Cluster pattern analysis of environmental stressors and quantifying their impact on all-cause mortality in Belgium.

Environmental stress represents an important burden on health and leads to a considerable number of diseases, hospitalisations, and excess mortality. Our study encompasses a representative sample size drawn from the Belgian population in 2016 (n = 11.26 million, with a focus on n = 11.15 million individuals). The analysis is conducted at the geographical level of statistical sectors, comprising a total of n = 19,794 sectors, with a subset of n = 18,681 sectors considered in the investigation. We integrated multiple parameters at the finest spatial level and constructed three categories of environmental stress through clustering: air pollution, noise stress and stress related to specific land-use types. We observed identifiable patterns in the spatial distribution of stressors within each cluster category. We assessed the relationship between age-standardized all-cause mortality rates (ASMR) and environmental stressors. Our research found that especially very high air pollution values in areas where traffic is the dominant local component of air pollution (ASMR + 14,8%, 95% CI: 10,4 - 19,4%) and presence of industrial land (ASMR + 14,7%, 95% CI: 9,4 - 20,2%) in the neighbourhood are associated with an increased ASMR. Cumulative exposure to multiple sources of unfavourable environmental stress (simultaneously high air pollution, high noise, presence of industrial land or proximity of primary/secondary roads and lack of green space) is associated with an increase in ASMR (ASMR + 26,9%, 95% CI: 17,1 - 36,5%).

Évaluation du risque par les professionnels de la santé et les équipes de secours lors d'incidents chimiques.

CONTEXT: The literature review highlights that joint preparation and training of first aid responders is necessary to deal with a major chemical incident. Improved knowledge of exposure assessments makes it possible to estimate the risk and adjust immediate measures. The aim of this paper is to summarize recommendations for assessing exposure during chemical incidents that require emergency responses. Actions allowing the chemical contamination to be better anticipated and health protection to be optimized were analyzed. METHODOLOGY: A review of the literature was conducted, and research questions were formulated using the PECO method. The PRISMA method was used to select the literature. RESULTS AND DISCUSSION: The selected papers (n=16) show that preparation for chemical incidents in terms of individual and collective protective equipment, and knowledge of the risk assessment process remain lacking. We propose training to master the steps of risk assessment. Our analysis also points out the importance of monitoring the state of the environment after a chemical incident, allowing adjusted measures to protect the health of the exposed population and vulnerable groups in particular. This monitoring must be accurate and dynamic to provide realistic recommendations during the intervention phase. CONCLUSIONS: All first-aid responders and health workers knowing the risk assessment process should result in improvements: in the use of protective measures in time and space, the delimitation of exposure to contamination, and the characterization of the risk.

Inequalities in mortality associated with housing conditions in Belgium between 1991 and 2020.

BACKGROUND: Poor housing conditions have been associated with increased mortality. Our objective is to investigate the association between housing inequality and increased mortality in Belgium and to estimate the number of deaths that could be prevented if the population of the whole country faced the mortality rates experienced in areas that are least deprived in terms of housing. METHODS: We used individual-level mortality data extracted from the National Register in Belgium and relative to deaths that occurred between Jan. 1, 1991, and Dec. 31, 2020. Spatial and time-specific housing deprivation indices (1991, 2001, and 2011) were created at the level of the smallest geographical unit in Belgium, with these units assigned into deciles from the most to the least deprived. We calculated mortality associated with housing inequality as the difference between observed and expected deaths by applying mortality rates of the least deprived decile to other deciles. We also used standard life table calculations to estimate the potential years of life lost due housing inequality. RESULTS: Up to 18.5% (95% CI 17.7-19.3) of all deaths between 1991 and 2020 may be associated with housing inequality, corresponding to 584,875 deaths. Over time, life expectancy at birth increased for the most and least deprived deciles by about 3.5 years. The gap in life expectancy between the two deciles remained high, on average 4.6 years. Life expectancy in Belgium would increase by approximately 3 years if all deciles had the mortality rates of the least deprived decile. CONCLUSIONS: Thousands of deaths in Belgium could be avoided if all Belgian neighborhoods had the mortality rates of the least deprived areas in terms of housing. Hotspots of housing inequalities need to be located and targeted with tailored public actions.

An unequal endotoxin distribution in typical house types of Ho Chi Minh city.

BACKGROUND: Endotoxin exposure may cause asthma exacerbations and contribute to non-atopic respiratory diseases. Viet Nam, a country with multiple house types, is lacking data on indoor contamination by endotoxin in regard with house types. OBJECTIVE: The comparison of measured settled dust endotoxin levels among house types in Ho Chi Minh city will allow to classify the house types regarding health risks. METHODS: This study is a cross-sectional study. Five identified house types were selected: apartment (APA), rental (REN), rural (RUR), slum (SLU) and tube house (TUB). One hundred house's endotoxin contamination was evaluated by questionnaire and dust sampling. Endotoxin concentration was measured by kinetic chromogenic Limulus assay. RESULTS: dotoxin concentration (geometric mean 126.0 EU/mg, 95%CI 118.3-133.7) is particularly high in settled house dust compared to western countries and is significantly associated with the house type. The highest level was found in RUR in each room (p = 0.002 for living room; p < 0.0001 for bedrooms and for kitchens). Concerning levels in the different rooms, APA and TUB form a low group while REN and SLU (p < 0.001) form a median group and RUR the highest (p < 0.001). Differences in endotoxin levels were associated to the presence of dog, chicken and farm animals, wood cooking, air-conditioning usage. CONCLUSIONS: Further understanding of the relevant factors to endotoxin levels would contribute to prevent asthma exacerbations and chronic respiratory diseases. Public health interventions to reduce exposure to endotoxin include improving housing conditions, eliminating risk factors and a priority to high-risk house types.

Environment-lockdown, air pollution and related diseases: could we learn something and make it last?

Although the pandemic has caused substantial losses in economic prosperity and human lives, it has also some positive impacts on the environment. Restricted mobility, complete closure, less traffic and industry have led to improved air quality especially in urban settings. Not only is air pollution an important determinant of chronic diseases, such as heart and lung disorders, but it has also been shown that poor air quality increases the risk of COVID-19. In this article, we review some of the findings on changes in air quality during the pandemic, and its potential effects on health. We need to continue to monitor the effects of change in air quality, due to COVID-19 lockdown or other factors, but also keep all our efforts to improve air quality even faster and more persistent, bringing the pollution levels below what WHO recommends are safe to live with.

Leviers et freins à la participation à une étude d'exposition dans l'électrohypersensibilité.

INTRODUCTION: People reporting electromagnetic hypersensitivity (EHS) attribute various functional disorders to their exposure to electromagnetic fields (EMF). To date, the results of provocation studies do not support the existence of a causal relationship between EMF and the reported symptoms. However, these studies suffer from various methodological limitations, including low statistical power due to an insufficient number of volunteers. PURPOSE OF RESEARCH: The objective of this paper is to present the motivations of EHS people who participated in co-creation workshops towards the development of a provocation protocol that would overcome the limitations of existing studies and improve EHS knowledge. RESULTS: In a first phase, participants were invited to discuss the reasons for (not) participating in such a provocation study in order to understand barriers and challenges. Among the drivers, the improvement of the knowledge and the sensitization of the medical profession, as well as the official recognition of EHS and its implications are of great importance. The participants also stress the interest of getting to know themselves better and see the study as a step in the development of therapeutic tools. Among the barriers, people emphasize fears about the project independence and results neutrality, as well as methodological choices. Some also highlight the consequences of the test on their health (suffering) and social aspects. CONCLUSIONS: We identify precautions and recommendations for the implementation of a collaborative work with EHS people and in their perennial inclusion in an exposure study.

Co-Designed Exposure Protocol in the Study of Idiopathic Environmental Intolerance Attributed to Electromagnetic Fields.

The hypothesis of an electromagnetic origin of idiopathic environmental intolerance (IEI) attributed to electromagnetic fields (EMF) has been widely investigated by provocation studies, which consist of deliberately exposing people with IEI-EMF in laboratory settings to particular EMF to observe volunteers' reactions. In the majority of these studies, reactions have been found to be independent of exposure. However, most of these studies suffer from design and methodological limitations that might bias their findings or reduce their precision. As provocation studies are best suited for isolating the effects of EMF, innovative protocols should be applied. In the ExpoComm project (PNREST Anses, EST/2017/2 RF/19), several innovations have been introduced: the involvement of people with IEI-EMF in the development of the protocol, the attenuation of the anxiogenic nature of the tests, the individualization of the protocol, the validation of the neutral or normal reactivity state before the test, and the use of a cocktail of real, rather than artificially generated, sources. The objective of involving people with IEI-EMF was to increase the relevance and acceptability of the protocol, while respecting technical constraints and scientific quality requirements. This paper describes the protocol resulting from the collaborative process. Bioelectromagnetics. 2020;41:425-437. © 2020 Bioelectromagnetics Society.

[Promoting the sustainable management of hospital waste in Kinshasa]. / Réflexion en faveur d'une gestion durable des déchets hospitaliers à Kinshasa.

The management of hospital waste is a high-risk practice in the hospitals of Kinshasa, the largest city of the Democratic Republic of the Congo, from the point of view of public health and the environment. A multi-criteria study carried out in 4 hospitals assessed the situation and put forward solutions.

BTEX air concentrations and self-reported common health problems in gasoline sellers from Cotonou, Benin.

To examine the relation between BTEX exposure levels and common self-reported health problems in 140 gasoline sellers in Cotonou, Benin, a questionnaire documenting their socioeconomic status and their health problems was used, whereas 18 of them went through semi-directed qualitative individual interviews and 17 had air samples taken on their workplace for BTEX analysis. Median concentrations for BTEX were significantly lower on official (range of medians: 54-207 µg/m³, n = 9) vs unofficial (148-1449 µg/m³, n = 8) gasoline-selling sites (p < 0.05). Self-reported health problems were less frequently reported in sellers from unofficial vs official selling sites (p < 0.05), because, as suggested by the semi-directed interviews, of their fear of losing their important, but illegal, source of income. Concluding, this study has combined quantitative and qualitative methodological approaches to account for the complex socioeconomic and environmental conditions of the investigated sellers, leading to their, in some cases, preoccupying BTEX exposure.

Chronic burden of near-roadway traffic pollution in 10 European cities (APHEKOM network).

Recent epidemiological research suggests that near road traffic-related pollution may cause chronic disease, as well as exacerbation of related pathologies, implying that the entire "chronic disease progression" should be attributed to air pollution, no matter what the proximate cause was. We estimated the burden of childhood asthma attributable to air pollution in 10 European cities by calculating the number of cases of 1) asthma caused by near road traffic-related pollution, and 2) acute asthma events related to urban air pollution levels. We then expanded our approach to include coronary heart diseases in adults. Derivation of attributable cases required combining concentration-response function between exposures and the respective health outcome of interest (obtained from published literature), an estimate of the distribution of selected exposures in the target population, and information about the frequency of the assessed morbidities. Exposure to roads with high vehicle traffic, a proxy for near road traffic-related pollution, accounted for 14% of all asthma cases. When a causal relationship between near road traffic-related pollution and asthma is assumed, 15% of all episodes of asthma symptoms were attributable to air pollution. Without this assumption, only 2% of asthma symptoms were attributable to air pollution. Similar patterns were found for coronary heart diseases in older adults. Pollutants along busy roads are responsible for a large and preventable share of chronic disease and related acute exacerbations in European urban areas.

Impact of filtering face pieces (FFP3) respiratory protective mask usage on the respiratory functions of informal sector carpenters in Douala: a five-month before-after study.

Introduction: informal sector carpenters in Douala, Cameroon, face potential risks to their respiratory health due to daily exposure to fine particles and wood dust. The study aims to demonstrate the importance of preventing respiratory problems in this population through regular use of filtering face pieces (FFP3) respiratory masks. Methods: the before-after study involved 37 carpenters who wore FFP3 masks during their professional activities for five months. Spirometry measurements were taken before and after the intervention to assess changes in respiratory function. Results: significant improvements were observed in forced vital capacity (FVC) 89.6 % to 95.0 % (p<0.000), forced expiratory volume in one second (FEV1) 88.1 % to 95.0 % (p<0.000), Tiffeneau index 82.4 to 84.9 (p<0.000), and peak expiratory flow (PEF) 6.7 l/s to 7.9 l/s (p<0.000) after mask usage, indicating enhanced lung function. Conclusion: the regular use of FFP3 masks had a positive impact on the respiratory health of informal sector carpenters in Douala, enhancing lung function and reducing airway obstruction. The study highlights the importance of preventive measures to safeguard the respiratory well-being of workers exposed to occupational hazards. Spell out Greek characters (i.e: alpha, beta).

Measuring small-area level deprivation in Belgium: The Belgian Index of Multiple Deprivation.

BACKGROUND: In the past, deprivation has been mostly captured through simple and univariate measures such as low income or poor educational attainment in research on health and social inequalities in Belgium. This paper presents a shift towards a more complex, multidimensional measure of deprivation at the aggregate level and describes the development of the first Belgian Indices of Multiple Deprivation (BIMDs) for the years 2001 and 2011. METHODS: The BIMDs are constructed at the level of the smallest administrative unit in Belgium, the statistical sector. They are a combination of six domains of deprivation: income, employment, education, housing, crime and health. Each domain is built on a suite of relevant indicators representing individuals that suffer from a certain deprivation in an area. The indicators are combined to create the domain deprivation scores, and these scores are then weighted to create the overall BIMDs scores. The domain and BIMDs scores can be ranked and assigned to deciles from 1 (the most deprived) to 10 (the least deprived). RESULTS: We show geographical variations in the distribution of the most and least deprived statistical sectors in terms of individual domains and overall BIMDs, and we identify hotspots of deprivation. The majority of the most deprived statistical sectors are located in Wallonia, whereas most of the least deprived statistical sectors are in Flanders. CONCLUSION: The BIMDs offer a new tool for researches and policy makers for analyzing patterns of deprivation and identifying areas that would benefit from special initiatives and programs.

Health effects of extremely low-frequency magnetic fields: reconsidering the melatonin hypothesis in the light of current data on magnetoreception.

The so-called 'Melatonin Hypothesis' proposed that decreased nocturnal production of melatonin (MLT) might explain the increased risk of breast cancer that has been formerly attributed to extremely low-frequency (ELF) magnetic fields (MF) of weak intensity. Although the risk of ELF MF upon breast cancer was later dismissed, repeated reports were published of partial inhibition of MLT secretion in rats under long-term (≥ 4 weeks) exposure to weak ELF MF. Since 2004, however, this topic has not been experimentally studied any more. In the present study, we propose to go back to the MLT hypothesis and apply it to childhood leukemia, for which an increased risk has been robustly associated with residential exposure to ELF MF. Contrary to the original hypothesis, however, we do not consider decreased MLT levels, but disruption of circadian rhythmicity per se as the effector mechanism. Indeed, the role of the circadian timing system in the development of childhood leukemia has been well established. Motivation for going back to the MLT hypothesis comes from recent data that suggest magnetosensory disruption by ELF MF in mammals, and magnetosensitivity in humans, together with current evidence for an influence on circadian rhythmicity from disruption of non-photic sensory stimuli of various natures. We thus suggest further study on circadian rhythmicity in humans (children if possible) under long-term exposure to weak ELF MF.

Environmental Heavy Metal Contamination from Electronic Waste (E-Waste) Recycling Activities Worldwide: A Systematic Review from 2005 to 2017.

The recycling of electronic waste (e-waste) contaminates ecosystems with metals, though a compilation of data from across sites worldwide is lacking, without which evidence-based comparisons and conclusions cannot be realized. As such, here, a systematic review of the literature was conducted to identify peer-reviewed studies concerning e-waste sites (published between 2005 and 2017) that reported on the concentration of heavy metals (Cd, Hg, As, Pb and Cr) in soil, water and sediment. From 3063 papers identified, 59 studies from 11 countries meeting predefined criteria were included. Reported metal concentrations were summarized, and a narrative synthesis was performed. This review summarized 8286 measurements of the aforementioned metals in soils (5836), water (1347) and sediment (1103). More than 70% of the studies were conducted in Asia. In nearly all cases, the average metal concentrations in a particular medium from a given site were above guideline values; suggesting soils, water and sediment at, or near, e-waste recycling sites are contaminated. Across all media, concentrations of Pb were generally highest, followed by Cr, As, Cd and Hg. The synthesized information demonstrates that e-waste sites worldwide are contaminated with metals, that geographic data gaps exist, that the quality of most studies can be improved and that action is needed to help reduce such levels to protect human health and the environment.

On the importance of primary and community healthcare in relation to global health and environmental threats: lessons from the COVID-19 crisis.

In the course of the COVID-19 pandemic, it has become clear that primary healthcare systems play a critical role in clinical care, such as patient screening, triage, physical and psychological support and also in promoting good community advice and awareness in coordination with secondary healthcare and preventive care. Because of the role of social and environmental factors in COVID-19 transmission and burden of disease, it is essential to ensure that there is adequate coordination of population-based health services and public health interventions. The COVID-19 pandemic has shown the primary and community healthcare (P&CHC) system's weaknesses worldwide. In many instances, P&CHC played only a minor role, the emphasis being on hospital and intensive care beds. This was compounded by political failures, in supporting local community resilience. Placing community building, social cohesion and resilience at the forefront of dealing with the COVID-19 crisis can help align solutions that provide a vision of 'planetary health'. This can be achieved by involving local well-being and participation in the face of any pervasive health and environmental crisis, including other epidemics and large-scale ecological crises. This paper proposes that P&CHC should take on two critical roles: first, to support local problem-solving efforts and to serve as a partner in innovative approaches to safeguarding community well-being; and second, to understand the local environment and health risks in the context of the global health perspective. We see this as an opportunity of immediate value and broad consequence beyond the control of the COVID-19 pandemic.

Household energy choice for domestic cooking: distribution and factors influencing cooking fuel preference in Ouagadougou.

Many studies have highlighted the link between indoor air pollution from the burning of solid fuels for cooking and heating and the occurrence of various health problems particularly in women and children under 5 years. In developing countries, solid fuels remain the main sources of energy. The purpose of this study aims to describe the distribution of household cooking fuel types and to analyze the factors influencing household cooking energy choice in Ouagadougou. A cross-sectional survey was conducted in 2017 in 3 neighborhoods of Ouagadougou. A total of 1734 household were randomly selected. We performed a multivariable logistic regression and a multinomial logistic regression to measure the relationship between selected determinants and households' primary cooking fuel. 59.53% of the households of Ouagadougou reported using solid fuels as the main cooking fuel. Wood is the most common primary cooking fuel used (43.93%), followed by LPG (40.41%) and then charcoal (15.60%). About 84% combine at least 2 types of energy for cooking. Cooking fuel choice is strongly influenced by the socioeconomic status, the family size, and also by the woman's educational attainment, her age and the main cooking fuel used in her parents' house. Actions aimed at reducing the impact of solid fuel use in the environment or health must consider these factors.

Primary Cooking Fuel Choice and Respiratory Health Outcomes among Women in Charge of Household Cooking in Ouagadougou, Burkina Faso: Cross-Sectional Study.

Background: Approximately 3 billion people, worldwide, rely primarily on biomass for cooking. This study aimed to investigate the association between respiratory symptoms among women in charge of household cooking and the type of fuel used for cooking. Methods: A community-based cross-sectional survey was conducted. A total of 1705 women that were randomly selected, completed the survey. We also performed a bivariate and a multivariate analysis to verify the possible associations between respiratory symptoms in women in charge of household cooking and the type of cooking fuel used. Results: Dry cough, breathing difficulties, and throat irritation frequencies were statistically high in biomass fuel users when compared to liquefied petroleum gas (LPG) users. It was also the case for some chronic respiratory symptoms, such as sputum production, shortness of breath, wheezing, wheezing with dyspnea, wheezing without a cold, waking up with shortness of breath, waking up with coughing attacks, and waking up with breathing difficulty. After adjustment for the respondents' and households' characteristics; dry cough, breathing difficulties, sneezing, nose tingling, throat irritation, chronic sputum production, wheezing, wheezing with dyspnea, wheezing without a cold, waking up with shortness of breath, waking up with coughing attacks, and waking up with breathing difficulty were symptoms that remained associated to biomass fuel compared to LPG. Women who used charcoal reported the highest proportion of all the chronic respiratory symptoms compared to the firewood users. However, this difference was not statistically significant except for the wheezing, waking up with coughing attacks, and waking up with breath difficulty, after adjustment. Conclusion: Exposure to biomass smoke is responsible for respiratory health problems in women. Charcoal, which is often considered as a clean fuel compared to other biomass fuels and often recommended as an alternative to firewood, also presents health risks, including increased respiratory morbidity in women. Effective and efficient energy policies are needed to accelerate the transition to clean and sustainable energies.

The EMPCAN study: protocol of a population-based cohort study on the evolution of the socio-economic position of workers with cancer.

BACKGROUND: The improvements in cancer control led to an increase in the number of cancer survivors, notably, in the working age population (16-64 years). There is a strong need to assess and understand their reintegration on the labour market, which underlines and ensures their social integration and quality of life. The objectives of the EMPCAN study is therefore to measure the scale of return-to-work after cancer and to identify the determining factors, allowing for the implementation of an adequate socio-professional support. METHODS: We requested data from the Belgian Cancer Registry and the Crossroad Bank for Social Security. We included all socially insured Belgian workers diagnosed between 2004 and 2011 with colorectal, breast, head & neck, prostate, testis, lung and corpus uteri cancer. The end of (administrative) follow-up was 31st December 2012. We include demographic, health-related and work-related factors in the analysis and observed how these factors interplay to determine the working status. After having solved legal, ethical and technical issues for the coupling, we will perform survival analysis with competing risks using the Fine and Gray model; we will also perform a multistate model using transitions probabilities; and finally, a group-based modeling for longitudinal data using the 'proc traj' package in SAS. DISCUSSION: The results of the EMPCAN study will allow the provision of an evidence-based support to professional reintegration policies. It will also bring some key features for the prediction of the cancer-related social security needs. Besides the raise of awareness among health professionals and policy makers, this study could lead to a better planning and organization of vocational rehabilitation programs.

The protective effect of rural life on mite sensitization disappears among urban migrants in the South of Vietnam.

BACKGROUND: Rapid urbanization combined with rural migration to urban areas in southern Vietnam could be risk factors for allergen sensitization, contributing to chronic respiratory diseases (CRD). We aimed to evaluate the prevalence of mite sensitization and its relation to house dust characteristics among rural and urban native and migrating populations with CRD. METHODS: Rural (n = 19) and urban (n = 46) dwellings were defined on the basis of a home typology. Controls were western Belgian houses (n = 14). Besides the house characteristics, both endotoxin and mite allergens were measured in the settled dusts. The sensitization to mite allergens was defined by positive skin prick test (SPT) and concentration of specific IgE (sIgE)≥ 0.7 U/mL. The prevalence of mite sensitization was evaluated among 610 patients with CRD and compared according to both their home types and places of birth and residences. RESULTS: The concentration of endotoxin (but not mite allergen) was higher in rural compared to urban dusts (440 (95%CI: 314-566) versus 170 (95%CI: 115-226) EU/mg; p < 0.0001). The prevalence of positive sIgE to Der p1 and Der p2 was significantly lower in rural (9% and 5%) compared to urban (15% and 9%) population, consistent with the positive SPT to mite (14% and 21%, respectively). Among the urban migrants, the risk of mite sensitization (SPT) was higher compared to the rural natives (OR: 1.79 (1.02-3.15), p < 0.05) and not different to the urban ones (OR: 1.35 (0.82-2.23) p NS). CONCLUSION: In Vietnam, associated with higher endotoxin (but not allergen) dust concentrations, the risk of mite sensitization was lower in rural compared to the native urban population, but this protective effect could disappear among rural to urban migrants.

Chronic obstructive pulmonary disease associated with biomass fuel use in women: a systematic review and meta-analysis.

INTRODUCTION: Chronic obstructive pulmonary disease (COPD) is a major and growing cause of morbidity and mortality worldwide. The global prevalence of COPD is growing faster in women than in men. Women are often exposed to indoor pollutants produced by biomass fuels burning during household activities. METHODS: We conducted a meta-analysis to establish the association between COPD and exposure to biomass smoke in women.Following Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines, we searched MEDLINE and Scopus databases in 31December 2016, with the terms: "wood", "charcoal", "biomass", "solid fuels", "organic fuel", "biofuel", "female", "women", "COPD", "chronic bronchitis", "emphysema", "chronic obstructive pulmonary disease". Studies were eligible if they were case-control or cross-sectional studies involving exposure to indoor biomass smoke, conducted at any time and in any geographic location. Fixed-effects or random-effects meta-analysis was used to generate pooled OR. RESULTS: 24 studies were included: 5 case-control studies and 19 cross-sectional studies. Biomass-exposed individuals were 1.38 times more likely to be diagnosed with COPD than non-exposed (OR 1.38, 95% CI 1.28 to 1.57).Spirometry-diagnosed COPD studies failed to show a significant association (OR 1.20, 95% CI 0.99 to 1.40). Nevertheless, the summary estimate of OR for chronic bronchitis (CB) was significant (OR 2.11, 95% CI 1.70 to 2.52). The pooled OR for cross-sectional studies and case-control studies were respectively 1.82 (95% CI 1.54 to 2.10) and 1.05 (95% CI 0.81 to 1.30). Significant association was found between COPD and biomass smoke exposure for women living as well in rural as in urban areas. CONCLUSIONS: This study showed that biomass smoke exposure is associated with COPD in rural and urban women.In many developing countries, modern fuels are more and more used alongside traditional ones, mainly in urban area. Data are needed to further explore the benefit of the use of mixed fuels for cooking on respiratory health, particularly on COPD reduction.