidence from population studies report that 10-15% of the total burden of chronic obstructive pulmonary disease (COPD) is associated with workplace exposures. This proportion of COPD could be eliminated if harmful workplace exposures were controlled adequately.

AIMS

To produce a standard of care for clinicians, occupational health professionals, employers and employees on the identification and management of occupational COPD.

METHODS

A systematic literature review was used to identify published data on the prevention, identification and management of occupational COPD. Scottish Intercollegiate Guidance Network grading and the Royal College of General Practitioner three star grading system were used to grade the evidence.

RESULTS

There are a number of specific workplace exposures that are established causes of COPD. Taking an occupational history in patients or workers with possible or established COPD will identify these. Reduction in exposure to vapours, gases, dusts and fumes at work is likely to be the most effective method for reducing occupational COPD. Identification of workers with rapidly declining lung function, irrespective of their specific exposure, is important. Individuals can be identified at work by accurate annual measures of lung function.

CONCLUSIONS

Early identification of cases with COPD is important so that causality can be considered and action taken to reduce causative exposures thereby preventing further harm to the individual and other workers who may be similarly exposed. This can be achieved using a combination of a respiratory questionnaire, accurate lung function measurements and control of exposures in the workplace.

Impulse oscillometry: The state-of-art for lung function testing

Impulse oscillometry (IOS) is a variant of forced oscillation technique, described by Dubois over 50 years ago, which permits passive measurement of lung mechanics. In this method, sound waves are superimposed on normal tidal breathing, and the disturbances in flow and pressure caused by the external waves are used to calculate parameters describing the resistance to airflow and reactive parameters that mostly relate to efficient storage and return of energy by the lung. It requires minimal patient cooperation and can be done easily in subjects who are unable to perform spirometry. Importantly, IOS can differentiate small airway obstruction from large airway obstruction and is more sensitive than spirometry for peripheral airway disease. It has been used to study various respiratory disorders, especially asthma and is suitable for measuring bronchodilatory response as well as bronchoprovocation testing. IOS parameters seem to be able to pick up early changes in lung functon such that they are superior to spirometry in predicting loss of control in asthmatic patients and possibly in identifying early airway disease in smokers. Such comparisons, especially for chronic obstructive pulmonary disease, are made difficult by widespread use of spirometric parameters as the diagnostic gold standard. Here, we discuss the principles and technique of IOS and review its application in obstructive airway diseases.

Biomass Smoke Exposure Enhances Rhinovirus-Induced Inflammation in Primary Lung Fibroblasts

Biomass smoke is one of the major air pollutants and contributors of household air pollution worldwide. More than 3 billion people use biomass fuels for cooking and heating, while other sources of exposure are from the occurrence of bushfires and occupational conditions. Persistent biomass smoke exposure has been associated with acute lower respiratory infection (ALRI) as a major environmental risk factor. Children under the age of five years are the most susceptible in developing severe ALRI, which accounts for 940,000 deaths globally. Around 90% of cases are attributed to viral infections, such as influenza, adenovirus, and rhinovirus. Although several epidemiological studies have generated substantial evidence of the association of biomass smoke and respiratory infections, the underlying mechanism is still unknown. Using an in vitro model, primary human lung fibroblasts were stimulated with biomass smoke extract (BME), specifically investigating hardwood and softwood types, and human rhinovirus-16 for 24 h. Production of pro-inflammatory mediators, such as IL-6 and IL-8, were measured via ELISA. Firstly, we found that hardwood and softwood smoke extract (1%) up-regulate IL-6 and IL-8 release (p ≤ 0.05). In addition, human rhinovirus-16 further increased biomass smoke-induced IL-8 in fibroblasts, in comparison to the two stimulatory agents alone. We also investigated the effect of biomass smoke on viral susceptibility by measuring viral load, and found no significant changes between BME exposed and non-exposed infected fibroblasts. Activated signaling pathways for IL-6 and IL-8 production by BME stimulation were examined using signaling pathway inhibitors. p38 MAPK inhibitor SB239063 significantly attenuated IL-6 and IL-8 release the most (p ≤ 0.05). This study demonstrated that biomass smoke can modulate rhinovirus-induced inflammation during infection, which can alter the severity of the disease. The mechanism by which biomass smoke exposure increases inflammation in the lungs can be targeted and inhibited via p38 MAP kinase pathway.

Biomass smoke as a risk factor for chronic obstructive pulmonary disease: effects on innate immunity

Chronic obstructive pulmonary disease (COPD), a major cause of mortality and morbidity worldwide, is considered an archetypical disease of innate immunity, where inhaled particles and gases trigger an inflammatory response, favoring tissue proliferation in small airways and tissue destruction in lung parenchyma, in addition to the recruitment of immune cells to these compartments. Although cigarette smoking is still considered the main risk factor for developing COPD, the trend of proposing biomass smoke (BS) exposure as a principal risk factor is gaining importance, as around 3 billion people worldwide are exposed to this pollutant daily. A considerable amount of evidence has shown the potential of BS as an enhancer of lung inflammation. However, an impairment of some innate immune responses after BS exposure has also been described. Regarding the mechanisms by which biomass smoke alters the innate immune responses, three main classes of cell surface receptors-the TLRs, the scavenger receptors and the transient receptor potential channels-have shown the ability to transduce signals initiated after BS exposure. This article is an updated and comprehensive review of the immunomodulatory effects described after the interaction of BS components with these receptors.

What can reunification of East and West Germany tell us about the cause of the allergy epidemic?

The increase of allergies in East Germany--reaching West German prevalence shortly after the reunification--is considered a model for the allergy epidemic in the western world. Whether such a pattern was observed in all comparison studies and for all allergic manifestations is not known because a complete overview is missing. Hints about possible causal factors for the allergy epidemic could be gained by identifying known risk factors, which explain the observed pattern of allergy development in Germany. Again, an overview about these efforts is missing. We identified 14 cross-sectional studies conducted after 1989 and calculated prevalence ratios (West/East) for asthma, hayfever, eczema and allergic sensitization. Additionally, a tabular overview about the explanatory power of risk factors hypothesized in the nineties and covering outdoor exposure, indoor factors, early childhood influences, nutrition as well as awareness is given. At the time of the German reunification, the prevalence ratio West/East was largest for hayfever and sensitization to birch pollen, less pronounced for the other phenotypes and even less than one for atopic eczema. Hayfever and sensitization to birch pollen also showed the steepest increase in East Germany afterwards. Single-room heating with fossil fuels and living as only child in a family were identified as explaining up to 23.5% of the excess trend in East compared to the trend in West. Hayfever as most typical atopic disease showed the difference in allergy pattern between East and West Germany clearest. Risk factors identified for these phenotypes are completely different (single child) or even act in the opposite direction (single-room heating) from classical risk factors for airway diseases. This might be the most important lesson from the West/East German experience. It already stimulated many other studies focussing on protective factors such as microbial stimulation.

Assessment of the biomass related indoor air pollution in Kwale district in Kenya using short term monitoring

BACKGROUND

Indoor air pollution remains an important health problem in some countries. Although research data on this issue is available, routine monitoring in affected areas is limited. The aims of this study were to quantify exposure to biomass-related indoor air pollution; assess the respiratory health of subjects; and explore the feasibility of routine monitoring in Kwale district, Kenya.

METHODS

We sampled 125 rural houses using short-term monitoring for levels of CO, CO2 and TSP. Additional exposure information was obtained using a checklist. Respiratory health was also assessed using a questionnaire, and electronic spirometer in 172 inhabitants.

RESULTS

The overall median levels of CO in the sampled houses on all study sites ranged from 5.9 (IQR 3-14.5) to 10 (5.5-21.2) mg/m3, levels of CO2 ranged from 774 (IQR 724-846) to 839 (IQR 749-961) mg/m3) and the levels of TSP ranged from 295 (IQR 79-853 to 1384 (IQR 557-3110) µg/m(3) which indicates that safe levels recommended by WHO and USEPA could be exceeded. Relatively high incidences of respiratory illness or symptoms were reported and the spirometry readings suggested impaired lung function in over 80% of respondents.

CONCLUSION

Our results quantify that the use of biomass fuel can give rise to high levels of indoor air pollution. Given that poor lung function contributes to public health problems in rural regions of East Africa, such as Kwale in Kenya, our findings create grounds for more detailed investigations of the problem and may provide motivation for community based interventions.

Wood smoke exposure induces a decrease in respiration parameters and in the activity of respiratory complexes I and IV in lung mitochondria from guinea pigs

Domestic exposure to biomass smoke represents the second cause of chronic obstructive lung disease. Previous studies have shown that exposure of guinea pigs to wood smoke is capable of generating oxidative stress in lung tissue, and this may involve a failure at a mitochondrial level, given its close relation with the production of reactive oxygen species (ROS). The purpose of this study was to evaluate, in guinea pigs exposed to wood smoke, the lung mitochondrial functionality through O2 consumption measurement and the determination of the mitochondrial complexes enzymatic activity. We found that normal and maximum respiration decreased at 15 and 30 min of wood smoke exposure, recovering its normal values at 180 min. The same behavior was observed for the respiratory control rate (RCR) and the ADP/O value. Complex I activity decreased significantly after 30 min of exposure and it returned to baseline after 180 min. The greatest alteration was observed by the decrease of 85% on complex IV activity at 30 min of exposure, which returned to control values after 180 min of exposure. It is concluded that even when wood smoke exposure induces severe mitochondrial respiration alterations at the first 30 min, it seems that there is one or many ways by which mitochondria can reinstate its normal function after 180 min of exposure.

Ethical Issues in Tuberculosis Control

Tuberculosis (TB) remains a major global public health problem as also defined by the World Health Organization (WHO). On the other hand, the incidence of TB worldwide decreases at a lower rate than the intended targets, and it is seen that the targets set for 2015 will not be achieved at the global level. According to the WHO, failure to achieve the targets in TB control results from "resource constraints", "conflict and instability" and "generalized human immunodeficiency virus epidemics". This article is aimed to maintain an ethical debate in TB control and to investigate the WHO's TB control policy and question the reasons for failure of this policy. Within the scope of this article; the TB of TB control was problematized at macro political level within the context of philosophy, while the approach of health care staff to TB patients was analysed at micro level within the context of professional ethics.

Pathogenic mechanisms in chronic obstructive pulmonary disease due to biomass smoke exposure

Chronic obstructive pulmonary disease (COPD) mortality and morbidity have increased significantly worldwide in recent decades. Although cigarette smoke is still considered the main risk factor for the development of the disease, estimates suggest that between 25% and 33% of COPD patients are non-smokers. Among the factors that may increase the risk of developing COPD, biomass smoke has been proposed as one of the most important, affecting especially women and children in developing countries. Despite the epidemiological evidence linking exposure to biomass smoke with adverse health effects, the specific cellular and molecular mechanisms by which this pollutant can be harmful for the respiratory and cardiovascular systems remain unclear. In this article we review the main pathogenic mechanisms proposed to date that make biomass smoke one of the major risk factors for COPD.