National burden of disease in India from indoor air pollution

Assessing personal PM2.5 exposure using a novel neck-mounted monitoring device in rural Rwanda

There is growing global concern regarding the detrimental health impacts of PM2.5 emissions from traditional stoves that utilize polluting fuels. Conventional methods for estimating daily personal PM2.5 exposure involve personal air samplers and measuring devices placed in a waist pouch, but these instruments are cumbersome and inconvenient. To address this issue, we developed a novel neck-mounted PM2.5 monitoring device (Pocket PM2.5 Logger) that is compact, lightweight, and can operate continuously for 1 week without recharging. Twelve participants who utilized charcoal, firewood, or propane gas for cooking in rural regions of Rwanda wore the Pocket PM2.5 Logger continuously for 1 week, and time-series variations in personal PM2.5 exposure were recorded at 5-min intervals. Individual daily exposure concentrations during cooking differed significantly among users of the different fuel types, and PM2.5 exposure was at least 2.6 and 3.4 times higher for charcoal and firewood users, respectively, than for propane gas users. Therefore, switching from biomass fuels to propane gas would reduce daily individual exposure by at least one-third. An analysis of cooking times showed that the median cooking time per meal was 30 min; however, half the participants cooked for 1.5 h per meal, and one-third cooked for over 4.5 h per meal. Reducing these extremely long cooking times would reduce exposure with all fuel types. The Pocket PM2.5 Logger facilitates the comprehensive assessment of personal PM2.5 exposure dynamics and is beneficial for the development of intervention strategies targeting household air pollution.

The Comet Assay as a Tool in Human Biomonitoring Studies of Environmental and Occupational Exposure to Chemicals-A Systematic Scoping Review

Biomonitoring of human populations exposed to chemical substances that can act as potential mutagens or carcinogens, may enable the detection of damage and early disease prevention. In recent years, the comet assay has become an important tool for assessing DNA damage, both in environmental and occupational exposure contexts. To evidence the role of the comet assay in human biomonitoring, we have analysed original research studies of environmental or occupational exposure that used the comet assay in their assessments, following the PRISMA-ScR method (preferred reporting items for systematic reviews and meta-analyses extension for scoping reviews). Groups of chemicals were designated according to a broad classification, and the results obtained from over 300 original studies (n = 123 on air pollutants, n = 14 on anaesthetics, n = 18 on antineoplastic drugs, n = 57 on heavy metals, n = 59 on pesticides, and n = 49 on solvents) showed overall higher values of DNA strand breaks in the exposed subjects in comparison with the unexposed. In summary, our systematic scoping review strengthens the relevance of the use of the comet assay in assessing DNA damage in human biomonitoring studies.

A comprehensive review of microbial contamination in the indoor environment: sources, sampling, health risks, and mitigation strategies

The quality of the indoor environment significantly impacts human health and productivity, especially given the amount of time individuals spend indoors globally. While chemical pollutants have been a focus of indoor air quality research, microbial contaminants also have a significant bearing on indoor air quality. This review provides a comprehensive overview of microbial contamination in built environments, covering sources, sampling strategies, and analysis methods. Microbial contamination has various origins, including human occupants, pets, and the outdoor environment. Sampling strategies for indoor microbial contamination include air, surface, and dust sampling, and various analysis methods are used to assess microbial diversity and complexity in indoor environments. The review also discusses the health risks associated with microbial contaminants, including bacteria, fungi, and viruses, and their products in indoor air, highlighting the need for evidence-based studies that can relate to specific health conditions. The importance of indoor air quality is emphasized from the perspective of the COVID-19 pandemic. A section of the review highlights the knowledge gap related to microbiological burden in indoor environments in developing countries, using India as a representative example. Finally, potential mitigation strategies to improve microbiological indoor air quality are briefly reviewed.

Urban-rural disparity in global estimation of PM2·5 household air pollution and its attributable health burden

BACKGROUND

Polluting fuels and inefficient stove technologies are still a leading cause of premature deaths worldwide, particularly in low-income and middle-income countries. Previous studies of global household air pollution (HAP) have neither considered the estimation of PM2·5 at national level nor the corresponding attributable mortality burden. Additionally, the effects of climate and ambient air pollution on the global estimation of HAP-PM2·5 exposure for different urban and rural settings remain largely unknown. In this study, we include climatic effects to estimate the HAP-PM2·5 exposure from different fuel types and stove technologies in rural and urban settings separately and the related attributable global mortality burden.

METHODS

Bayesian hierarchical models were developed to estimate an annual average HAP-PM2·5 personal exposure and HAP-PM2·5 indoor concentration (including both outdoor and indoor sources). Model variables were selected from sample data in 282 peer-reviewed studies drawn and updated from the WHO Global HAP dataset. The PM2·5 exposure coefficients from the developed model were applied to the external datasets to predict the HAP-PM2·5 exposure globally (personal exposure in 62 countries and indoor concentration in 69 countries). Attributable mortality rate was estimated using a comparative risk assessment approach. Using weighted averages, the national level 24 h average HAP-PM2·5 exposure due to polluting and clean fuels and related death rate per 100 000 population were estimated.

FINDINGS

In 2020, household use of polluting solid fuels for cooking and heating led to a national-level average personal exposure of 151 μg/m3 (95% CI 133-169), with rural households having an average of 171 μg/m3 (153-189) and urban households an average of 92 μg/m3 (77-106). Use of clean fuels gave rise to a national-level average personal exposure of 69 μg/m3 (62-76), with a rural average of 76 μg/m3 (69-83) and an urban average of 49 μg/m3 (46-53). Personal exposure-attributable premature mortality (per 100 000 population) from the use of polluting solid fuels at national level was on average 78 (95% CI 69-87), with a rural average of 82 (73-90) and an urban average of 66 (57-75). The average attributable premature mortality (per 100 000 population) from the use of clean fuels at the national level is 62 (54-70), with a rural average of 66 (58-74) and an urban average of 52 (47-57). The estimated HAP-PM2·5 indoor concentration shows that the use of polluting solid fuels resulted in a national-level average of 412 μg/m3 (95% CI 353-471), with a rural average of 514 μg/m3 (446-582) and an urban average of 149 μg/m3 (126-173). The use of clean fuels (gas and electricity) led to an average PM2·5 indoor concentration of 135 μg/m3 (117-153), with a rural average of 174 μg/m3 (154-195) and an urban average of 71 μg/m3 (63-80). Using time-weighted HAP-PM2·5 indoor concentrations, the attributable premature death rate (per 100 000 population) from the use of polluting solid fuels at the national level is on average 78 (95% CI 72-84), the rural average being 84 (78-91) and the urban average 60 (54-66). From the use of clean fuels, the average attributable premature death rate (per 100 000 population) at the national level is 59 (53-64), the rural average being 68 (62-74) and the urban average 45 (41-50).

INTERPRETATION

A shift from polluting to clean fuels can reduce the average PM2·5 personal exposure by 53% and thereby lower the death rate. For all fuel types, the estimated average HAP-PM2·5 personal exposure and indoor concentrations exceed the WHO's Interim Target-1 average annual threshold. Policy interventions are urgently needed to greatly increase the use of clean fuels and stove technologies by 2030 to achieve the goal of affordable clean energy access, as set by the UN in 2015, and address health inequities in urban-rural settings.

FUNDING

Wellcome Trust, The Lancet Countdown, the Engineering and Physical Sciences Research Council, and the Natural Environment Research Council.

Exposure to indoor air pollution and the cognitive functioning of elderly rural women: a cross-sectional study using LASI data, India

BACKGROUND

The majority of people in rural developing counties still rely on unclean and solid fuels for cooking, putting their health at risk. Adult and elderly women are most vulnerable due to prolonged exposure in cooking areas, and Indoor Air Pollution (IAP) may negatively impact their health and cognitive function. This study examines the effect of IAP on the cognitive function of middle-aged and elderly rural women in India.

METHODS

The study utilized the data from the Longitudinal Ageing Study in India (LASI 2017-18, Wave-1). Bivariate analysis and multilevel linear regression models were applied to show the association between IAP and the cognitive abilities of rural women and results from regression were presented by beta coefficient (β) with 95% confidence interval (CI). Confounding factors such as age, education, health risk behaviours, marital status, monthly per capita consumption expenditure (MPCE), religion etc. were adjusted in the final model.

RESULTS

The study found that 18.71 percent of the rural women (n = 3,740) lived in Indoor Air Pollution exposed households. IAP was significantly found to be associated with the cognitive functional abilities among the middle and older aged rural women. Middle and older aged rural women exposed to IAP had lower cognitive functional abilities than non-exposed women. Comparing to the non-exposed group, the cognitive score was worse for those exposed to IAP in both the unadjusted (β = -1.96; 95%CI: -2.22 to -1.71) and the adjusted (β = -0.72; 95%CI: -0.92 to -0.51) models. Elderly rural women from lower socioeconomic backgrounds were more likely to have cognitive impairment as a result of IAP.

CONCLUSION

Findings revealed that IAP from solid fuels could significantly affect the cognitive health of elderly rural women in India, indicating the need for immediate intervention efforts to reduce the use of solid fuels, IAP and associated health problems.

A scientometric analysis of indoor air pollution research during 1990-2019

Indoor air pollution (IAP) is one of the leading risk factors for various adverse health outcomes including premature deaths globally. Even though research related to IAP has been carried out, bibliometric studies with particular emphasis on this topic have been lacking. Here, we investigated IAP research from 1990 to 2019 retrieved from the Web of Science database through a comprehensive and systematic scientometric analysis using the CiteSpace 5.7.R2, a powerful tool for visualizing structural, temporal patterns and trends of a scientific field. There was an exponential increase in publications, however, with a stark difference between developed and developing countries. The journals publishing IAP related research had multiple disciplines; 'Indoor Air' journal that focuses solely on IAP issues ranked fifth among top-cited journals. The terms like 'global burden', 'comparative risk assessment,' 'household air pollution (HAP)', 'ventilation', 'respiratory health', 'emission factor', 'impact,' 'energy', 'household', 'India' were the current topical subject where author Kirk R. Smith was identified with a significant contribution. Research related to rural, fossil-fuel toxicity, IAP, and exposure-assessment had the highest citation burst signifying the particular attention of scientific communities to these subjects. Overall, this study examined the evolution of IAP research, identified the gaps and provided future research directions.

Assessing managerial patient safety practices that influence adverse events reporting among nurses in the Savannah Region, Ghana

Introduction

Patient safety is a global concern for both health professionals and the public. Studies show that evaluating patient safety culture can help improve patient safety outcomes. Nursing care strategically places nurses at the centre of patient safety promotion and their proximity to patients makes them the drivers of patient safety. Managerial decisions regarding patient safety impact greatly on patient safety outcomes in the healthcare organization. This study aimed to assess the managerial patient safety practices that influence adverse event reporting in three hospitals in the Savannah Region of Ghana.

Methods

A quantitative cross-sectional design was used to collect data from 210 participants in three hospitals. Data were analysed using descriptive, Pearson's correlation and linear regression.

Results

It was found that patient safety practices with good positive rating scores were management support (56.6%), managers' expectations (62.8%) and feedback about errors (56.2%). Areas with weak patient safety practices were staffing levels (42.4%), open communication (40.2%) and non-punitive response to errors (36.7%). Again, nurses' attitude towards adverse events reporting was generally low (37.3%). Managerial patient safety practices that had significant associations with adverse events reporting were management support ( r = .18, p < .001), open communication ( r = .19, p < .001), non-punitive to errors ( r = .21, p < .001) and feedback about errors ( r = .37, p < .001). Again, the significant predictors of adverse events reporting were feedback about errors ( β  =  .36, p < .001) and non-punitive response to errors ( β  =  .21, p  < .01).

Conclusion

Nurses perceived patient safety culture in their units to be good. Although nurses' attitude towards adverse events reporting was low, the significant predictors of adverse events reporting were feedback about errors and non-punitive response to errors. Therefore, healthcare managers should continually strengthen patient safety to ensure optimal care outcomes.

Implications for nursing practice

Feedback on errors and non-punitive response to errors had a great influence on adverse events reporting, managerial failure to provide feedback and a non-punitive work environment could result in under-reporting of adverse events. This can be a major threat to patient safety; hence clinical practice should be aware of this and put in strategies to appropriately address them.

Photoinduced evolution of optical properties and compositions of methoxyphenols by Fe(III)-carboxylates complexes in atmospheric aqueous phase

The changes in optical properties and chemical compositions of methoxyphenols, which acted as an important aromatic compound from the biomass burning, were investigated in the presence of Fe(III)-carboxylates under aqueous phase conditions. The light was confirmed to be a key factor for stimulating the reaction of methoxyphenols and Fe(III)-carboxylates. The photoinduced evolution of optical properties of methoxyphenols was dependent on various factors, including irradiation intensity, types of carboxylates, dissolved oxygen and pH. The changes in the mass absorption efficiency at 306 nm (MAE₃₀₆) positively relied on irradiation intensity and dissolved oxygen. The acceleration effects of carboxylates on the decreases in MAE₃₀₆ of methoxyphenols followed the order of oxalate > citrate > malonate. The change amplitude of MAE₃₀₆ decreased with an increasing pH (3.5-9), while that of the mass absorption efficiency at 364 nm (MAE₃₆₄) increased with pH ranging from 3.5 to 7. The compositional evolutions of methoxyphenols by the photochemical aging were analyzed with the attenuated total reflection infrared spectroscopy (ATR-IR), confirming the decrease of CO groups and the increase of O-H and C-O groups. The photochemical reaction pathways of methoxyphenols with Fe(III)-carboxylates were proposed according to optical properties and compositions measurements.

Study to evaluate the socio-demographic and environmental factors affecting morbidity and mortality of community acquired pneumonia in children <5years

Aim: To evaluate the socio demographic and environmental factors affecting morbidity and mortality of community acquired pneumonia in children <5years. Materials and methods: The present Observational longitudinal study was carried in the Department of Paediatrics, Dr. D.Y. Patil Medical College, Pune, among 70 children less than 5 years of age admitted in the In-patient department , Neonatal Intensive Care Unit and Paediatric Intensive Care Unit diagnosed as community acquired pneumonia of either sex in the hospital. The study was carried out from may 2019-september 2021. The children who fulfilled the WHO criteria of Community Acquired Pneumonia were in addition to the Chest x-ray and investigations findings suggestive of CAP were enrolled. The details of the patient's personal and demographic profile, clinical presentation, underlying condition, laboratory investigations, therapy and course in the hospital, and the final outcome were all recorded on a pre-designed proforma. Results: Mean age of children presenting with pneumonia (31.92 months) was approximately similar with those presenting with severe pneumonia (30.37 months).

Risk factors for chronic obstructive pulmonary disease in never‐smokers: A systematic review

Introduction

Relatively little is known about the risk factors for chronic obstructive pulmonary disease (COPD) in never‐smokers, and these factors have not yet been fully characterised. This study therefore sought to analyse COPD risk factors in never‐smokers by conducting a systematic review of the literature on the topic.

Materials and methods

We performed a search in PubMed (Medline) and Embase from 2000 onwards, to locate studies on COPD in never‐smokers. For literature search and evidence synthesis purposes, we used the PRISMA guidelines and drew up a specific quality scale to quantify the evidence of each study included.

Results

The bibliographic search retrieved a total of 557 papers, 20 of which fulfilled the designated inclusion criteria (two case–control studies, four cohort studies and 14 cross‐sectional studies). These studies were undertaken in Europe, the United States, Latin America, Asia and Africa. The risk factors for never‐smokers were varied and ranged from exposure to biomass, occupational exposure and passive smoking to having a history of asthma, tuberculosis or respiratory infections during childhood. The effect of residential radon was unclear. The highest risk was obtained for previous respiratory diseases of any type, with a magnitude much higher than that observed for other risk factors.

Conclusions

There are few studies on COPD risk factors in never‐smokers. More purpose‐designed studies in this subpopulation are thus called for, including well‐designed studies to specifically assess if indoor radon has any role on COPD onset.

Particulate matter exposure in biomass-burning homes of different communities of Brahmaputra Valley

Biomass burning for cooking prevalent in the developing countries is an issue which has been a concern for the past several decades for the noxious emissions and subsequent effects on the health of women and children due to the exposure of particulate matter (PM) and other gases. In this study, PM (PM₁, PM_2.5, and PM₁₀) were measured in biomass-burning households for different communities of Brahmaputra Valley region northeast India by a 31-channel aerosol spectrometer. The levels of emission of PM in the case of different community households were found to be significantly different. Also, the emission characteristics of different cooking time of the day were found to be different across communities. The emission levels in the biomass-burning households were compared with emission in household using "clean" LPG fuel, and it was found that the biomass fuels emitted 10-12 times more PM_2.5 and 6-7 times more PM₁₀. The number densities of the emission were found to be more with smaller sizes of particulates which could explain why such biomass-burning emissions can pose with greater health risks. The exposure doses were calculated and were found to be about three times higher in biomass-burning houses than "clean" LPG fuel. It is important to note that the exposure from biomass burning while cooking has a gender perspective. The woman of the house generally takes care of the activities in the kitchen and get exposed to the noxious PM and the gases. Children often accompany their mothers and face the same fate.

Gender and LPG use after government intervention in rural north India

Exposure to air pollution from cooking with solid fuels has important consequences for public health. This paper focuses on rural north India, where despite robust economic growth and government subsidies, the vast majority of households mainly use solid fuels. We draw on new qualitative and quantitative data collected in the context of a policy environment that dramatically expanded ownership of liquid petroleum gas (LPG) to examine why households are slow to adopt clean fuels in rural north India. We find that patriarchal gender norms and attitudes encourage the use of solid fuels in this region. North Indian society confers low status to women, promotes women's seclusion, and constrains women's engagement in economic activities outside of the home. These beliefs encourage women to preserve gas, promote women's work that facilitates the use of solid fuels, and hinder communication between the cook and the decision-maker regarding LPG refills. When rural north Indian households use gas, it is frequently to facilitate the adherence to norms of seclusion that prevent women from leaving the home to collect solid fuels. In addition to expanding access and improving economic conditions, future research and policy interventions should pay careful attention to the gender norms and attitudes that discourage the use of gas. Addressing these beliefs and norms is essential to sustained LPG use and health improvements.

Exposure and perception of PM2.5 pollution on the mental stress of pregnant women

Prenatal exposure to ambient PM_2.5 has been proved to be related to pregnant women's physical health and birth outcomes. However, the damage from air pollution on pregnant women's mental health has not been fully discussed. A case-control study was conducted to evaluate the effects of PM_2.5 exposure and risk perception on the mental stress of pregnant women. A total of 605 pregnant women, including 403 high symptoms of stress cases and 202 matched controls, were recruited from January 2018 to December 2018 in Nanjing, among which 313 high symptoms of stress cases and 144 matched controls were included in the analysis. Meaningfully high symptoms of anxiety were defined with a score of 6 points or greater on the phobic anxiety subscale of the Crown-Crisp index. We found that the PM_2.5 effect perceived by the case group was significantly higher than the control group, and the PM_2.5 exposure of the case group was also significantly higher than that of the control group. Binary logistic regression showed that for each increase in unit of PM_2.5 exposure, the risk of pregnant women suffering from high mental stress increased by 13.76% (95 %CI: 8.26-19.53%). Through path analysis modeling, we found that in the case group, perceived indoor attributions not only had a direct impact on mental stress (p < 0.001), but also played a key mediating role in the impact of average daily dose of PM_2.5 on mental stress (p < 0.001). The high level of mental stress is not only affected by objective exposure, but also by subjective perceptions in the case group. Considering the significant effect of PM_2.5 exposure on mental stress, pregnant women are recommended to spend appropriate amounts of time outdoors during clean air days. In addition, the mediating role of risk perception cannot be ignored. It is necessary to reassure pregnant women not to become overly concerned about the risk of PM_2.5 pollution and reduce their psychological burden.

Indoor Particulate Matter in Urban Households: Sources, Pathways, Characteristics, Health Effects, and Exposure Mitigation

Particulate matter (PM) is a complex mixture of solid particles and liquid droplets suspended in the air with varying size, shape, and chemical composition which intensifies significant concern due to severe health effects. Based on the well-established human health effects of outdoor PM, health-based standards for outdoor air have been promoted (e.g., the National Ambient Air Quality Standards formulated by the U.S.). Due to the exchange of indoor and outdoor air, the chemical composition of indoor particulate matter is related to the sources and components of outdoor PM. However, PM in the indoor environment has the potential to exceed outdoor PM levels. Indoor PM includes particles of outdoor origin that drift indoors and particles that originate from indoor activities, which include cooking, fireplaces, smoking, fuel combustion for heating, human activities, and burning incense. Indoor PM can be enriched with inorganic and organic contaminants, including toxic heavy metals and carcinogenic volatile organic compounds. As a potential health hazard, indoor exposure to PM has received increased attention in recent years because people spend most of their time indoors. In addition, as the quantity, quality, and scope of the research have expanded, it is necessary to conduct a systematic review of indoor PM. This review discusses the sources, pathways, characteristics, health effects, and exposure mitigation of indoor PM. Practical solutions and steps to reduce exposure to indoor PM are also discussed.

Housing, health and energy: a characterisation of risks and priorities across Delhi's diverse settlements

Improved housing has the potential to advance health and contribute to the Sustainable Development Goals. Research examining housing, health and energy use in low-income countries is limited; understanding these connections is vital to inform interventions for healthy sustainable human settlements. This paper investigates the low-income setting of Delhi, where rapid urbanisation, a varied climate, high pollution levels, and a wide variation in housing quality could result in significant energy use and health risks. Drawing on approaches from health and the built environment and existing data and literature, a characterisation of energy use and health risks for Delhi's housing stock is completed. Four broad settlement types were used to classify Delhi housing and energy use calculations and health risk assessment were performed for each variant. Energy use is estimated to be nearly two times higher per household among planned housing compared with other settlement types. Health risks, however, are found to be largest within informal slum settlements, with important contributions from heat and particulate matter across all settlements. This paper highlights intervention priorities and outlines the need for extensive further research, particularly through data gathering, to establish evidence to accelerate achieving healthy, sustainable and equitable housing in Delhi.

Exposure to mosquito coil and biomass fuel smoke and respiratory health in rural Tamil Nadu, India

BACKGROUND

Mosquito coil smoke, along with biomass fuel smoke, are sources of indoor air pollution. Biomass fuel smoke has been studied as a risk factor for poor respiratory outcomes. However, in an Indian context, few studies examine the effect of mosquito coil exposure on poor respiratory outcomes at the community level.

OBJECTIVES

To estimate the prevalence of the biomass fuel and mosquito coil use and to determine the association between the use of bio-mass fuel and mosquito coil and poor respiratory health.

METHODS

A cross-sectional survey of 4662 individuals (above the age of 30 years) was conducted using a pre-tested questionnaire. Trained interviewers collected data on current and past use of biomass fuels and mosquito coils, usage practices and respiratory health. We computed proportions for exposure variables namely biomass fuel, mosquito coil use and other covariates. We conducted univariate analysis, followed by multivariate logistic regression.

RESULTS

The prevalence of ever use of biomass fuels was high (wood: 97.9%; cow dung cake: 76.0% and crop residue: 54.4%). Current use of wood, cow dung cake and crop residue was prevalent among 75.7, 24.3 and 30.9% respondents, respectively. Almost 70% of respondents had ever used mosquito coils, whereas 54% were current users. Overall, 5.5% respondents had poor respiratory health either due to chronic bronchitis or asthma. In multivariate analysis, use of combination of all three biomass fuel types (adjusted odds ratio [AOR] 1.69, 95% confidence interval [CI]: 1.13-2.54) and use of mosquito coil more than or equal to 5 days per week (AOR 1.43, 95% CI: 1.04-1.99) were associated with poor respiratory health after adjusting for covariates age, gender, smoking, kitchen type and for each other.

CONCLUSIONS

Use of biomass fuels and mosquito coils was high in the study population and was associated with poor respiratory health. Therefore, mosquito coil smoke should also be considered an important source of indoor air pollution, similar to biomass fuel exposure. Community education about these sources of indoor air pollution and increased coverage of cleaner fuels and alternative mosquito control methods should be the way forward in the rural areas.

The Association Between Ambient PM2.5 Exposure and Anemia Outcomes Among Children Under Five Years of Age in India

Anemia is highly prevalent in India, especially in children. Exposure to ambient fine particulate matter (PM2.5) is a potential risk factor for anemia via. systemic inflammation. Using health data from the National Family and Health Survey 2015-2016, we examined the association between ambient PM2.5 exposure and anemia in children under five across India through district-level ecological and individual-level analyses.

METHODS

The ecological analysis assessed average hemoglobin levels and anemia prevalence (hemoglobin < 11 g/dL considered anemic) by district using multiple linear regression models. The individual-level analysis assessed average individual hemoglobin level and anemia status (yes/no) using generalized linear mixed models to account for clustering by district. Ambient PM2.5 exposure data were derived from the Multiangle Imaging SpectroRadiometer (MISR) level 2 aerosol optical depth (AOD) data and averaged from birth date to date of interview.

RESULTS

The district-level ecological analysis found that, for every 10 μg m-3 increase in ambient PM2.5 exposure, average anemia prevalence increased by 1.90% (95% CI = 1.43, 2.36) and average hemoglobin decreased by 0.07 g/dL (95% CI = 0.09, 0.05). At the individual level, for every 10 μg m-3 increase in ambient PM2.5 exposure, average hemoglobin decreased by 0.14 g/dL (95% CI = 0.12, 0.16). The odds ratio associated with a 10-μg m-3 increase in ambient PM2.5 exposure was 1.09 (95% CI = 1.06, 1.11). There was evidence of effect modification by wealth index, maternal anemia status, and child BMI.

CONCLUSION

Our results suggest that ambient PM2.5 exposure could be linked to anemia in Indian children, although additional research on the underlying biologic mechanisms is needed. Future studies on this association should specifically consider interactions with dietary iron deficiency, maternal anemia status, and child BMI.Keywords: Anemia; Children; Ambient PM2.5 exposure; India; Association.

Cooking, smoking, and stunting: Effects of household air pollution sources on childhood growth in India

This paper investigates the effects of household air pollution (HAP) on child stunting in India using a sample of 206, 898 under-five children from the latest National Family Health Survey (2015-16). Descriptive statistics and multivariate analysis were used to understand the association of stunting by type of cooking fuel, separate kitchen, and indoor smoking in the household. Using clean cooking fuels (CCFs), having a separate kitchen, and being unexposed to smoking can reduce the prevalence of stunting by 4%, 1%, and 1%, respectively, from the current prevalence of stunting (38%). The probability of childhood stunting among children living in households using unclean cooking fuel (UCF) was significantly higher (OR-1.16; 95% CI: 1.13-1.19) than those living in households using CCF. Findings were similar results in the absence of separate kitchen (OR-1.08; 95% CI: 1.05-1.10) and exposure to environmental tobacco smoke (OR-1.06; 95% CI: 1.04-1.08). Households using UCF had a 16% higher likelihood of stunting, while there was a strong gradient of HAP with stunting after controlling socioeconomic and demographic factors. Therefore, the LPG programs, such as the Pradhan Mantri Ujjwala Yojana, may be crucial to reduce HAP and its adverse impact on stunting, and successively to achieve sustainable development goals.

Carcinogenic effects of indoor black carbon and particulate matters (PM2.5 and PM10) in rural households of India

Biomass is one of the prime domestic energy sources in the kitchens and about 60% of households are still using biomass and kerosene for cooking in India. These traditional cooking practices are incompetent as the use of biomass in traditional cookstove produces an enormous amount of carbonaceous aerosols that lead to indoor and outdoor air pollution. Emissions of various pollutants like black carbon (BC), PM₁₀ and PM_2.5 from burning of biomass cause serious health impacts like respiratory illness, lung cancer, watering of eyes, coughing, asthma and heart problems especially in women due to higher rate of inhalation of these fine particulate matters during the cooking period. Quantification of BC, PM_2.5 and PM₁₀ emissions from a different type of biomass in various types of kitchen arrangements and its associated impacts are poorly examined in India. Hence, daily concentrations of BC, PM_2.5 and PM₁₀ were monitored from different types of biomass user's households during January 2018 to December 2019 to assess indoor air quality by using aethalometer and nephelometer (pDR-1500) in three districts (Sitapur, Patna and Murshidabad) of Indo-Gangetic Plains (IGP) where approximately, 96% of rural families rely on biomass cooking. The highest mass concentrations were observed in biomass user's households and cow-dung cake users due to low calorific value. About 30.13% of PM₁₀ and 35.89% of PM_2.5 data exceeded the national ambient air quality standard on a daily basis in biomass user's households. A cancer risk assessment was also conducted in terms of mass concentration of these pollutants. The lifespan danger from exposure to BC was 4.33 × 10^-7 in indoor for non-ventilated kitchens, 2.63 × 10^-7 in indoor for ventilated kitchens, 3.98 × 10^-7 in outdoor for separated kitchen, 3.22 × 10^-7 for semi-open kitchen and 1.78 × 10^-7 for open kitchen. The vulnerability assessment for cancer mortality under exposure of pollution was estimated to be highest for the age group of more than 50 years whereas lowest for the age group of 0-4 years for all kinds of kitchens in the study area.

Effect of PM10 on pulmonary immune response and fetus development

Despite numerous reports that ambient particulate matter is a key determinant for human health, toxicity data produced based on physicochemical properties of particulate matters is very lack, suggesting lack of scientific evidence for regulation. In this study, we sampled inhalable particulate matters (PM10) in northern Seoul, Korea. PM10 showed atypical- and fiber-type particles with the average size and the surface charge of 1,598.1 ± 128.7 nm and -27.5 ± 2.8, respectively, and various toxic elements were detected in the water extract. On day 90 after the first pulmonary exposure, total cell number dose-dependently increased in the lungs of both sexes of mice. PM10 induced Th1-dominant immune response with pathological changes in both sexes of mice. Meanwhile, composition of total cells and expression of proteins which functions in cell-to-cell communication showed different trends between sexes. Following, male and female mice were mated to identify effects of PM10 to the next generation. PM10 remained in the lung of dams until day 21 after birth, and the levels of IgA and IgE increased in the blood of dams exposed to the maximum dose compared to control. In addition, the interval between births of fetuses, the number of offspring, the neonatal survival rate (day 4 after birth) and the sex ratio seemed to be affected at the maximum dose, and particularly, all offspring from one dam were stillborn. In addition, expression of HIF-1α protein increased in the lung tissue of dams exposed to PM10, and level of hypoxia-related proteins was notably enhanced in PM10-exposed bronchial epithelial cells compared to control. Taken together, we suggest that inhaled PM10 may induce Th1-shifting immune response in the lung, and that it may affect reproduction (fetus development) by causing lung hypoxia. Additionally, we propose that further study is needed to identify particle-size-dependent effects on development of the next generation.

A Systematic Review of Air Quality Sensors, Guidelines, and Measurement Studies for Indoor Air Quality Management

The existence of indoor air pollutants—such as ozone, carbon monoxide, carbon dioxide, sulfur dioxide, nitrogen dioxide, particulate matter, and total volatile organic compounds—is evidently a critical issue for human health. Over the past decade, various international agencies have continually refined and updated the quantitative air quality guidelines and standards in order to meet the requirements for indoor air quality management. This paper first provides a systematic review of the existing air quality guidelines and standards implemented by different agencies, which include the Ambient Air Quality Standards (NAAQS); the World Health Organization (WHO); the Occupational Safety and Health Administration (OSHA); the American Conference of Governmental Industrial Hygienists (ACGIH); the American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE); the National Institute for Occupational Safety and Health (NIOSH); and the California ambient air quality standards (CAAQS). It then adds to this by providing a state-of-art review of the existing low-cost air quality sensor (LCAQS) technologies, and analyzes the corresponding specifications, such as the typical detection range, measurement tolerance or repeatability, data resolution, response time, supply current, and market price. Finally, it briefly reviews a sequence (array) of field measurement studies, which focuses on the technical measurement characteristics and their data analysis approaches.

Mother's education level is associated with anthropometric failure among 3- to 12-year-old rural children in Purba Medinipur, West Bengal, India

Maternal education plays a central role in children's health and nutrition. Living conditions and socioeconomic status are linked with mother's education, which in turn determines the health and development of a child. The Composite Index of Anthropometric Failure (CIAF) is a single indicator that reflects overall rate of three conventional indices of undernutrition: underweight, stunting and wasting. The study was undertaken among 621 rural Bengalee children (308 boys and 313 girls) aged 3-12 years from the Purba Medinipur district of West Bengal, India. Height (cm) and weight (kg) were recorded and NCHS standard values used to calculate z-scores (<-2SD). The same data were used to calculate CIAF as an indicator of 'anthropometric failure' (AF) or undernutrition. The prevalence of AF among the children was 59.40%. Chi-squared analysis was employed to evaluate the significance of differences in the prevalence of CIAF between the sexes and the association between nutritional indicators and socioeconomic parameters in the two sexes. Multiple binary logistic regression (MBLR) analyses (including the forward stepwise method) were also performed. Odds ratios with 95% confidence intervals were used to assess the risk of having AF. Results showed that mother's education was significantly associated with undernutrition (AF) controlling for the other factors considered. A very high prevalence of undernutrition is persisting in this region of India despite national nutritional supplementation programmes being operational. More attention to the improvement of living conditions and hygiene, and more particularly the education of women, in this population might be effective in attaining improved child growth and health.

The effects of climate change on respiratory allergy and asthma induced by pollen and mold allergens

The impact of climate change on the environment, biosphere, and biodiversity has become more evident in the recent years. Human activities have increased atmospheric concentrations of carbon dioxide (CO₂ ) and other greenhouse gases. Change in climate and the correlated global warming affects the quantity, intensity, and frequency of precipitation type as well as the frequency of extreme events such as heat waves, droughts, thunderstorms, floods, and hurricanes. Respiratory health can be particularly affected by climate change, which contributes to the development of allergic respiratory diseases and asthma. Pollen and mold allergens are able to trigger the release of pro-inflammatory and immunomodulatory mediators that accelerate the onset the IgE-mediated sensitization and of allergy. Allergy to pollen and pollen season at its beginning, in duration and intensity are altered by climate change. Studies showed that plants exhibit enhanced photosynthesis and reproductive effects and produce more pollen as a response to high atmospheric levels of carbon dioxide (CO₂ ). Mold proliferation is increased by floods and rainy storms are responsible for severe asthma. Pollen and mold allergy is generally used to evaluate the interrelation between air pollution and allergic respiratory diseases, such as rhinitis and asthma. Thunderstorms during pollen seasons can cause exacerbation of respiratory allergy and asthma in patients with hay fever. A similar phenomenon is observed for molds. Measures to reduce greenhouse gas emissions can have positive health benefits.

Household air pollution in India and respiratory diseases: current status and future directions

PURPOSE OF REVIEW

Combustion of solid cooking fuels employed by more than 3 billion people globally, contributes to approximately one third of ambient air pollution. In the recent past, the issue has drawn global attention because of its threat to the health of rural communities, particularly women and children. This review is focused on the evidence from India on effects of household air pollution (HAP) on respiratory health and interventions to replace the solid fuels.

RECENT FINDINGS

HAP exposure is a major risk factor for increased respiratory symptoms, respiratory infections, and chronic obstructive pulmonary disease. In most studies, the odds ratio for the risk of development of respiratory disorders is more than one in HAP exposed individuals. HAP is also associated with increased risk of tuberculosis, asthma, mortality from cardio-respiratory illnesses, and nonrespiratory problems such as adverse pregnancy outcomes, prematurity, and low birth weight.

SUMMARY

Household air pollution is a common but preventable risk factor for respiratory diseases. Replacement of solid cooking fuels with clean fuels such as LPG gas as exemplified by the 'Ujjwala' program of India is likely to be most effective intervention to reduce the HAP related disease burden.

The correlation between atmospheric visibility and influenza in Wuxi city, China

Influenza is an acute respiratory infectious disease that poses a threat to public health. We assessed the association between atmospheric visibility and influenza and influenza-like illness (ILI) in Wuxi city, China.Daily meteorological data, ILI activity, and influenza virus infection rates were collected between 31 December 2012 and 31 December 2017. A distributed lag non-linear model (DLNM) was used to analyze the exposure-lag-response of ILI and influenza activity and daily average visibility.A total of 12,800 cases were detected; 1046 cases (8.17%) were of Flu-A and 527 (4.12%) were of Flu-B infection. Our analysis suggested a non-linear relationship between atmospheric visibility and influenza: U-shaped for ILI, and L-shaped for Flu-A and Flu-B. Comparing low visibility (2.5 km) to ILI cases, the risk appeared between day 1 and day 2. For Flu-A, the risk appeared between days 5 and 9, whereas for Flu-B, the risk effect was much stronger and had a longer reaction delay, staying above zero until day 9. The protective effects of high visibility (14 km) on ILI and Flu-B occurred the same day or one day later. However, we found no association between high visibility and Flu-A.In conclusion, our study contributes novel evidence for the effects of atmospheric visibility on influenza. These findings are important for the development of influenza surveillance and early warning systems in Wuxi city.

Socio-economic Correlates and Spatial Heterogeneity in the Prevalence of Asthma among Young Women in India

Background

Asthma is one of the leading causes of disease burden when measured in terms of disability adjusted life years, despite low prevalence of self-reported cases among young women. This paper deals with the meso-scale correlates and spatial heterogeneity in the prevalence of self-reported Asthma across 640 districts in India, using a nationally representative sample of 699,686 women aged 15–49 years from all 36 States/UTs under NFHS-4 (2015–16).

Methods

Analytical methods used in this paper include multivariate logistic regression to examine the adjusted effects of various independent variables on self-reported Asthma and poor-rich ratios (PRR) and concentration index (CI) to understand the economic inequalities in the prevalence of Asthma. For the spatial analysis in the prevalence of Asthma, univariate and bivariate local Moran’s I statistic have been computed in addition to measure of spatial autocorrelation and auto regression using spatial error and spatial lag models.

Results

Results highlight that women’s education was an important marker to the prevalence of Asthma. Smoking tobacco in any form among women were significantly more likely to suffer from Asthma. The prevalence of Asthma was further aggravated among women from the households without a separate room for kitchen, as well as those using unclean fuel for cooking. The poor-rich ratio in the prevalence of Asthma across various States/UTs in India depict inherent inequality. An analysis of spatial clustering in the prevalence of Asthma based on spatial autocorrelation portrays that Moran’s I values were significant for improved source of drinking water, clean fuel used for cooking, and household environment. When spatial weights are taken into consideration, the autoregression model noticeably becomes stronger in predicting the prevalence of Asthma.

Conclusions

Any programmatic effort to curb the prevalence of Asthma through vertical interventions may hinge around the use of clean fuel, poverty, and lifestyle of subjects, irrespective of urban-rural place of their residence, environmental and ecological factors.

Household cooking fuel use and its health effects among rural women in southern India-A cross-sectional study

The use of biomass fuel is associated with the deterioration of human health and women are more likely to develop health conditions due to their exposure to indoor air pollution during cooking. This study was conducted to assess the pattern of fuel used for cooking in households as well as to determine the association between the types of fuel used with respect to socio-demographic characteristics and health status of women. A community based cross-sectional survey was conducted between August 2016 and September 2018 in four rural areas and one semi-urban area of Udupi district, Karnataka, India. The study comprised 587 families including 632 women. A pre-tested semi-structured questionnaire was used to collect data on the type of fuel as well as self-reported health conditions. Overall, 72.5% of the families used biomass, where 67.2% families were currently using both biomass and liquefied petroleum gas while only biomass was used in 5.3% of the families for cooking. Among women, being ever exposed to biomass fuel was significantly associated with their age, literacy level, occupation and socio-economic status (p < 0.001). Those who were exposed to biomass fuel showed a significant association with self-reported ophthalmic (AOR = 3.85; 95% CI: 1.79–8.29), respiratory (OR = 5.04; 95% CI: 2.52–10.07), cardiovascular (OR = 6.07; 95% CI: 1.88–19.67), dermatological symptoms /conditions (AOR = 3.67; 95% CI: 1.07–12.55) and history of adverse obstetric outcomes (AOR = 2.45; 95% CI: 1.08–5.57). A positive trend was observed between cumulative exposure to biomass in hour-years and various self-reported health symptoms/conditions (p < 0.001). It was observed that more than two-thirds of women using biomass fuel for cooking were positively associated with self-reported health symptoms. Further longitudinal studies are essential to determine the level of harmful air pollutants in household environment and its association with various health conditions among women in this region.

Does use of solid fuels for cooking contribute to childhood stunting? A longitudinal data analysis from low- and middle-income countries

Using longitudinal data from the first and second waves of the Young Lives Study (YLS) in Ethiopia, India (Andhra Pradesh), Peru and Vietnam, conducted in 2002 and 2006–07, and a repeated measures mixed model, this study examined the effect of the use of solid fuels for cooking on childhood stunting among children aged 5–76 months. The analysis showed that in all four populations, the average height-for-age z-score (HAZ score) was much lower among children living in households using solid fuels than among children in households using cleaner fuels for cooking. The average HAZ score was lower among children living in households that used solid fuels in both waves of the YLS compared with those whose households used solid fuels in only one of the two waves. A significant reduction was noted in the average HAZ score between the two waves in all countries except Ethiopia. The results of the repeated measures mixed model suggest that household use of solid fuels was significantly associated with lower HAZ scores in all populations, except Ethiopia. The findings also indicate that the reduction in the HAZ scores between waves 1 and 2 was not statistically significant by the type of cooking fuel after controlling for potential confounding factors. The study provides further evidence of a strong association between household use of solid fuels and childhood stunting in low- and middle-income countries using longitudinal data. The findings highlight the need to reduce exposure to smoke from the combustion of solid fuels, by shifting households to cleaner cooking fuels, where feasible, by providing cooking stoves with improved combustion of solid fuels and improved venting, and by designing and implementing public information campaigns to inform people about the health risks of exposure to cooking smoke.

Air Pollution in a Nationally Representative Sample: Findings from the National Adult Tobacco Survey of Lao PDR

In Southeast Asia, household air pollution (HAP) from solid fuel use is the leading cause of disability-adjusted life years (DALYs), a risk which is compounded by exposure to other sources of indoor and outdoor air pollution including secondhand tobacco smoke (SHS). The purpose of this study was to measure the individual and combined prevalence of exposure to household and community sources of air pollution in a national sample of adults in Lao PDR. We analyzed data from the 2012 National Adult Tobacco Survey (NATSL) of Lao PDR-a multi-stage stratified cluster sample of 9706 subjects from 2822 households located in all 17 provinces. Our findings indicate a high prevalence of exposure to household air pollution from cooking fires (78%) and SHS exposure in the home (74.5%). More than a third (32.8%) reported exposure to both inside the home. Exposure to outdoor sources of smoke from cooking, trash, and crop fires was substantial (30.1% to 56.0%). The aggregation of exposures from multiple sources of household air pollution raises the need for initiatives that establish programmatic linkages in the health, environmental, and agricultural sectors to provide a comprehensive strategy to reduce risk factors for respiratory disease in Lao PDR and the region.

South Asian Health: Inflammation, Infection, Exposure, and the Human Microbiome

This paper presents the results of the literature review conducted for the working group topic on inflammation, infection, exposure, and the human microbiome. Infection and chronic inflammation can elevate risk for cardiovascular disease and cancer. Environmental exposures common among South Asian (SA) subgroups, such as arsenic exposure among Bangladeshis and particulate matter air pollution among taxi drivers, also pose risks. This review explores the effects of exposure to arsenic and particulate matter, as well as other infections common among SAs, including human papillomavirus (HPV) and hepatitis B/C infection. Emerging research on the human microbiome, and the effect of microbiome changes on obesity and diabetes risk among SAs are also explored.

Response of Global Air Pollutant Emissions to Climate Change and Its Potential Effects on Human Life Expectancy Loss

Geographical environment and climate change are basic factors for spatial fluctuations in the global distribution of air pollutants. Against the background of global climate change, further investigation is needed on how meteorological characteristics and complex geographical environment variations can drive spatial air pollution variations. This study analyzed the response of air pollutant emissions to climate change and the potential effects of air pollutant emissions on human health by integrating the air pollutant emission simulation model (GAINS) with 3 versions and CMIP5. The mechanism by which meteorological characteristics and geographical matrices can drive air pollution based on monitoring data at the site-scale was also examined. We found the total global emission of major air pollutants increased 1.32 times during 1970–2010. Air pollutant emissions will increase 2.89% and 4.11% in China and developed countries when the scenario of only maximum technically feasible reductions is performed (V4a) during 2020–2050. However, it will decrease 19.33% and 6.78% respectively by taking the V5a climate scenario into consideration, and precipitation variation will contribute more to such change, especially in China. Locally, the air circulation mode that is dominated by local geographical matrices and meteorological characteristics jointly affect the dilution and diffusion of air pollutants. Therefore, natural conditions, such as climate changes, meteorological characteristics and topography, play an important role in spatial air pollutant emissions and fluctuations, and must be given more attention in the processes of air pollution control policy making.

Modeling the Impact of an Indoor Air Filter on Air Pollution Exposure Reduction and Associated Mortality in Urban Delhi Household

Indoor exposure to fine particulate matter (PM_2.5) is a prominent health concern. However, few studies have examined the effectiveness of long-term use of indoor air filters for reduction of PM_2.5 exposure and associated decrease in adverse health impacts in urban India. We conducted 20 simulations of yearlong personal exposure to PM_2.5 in urban Delhi using the National Institute of Standards and Technology's CONTAM program (NIST, Gaithersburg, MD, USA). Simulation scenarios were developed to examine different air filter efficiencies, use schedules, and the influence of a smoker at home. We quantified associated mortality reductions with Household Air Pollution Intervention Tool (HAPIT, University of California, Berkeley, CA, USA). Without an air filter, we estimated an annual mean PM_2.5 personal exposure of 103 µg/m³ (95% Confidence Interval (CI): 93, 112) and 137 µg/m³ (95% CI: 125, 149) for households without and with a smoker, respectively. All day use of a high-efficiency particle air (HEPA) filter would reduce personal PM_2.5 exposure to 29 µg/m³ and 30 µg/m³, respectively. The reduced personal PM_2.5 exposure from air filter use is associated with 8-37% reduction in mortality attributable to PM_2.5 pollution in Delhi. The findings of this study indicate that air filter may provide significant improvements in indoor air quality and result in health benefits.

Characteristics of indoor air pollution and estimation of respiratory dosage under varied fuel-type and kitchen-type in the rural areas of Telangana state in India

Indoor Air Pollution (IAP) is one of the top environmental risks in developing countries including India, with more than a million deaths annually, predominantly through Particulate Matter (PM) exposure. The current study deals with the measurement of PM concentrations in rural households under varied fuel and kitchen-types, evaluation of the indoor air pollution (IAP) characteristics and estimation of respiratory dosage for the different subjects (women, young children and the elderly). Monitoring of particulate matter (PM) was carried out during summer, monsoon and winter season with biomass, LPG and combine of biomass and LPG being used as fuel for cooking. Furthermore, different types of indoor kitchens (with partition and without partition) and outdoor kitchens (separate enclose kitchen and open kitchen) were also considered as kitchen type along with fuel are two crucial factors contributing to IAP. Deposition fractions were calculated using Multiple Particle Path Dosimetry (MPPD) to study the deposition patterns in different parts of the human respiratory tract (HRT) - head, tracheobronchial and pulmonary for women, young children and the elderly people. Dosage of particulate matter was calculated by inputting the recorded PM measurements, a comparison made for biomass-LPG and dosage intensification due to the kitchen-type presented. While the biomass households exhibited high levels of dosage (1181.4 to 5891.7 μg) against the LPG households (89.9 to 811.2 μg), the indoor kitchen types exhibited a maximum intensification of 10.6 times than outdoor kitchens with the same fuel. This study not only establishes the IAP characteristics but also quantifies the role of fuel-type and kitchen-type in IAP. The study also indicates various measures that could be deployed to reduce dosage and thus minimize the health risks.

Parental knowledge and common practices regarding acute respiratory infections in children admitted in a hospital in rural setting

Context:

In developing countries, there is paucity of data regarding knowledge and practices of parents regarding acute respiratory infections (ARIs).

Aims:

The present study was undertaken to study the knowledge and practices of parents for ARIs.

Settings and Design:

This was a prospective, cross-sectional study conducted over period of 3 months in pediatric ward of a tertiary care teaching hospital.

Subjects and Methods:

All the children admitted in pediatrics ward with complaints of ARI were included in the study.

Statistical Analysis Used:

Statistical analysis was carried out by using Statistical Package for Social Sciences software version 20.

Results:

A total of 1,752 children were enrolled in the study out of which 885 (50.51%) were males and 867 (49.49%) were females. Only 42.6% of parents answered correct answers about the proper use of antibiotics for children with ARI. Most of the caregivers (58.4%) had poor knowledge about incomplete immunization as a risk factor for developing diseases like diphtheria and pertussis. Majority of caregivers (66.3%) practice home remedies by themselves.

Conclusion:

The knowledge of caregivers/parents regarding symptoms, risk factors, and complications of ARI was adequate. Better awareness is needed for safe use of antibiotics, and caregivers shall be encouraged to minimize indoor air pollution. More awareness is required for discouraging the practice of visiting quacks as it can lead to serious complications in the child.

Applying Integrated Exposure-Response Functions to PM2.5 Pollution in India

Fine particulate matter (PM2.5, diameter ≤2.5 μm) is implicated as the most health-damaging air pollutant. Large cohort studies of chronic exposure to PM2.5 and mortality risk are largely confined to areas with low to moderate ambient PM2.5 concentrations and posit log-linear exposure-response functions. However, levels of PM2.5 in developing countries such as India are typically much higher, causing unknown health effects. Integrated exposure-response functions for high PM2.5 exposures encompassing risk estimates from ambient air, secondhand smoke, and active smoking exposures have been posited. We apply these functions to estimate the future cause-specific mortality risks associated with population-weighted ambient PM2.5 exposures in India in 2030 using Greenhouse Gas-Air Pollution Interactions and Synergies (GAINS) model projections. The loss in statistical life expectancy (SLE) is calculated based on risk estimates and baseline mortality rates. Losses in SLE are aggregated and weighted using national age-adjusted, cause-specific mortality rates. 2030 PM2.5 pollution in India reaches an annual mean of 74 μg/m³, nearly eight times the corresponding World Health Organization air quality guideline. The national average loss in SLE is 32.5 months (95% Confidence Interval (CI): 29.7⁻35.2, regional range: 8.5⁻42.0), compared to an average of 53.7 months (95% CI: 46.3⁻61.1) using methods currently applied in GAINS. Results indicate wide regional variation in health impacts, and these methods may still underestimate the total health burden caused by PM2.5 exposures due to model assumptions on minimum age thresholds of pollution effects and a limited subset of health endpoints analyzed. Application of the revised exposure-response functions suggests that the most polluted areas in India will reap major health benefits only with substantial improvements in air quality.

Experiences with the Mass Distribution of LPG Stoves in Rural Communities of Ghana

Household air pollution (HAP) is a leading cause of morbidity and mortality worldwide. To limit HAP exposure and environmental degradation from biomass fuel use, the Government of Ghana promotes liquefied petroleum gas (LPG) use in rural Ghana via the Rural LPG program (RLP). We assessed the experiences of the RLP in 2015, 2 years after its launch. A mixed methods approach was used involving Focus Group Discussions (19) and in-depth interviews (25). In addition, a survey questionnaire was administered to elicit socio-demographic characteristics, household cooking practices and stove use patterns of 200 randomly selected respondents. At about 9 months after LPG acquisition, < 5% of LPG beneficiaries used their stoves. Some of the reasons ascribed to the low usage of the LPG cookstoves were financial constraints, distance to LPG filling point and fear of burns. Community members appreciate the convenience of using LPG. Our results underscore a need for innovative funding mechanisms contextualized within an overall economic empowerment of rural folks to encourage sustained LPG use. It emphasizes the need for innovative accessibility interventions. This could include establishing new LPG filling stations in RLP beneficiary districts to overcome the barriers to sustained LPG use.

Change in household fuels dominates the decrease in PM2.5 exposure and premature mortality in China in 2005-2015

The Chinese government has taken efforts to tackle the nation’s severe ambient fine particle (PM_2.5) pollution. Our results suggest that reduced household solid-fuel consumption was the leading contributor to the rapid decrease in the integrated exposure to ambient and household PM_2.5 pollution during 2005–2015, even though there was no explicit household control policy. In contrast, the emission reductions from power plants, industry, and transportation contributed much less to the decrease of integrated exposure. Clean household heating fuels have become part of recent control policies in northern China, but such policy would be strengthened if extended to heating and cooking countrywide since shift of the remaining household solid fuels to clean fuels could additionally avoid an estimated half-million premature deaths annually.

To tackle the severe fine particle (PM_2.5) pollution in China, the government has implemented stringent control policies mainly on power plants, industry, and transportation since 2005, but estimates of the effectiveness of the policy and the temporal trends in health impacts are subject to large uncertainties. By adopting an integrated approach that combines chemical transport simulation, ambient/household exposure evaluation, and health-impact assessment, we find that the integrated population-weighted exposure to PM_2.5 (IPWE) decreased by 47% (95% confidence interval, 37–55%) from 2005 [180 (146–219) μg/m³] to 2015 [96 (83–111) μg/m³]. Unexpectedly, 90% (86–93%) of such reduction is attributed to reduced household solid-fuel use, primarily resulting from rapid urbanization and improved incomes rather than specific control policies. The IPWE due to household fuels for both cooking and heating decreased, but the impact of cooking is significantly larger. The reduced household-related IPWE is estimated to avoid 0.40 (0.25–0.57) million premature deaths annually, accounting for 33% of the PM_2.5-induced mortality in 2015. The IPWE would be further reduced by 63% (57–68%) if the remaining household solid fuels were replaced by clean fuels, which would avoid an additional 0.51 (0.40–0.64) million premature deaths. Such a transition to clean fuels, especially for heating, requires technology innovation and policy support to overcome the barriers of high cost of distribution systems, as is recently being attempted in the Beijing–Tianjin–Hebei area. We suggest that household-fuel use be more highly prioritized in national control policies, considering its effects on PM_2.5 exposures.

[Prevalence and characteristics of chronic obstructive pulmonary disease in non-smokers]

Objetivo

Conocer el perfil y las características de los enfermos diagnosticados de enfermedad pulmonar obstructiva crónica (EPOC) y que nunca han sido fumadores.

Diseño

Estudio descriptivo transversal.

Emplazamiento

Área Básica de Salud del Pla d’Urgell (Atención Primaria de Lleida, España).

Participantes

Se incluyeron los 512 pacientes mayores de 40 años diagnosticados de EPOC del Área Básica de Salud con una espirometría compatible al inicio del estudio [cociente < 0,7 entre el volumen de espiración forzada en el primer segundo (FEV₁) y la capacidad vital forzada (FVC)].

Mediciones principales

La variable dependiente fue la EPOC en no fumadores y las independientes fueron variables recogidas a partir de la información sobre la historia clínica respiratoria, los factores de riesgo del enfermo y sobre calidad vida. Se diseñó un modelo predictor de padecer EPOC en no fumadores en comparación con los fumadores.

Resultados

El 33,2% de los pacientes EPOC nunca habían sido fumadores y de estos, el 59,4% eran mujeres. La media del FEV₁ de los no fumadores fue de 70,5 (DE = 17,1), superior a los 62,6 (DE = 18,5) en los fumadores/exfumadores (p < 0,001). La cobertura de la vacunación antineumocócica 23V era mejor en los no fumadores (75,3%), p < 0,001. Los EPOC en no fumadores (respecto a los fumadores/exfumadores) eran: mayormente mujeres (OR = 16,46), de mayor edad (OR = 1,1), con mejor FEV₁ (OR = 1,1), mejor percepción de calidad de vida, EuroQoL-5D (OR = 0,8), con menor prevalencia de diabetes (OR = 0,5), menor nivel de estudios (OR = 0,2), y con menos hospitalizaciones previas (OR = 0,3).

Conclusiones

El estudio evidencia una alta proporción de no fumadores en enfermos EPOC. Nuestro trabajo objetiva que las mujeres de mayor edad y con menor gravedad se asociarían a un mayor riesgo de EPOC en no fumadores. Parece indicar que la EPOC en no fumadores aparecería en edades más tardías y sería más leve que la EPOC relacionada con el tabaquismo.

Global estimation of exposure to fine particulate matter (PM2.5) from household air pollution

BACKGROUND

Exposure to household air pollution (HAP) from cooking with dirty fuels is a leading health risk factor within Asia, Africa and Central/South America. The concentration of particulate matter of diameter ≤ 2.5 μm (PM_2.5) is an important metric to evaluate HAP risk, however epidemiological studies have demonstrated significant variation in HAP-PM_2.5 concentrations at household, community and country levels. To quantify the global risk due to HAP exposure, novel estimation methods are needed, as financial and resource constraints render it difficult to monitor exposures in all relevant areas.

METHODS

A Bayesian, hierarchical HAP-PM_2.5 global exposure model was developed using kitchen and female HAP-PM_2.5 exposure data available in peer-reviewed studies from an updated World Health Organization Global HAP database. Cooking environment characteristics were selected using leave-one-out cross validation to predict quantitative HAP-PM_2.5 measurements from 44 studies. Twenty-four hour HAP-PM_2.5 kitchen concentrations and male, female and child exposures were estimated for 106 countries in Asia, Africa and Latin America.

RESULTS

A model incorporating fuel/stove type (traditional wood, improved biomass, coal, dung and gas/electric), urban/rural location, wet/dry season and socio-demographic index resulted in a Bayesian R² of 0.57. Relative to rural kitchens using gas or electricity, the mean global 24-hour HAP-PM_2.5 concentrations were 290 μg/m³ higher (range of regional averages: 110, 880) for traditional stoves, 150 μg/m³ higher (range of regional averages: 50, 290) for improved biomass stoves, 850 μg/m³ higher (range of regional averages: 310, 2600) for animal dung stoves, and 220 μg/m³ higher (range of regional averages: 80, 650) for coal stoves. The modeled global average female/kitchen exposure ratio was 0.40. Average modeled female exposures from cooking with traditional wood stoves were 160 μg/m³ in rural households and 170 μg/m³ in urban households. Average male and child rural area exposures from traditional wood stoves were 120 μg/m³ and 140 μg/m³, respectively; average urban area exposures were identical to average rural exposures among both sub-groups.

CONCLUSIONS

A Bayesian modeling approach was used to generate unique HAP-PM_2.5 kitchen concentrations and personal exposure estimates for all countries, including those with little to no available quantitative HAP-PM_2.5 exposure data. The global exposure model incorporating type of fuel-stove combinations can add specificity and reduce exposure misclassification to enable an improved global HAP risk assessment.

Development of Ahmedabad's Air Information and Response (AIR) Plan to Protect Public Health

Indian cities struggle with some of the highest ambient air pollution levels in the world. While national efforts are building momentum towards concerted action to reduce air pollution, individual cities are taking action on this challenge to protect communities from the many health problems caused by this harmful environmental exposure. In 2017, the city of Ahmedabad launched a regional air pollution monitoring and risk communication project, the Air Information and Response (AIR) Plan. The centerpiece of the plan is an air quality index developed by the Indian Institute of Tropical Meteorology’s System for Air Quality and Weather Forecasting and Research program that summarizes information from 10 new continuous air pollution monitoring stations in the region, each reporting data that can help people avoid harmful exposures and inform policy strategies to achieve cleaner air. This paper focuses on the motivation, development, and implementation of Ahmedabad’s AIR Plan. The project is discussed in terms of its collaborative roots, public health purpose in addressing the grave threat of air pollution (particularly to vulnerable groups), technical aspects in deploying air monitoring technology, and broader goals for the dissemination of an air quality index linked to specific health messages and suggested actions to reduce harmful exposures. The city of Ahmedabad is among the first cities in India where city leaders, state government, and civil society are proactively working together to address the country’s air pollution challenge with a focus on public health. The lessons learned from the development of the AIR Plan serve as a template for other cities aiming to address the heavy burden of air pollution on public health. Effective working relationships are vital since they form the foundation for long-term success and useful knowledge sharing beyond a single city.

A simulation study of the role of cohort forces in mortality patterns

This study uses the micro-simulation method to investigate the role of cohort forces in age-dependent mortality pattern. We test the micro mechanisms for cohort evolution and mortality selection, and how these two biological and demographic forces may interact with epidemiologic transition to shape the cohort age-dependence of mortality pattern in both early- and later-transition countries. We show that cohort evolution is due to the declining rate of mortality acceleration at the individual level, which is associated with lower initial mortality rates but not smaller variance of frailty distribution in later birth cohorts. The steeper slope of mortality acceleration at the population level among later birth cohorts is due to mortality selection mechanism associated with smaller variance of frailty distribution but not lower initial mortality rates. These two forces jointly shape the non-crossover cohort age-dependence of mortality pattern regardless of the differential mechanisms of epidemiologic transition in early- and later-transition countries.

Household air pollution and chronic hypoxia in the placenta of pregnant Nigerian women: A randomized controlled ethanol Cookstove intervention

BACKGROUND

Household air pollution (HAP) is associated with adverse pregnancy outcomes.

OBJECTIVES

Investigate impact of in-utero HAP exposure on placental development and chronic hypoxia.

METHODS

Markers of chronic placental hypoxia [Hofbauer cells (HBC), syncytial knots (SK), chorionic vascular density (cVD) and hypoxia-inducible factor (HIF)] were stained by hematoxylin-eosin and/or immunohistochemically in placenta samples collected from firewood-/kerosene-users (A,n=16), and ethanol-users (B,n=20) that participated in a randomized controlled intervention trial in Ibadan, Nigeria. A third group of non-smoking and presumed natural gas-using Chicago women (C,n=12) were included in this exploratory pilot to assess for possible differences in placenta histology between similar racial groups. All patients had uncomplicated pregnancies and delivered at term.

RESULTS

HBC, SK and cVD were significantly increased among firewood-/kerosene-users compared to ethanol-users and natural gas-using Chicago women (HBC medians 5.5, 3.5, and 2.0, respectively; SK means 55.6, 41.8 and 30.1; cVD means 8.8, 6.2, and 5.2; all p<0.01). HIF expression was significantly higher in Group A compared to B and C (all p<0.001).

CONCLUSIONS

In-utero exposure to HAP is associated with pathologic changes and HIF expression consistent with chronic hypoxia in placenta of firewood/kerosene-users compared to ethanol-users with less HAP exposure and Chicago women with no presumed HAP exposure. Presence of chronic hypoxic signature in placenta of women exposed to HAP has implications for adverse pregnancy complications and future growth and development of the young children. Future larger studies need to focus on HAP exposure and placental disorders like preeclampsia and long-term health impact of in-utero exposure to HAP.

Status of indoor air pollution (IAP) through particulate matter (PM) emissions and associated health concerns in South Asia

Exposure to particulate emissions poses a variety of public health concerns worldwide, specifically in developing countries. This review summarized the documented studies on indoor particulate matter (PM) emissions and their major health concerns in South Asia. Reviewed literature illustrated the alarming levels of indoor air pollution (IAP) in India, Pakistan, Nepal, and Bangladesh, while Sri Lanka and Bhutan are confronted with relatively lower levels, albeit not safe. To our knowledge, data on this issue are absent from Afghanistan and Maldives. We found that the reported levels of PM₁₀ and PM_2.5 in Nepal, Pakistan, Bangladesh, and India were 2-65, 3-30, 4-22, 2-28 and 1-139, 2-180, 3-77, 1-40 fold higher than WHO standards for indoor PM₁₀ (50 μg/m³) and PM_2.5 (25 μg/m³), respectively. Regarding IAP-mediated health concerns, mortality rates and incidences of respiratory and non-respiratory diseases were increasing with alarming rates, specifically in India, Pakistan, Nepal, and Bangladesh. The major cause might be the reliance of approximately 80% population on conventional biomass burning in the region. Current review also highlighted the prospects of IAP reduction strategies, which in future can help to improve the status of indoor air quality and public health in South Asia.

Emission reduction potentials of improved cookstoves and their issues in adoption: An Indian outlook

Biomass as a fuel for cooking is a common practice in rural India, and about 700 million people use traditional stoves to meet their energy demand. However, the thermal and the combustion efficiencies of these stoves are very low, leading to an inefficient use of biomass, and also, resulting in significant indoor air pollution. Research development has however led to the development of some improved stoves viz., natural draft and forced draft for both domestic as well as large scale cooking applications and government is trying to promote them. Forced draft stoves using processed biomass fuels (pellets) have received more prominence due to their superior performance, however, higher initial cost and limited fuel distribution networks have remained the key challenges. Improved natural draft stoves too have gained attention for being relatively inexpensive, and they are more likely to hit the rural households. In this paper, we have examined the environmental benefits obtained by the use of improved stoves for two important scenarios: traditional stoves are replaced by (i)improved natural draft stoves and, (ii) by improved natural draft as well as forced draft stoves. In the best case scenario (case ii), i.e., by shifting 111 million households who currently use wood to the forced draft stoves, and another 45 million households who are dependent on dung cake and agro residues to the improved natural draft stoves, the emission reduction that can be achieved are as follows: particulate matter (PM) 875 kT, black carbon (BC) 229 kT, organic carbon (OC) 525 kT, methane (CH₄)1178 kT and non methane hydrocarbon (NMHC) of 564 kT. With the promotion of only natural draft improved stoves, the total reductions would be ∼12% lower than the combinational promotion. The CO₂ equivalent reduction is estimated to be ∼70-80 MT per year.