Household Air Pollution Exposure Research Articles

Nepal Family Cohort study: a study protocol

IntroductionThe Nepal Family Cohort study uses a life course epidemiological approach to collect comprehensive data on children’s and their parents’ environmental, behavioural and metabolic risk factors. These factors can affect...

Air pollution and under-5 child mortality: linking satellite and IPUMS-DHS data across 41 countries in South Asia and Sub-Saharan Africa

BackgroundDespite progress, under-five mortality remains high, especially in Sub-Saharan Africa and South Asia, where around 13,400 children die daily. Environmental pollutants, including PM2.5 from outdoor air and household air pollution, significantly contribute to these preventable deaths.MethodsThis cross-country study combined satellite data with 113 surveys from the IPUMS-DHS dataset (1998–2019) to examine under-five child mortality in 41 developing countries. The integration of Global Annual Particulate Matter with a diameter of 2.5 micrometres or less (PM2.5) Grids from Socioeconomic Data and Applications Center (SEDAC) and geospatial data from the DHS Program enabled a focused analysis of the association between indoor and outdoor air pollution, particularly PM2.5, and child mortality rates using both logistic and multilevel logistic regression models, as well as estimating Population Attributable Fractions (PAF) to quantify the mortality burden attributable to these pollutants.ResultsOutdoor air pollution, measured by a one standard deviation increase in PM2.5, significantly increased the risk of child mortality (Odds Ratio [OR]: 1.14; 95% Confidence Interval [CI]: 1.10–1.18; p < 0.001). Moderate and high household air pollution exposure also heightened this risk, with increases of 37% (OR: 1.37; 95% CI: 1.24–1.53; p < 0.001) and 40% (OR: 1.40; 95% CI: 1.26–1.56; p < 0.001), respectively, compared to no exposure. Multilevel models (Models 5a and 10a) produced similar estimates to standard logistic regression, indicating robust associations. Additionally, Population Attributable Fraction analysis revealed that approximately 11.9% of under-five mortality could be prevented by reducing ambient PM2.5 exposure and 12.0% by mitigating household air pollution. The interaction between indoor and outdoor pollution revealed complex dynamics, with moderate and high household exposure associated with a reduction in mortality risk when combined with PM2.5. Geographical disparities were observed, with stronger correlations between outdoor air pollution and child mortality in Africa compared to Asia, and more pronounced impacts in low-income countries. However, household air pollution had stronger association with child mortality in Africa and lower- and middle-income countries.ConclusionsOur findings could serve as a guide for policy development aimed at reducing under-five mortality, ultimately contributing to the attainment of the Sustainable Development Goal (SDGs).

Mitigating household air pollution exposure through kitchen renovation

Globally, over three billion people rely on traditional solid fuels for cooking and heating, leading to significant household air pollution and critical public health concerns. While transitioning to clean energy carriers faces challenges of accessibility and affordability—especially among low-income, rural populations—alternative strategies like kitchen layout modifications and the use of ventilation fans may effectively reduce exposure to pollutants. Here, we analyze factors influencing the adoption of separated kitchens and mechanical ventilation and evaluate changes in human exposure to PM2.5 under different kitchen renovation scenarios by conducting a nationwide survey of household kitchen characteristics in rural China. We found that although 82% of rural households have kitchens separated from other rooms, only 34% use mechanical ventilation. The adoption of ventilation fans is significantly influenced by income and education levels. We estimate that widespread implementation of ventilation fans and separated kitchen designs could prevent approximately 67400 premature deaths annually, resulting in a health benefit of about USD 19 billion per year—substantially exceeding the costs involved. These findings suggest that cost-effective kitchen renovations offer enormous potential for substantial health benefits and present a practical solution compared to the challenges of clean energy transitions in rural areas.

Household air pollution and respiratory health in Africa: persistent risk and unchanged health burdens.

Despite evidence emerging from the Global Burden of Disease studies that biomass use and household air pollution are declining globally, with important positive health impacts for households in low- and middle-income countries, these trends have not been equally documented in African countries. This review describes the state of household air pollution exposure and its relationship with respiratory disease in Africa. African studies on this topic are limited, and generally focus on respiratory infections. Most evidence emerge from models based on the Global Burden of Disease data, and from limited individual epidemiological studies across the continent. More than 80% of the African population is exposed to household air pollution. Women and children continue to bear the substantial burden of exposure. Evidence from limited exposure-response studies strongly points to household air pollution being the major driver of acute and chronic respiratory diseases on the continent. Respiratory infections, particularly in children, and other chronic respiratory diseases, are strongly attributable to household air pollution. Elimination of such exposures through interventions such as cleaner fuels and preferably, electricity, is critical to improving respiratory health on the continent.

The association of solid fuel use in households for cooking with elevated blood pressure among reproductive-aged married women in Bangladesh.

Bangladesh is experiencing a rapid increase in hypertension prevalence, particularly in socio-economically disadvantaged communities. The higher use of solid fuel in these communities could be one of the significant factors contributing to this trend, but evidence supporting this hypothesis is limited in Bangladesh. Therefore, this study aims to investigate the associations of household solid fuel use and its exposure level with systolic and diastolic blood pressure (DBP) and hypertension. We analysed 7,320 women's data from 2017/18 Bangladesh Demographic and Health Survey. We considered three outcome variables: (i) systolic blood pressure (BP) (continuous response), (ii) DBP (continuous response), and (iii) hypertension status (yes, no). Our primary exposures of interest were fuel type (clean vs solid) and the potential level of household air pollution exposure through solid fuel use (unexposed, moderately exposed, and highly exposed). We used a multilevel mixed-effects Poisson regression model with robust variance to determine association between exposure and outcome variables while adjusting for confounders. Of the total respondents analysed, approximately 82% used solid fuel for cooking. The age-standardised prevalence of hypertension was 28%. Respondents using solid fuel were found to be 1.44 times (95% confidence interval [CI], 1.04-1.89) more likely to develop hypertension compared to clean fuel users. Compared to women using clean fuel, the likelihood of hypertension was found to be 1.61 times (95% CI, 1.07-2.20) higher among the moderately exposed group and 1.80 times (95% CI, 1.27-2.32) higher among the highly exposed group. Similar associations were reported for systolic and DBP. The use of solid fuel increases the risk of becoming hypertensive and elevates systolic and DBP. Policies and programmes are necessary to increase awareness of the adverse effects of solid fuel use on health, including hypertension. Efforts should be made to reduce solid fuel use and ensure proper ventilation systems in households where solid fuel is used.

Association between household air pollution due to unclean fuel use and depression among older adults in India: A cross-sectional study.

Depression is a major public concern among older adults. However, limited studies have examined the association of depression and household air pollution (HAP). Therefore, this study examines the association between HAP due to unclean fuel use and depression among older adults in India. Data from Longitudinal Aging Study of India (LASI), wave-1 (2017-18) were used (N = 50,206, ≥50 years). Depression measured by CIDI-SF (Composite International Diagnostic Interview-Short Form) was the outcome variable. Household unclean fuel use was considered as proxy of HAP. Bivariate analyses and multivariate logistic regression were used to fulfil the study objectives. The prevalence of depression was greater among unclean fuel users than clean fuel users (9.6% vs 6.6%). Results showed that household unclean fuel use was associated with higher odds of depression. The interaction analyses showed that females and rural residents were at higher risk of depression due to HAP exposure. Furthermore, household cooking conditions also played an important role in the association between HAP exposure and depression. Unclean fuel use indoors without ventilation and with traditional chullah/stove was associated with higher odds of depression among older adults. The study concludes that exposure to HAP due to unclean fuel use should be considered as a potential risk factor of depression among older adults. Therefore, the study suggests an urgent need to create awareness about negative effects of unclean fuel use on mental health and promote clean fuel usage in households to ensure healthy aging.

Epigenome-wide association study of household air pollution exposure in an area with high lung cancer incidence.

Epigenome-wide association study of household air pollution exposure in an area with high lung cancer incidence.

Household air pollution exposure assessment using low-cost air monitors: results from a large prospective cohort (HEALS-AIR) study in Bangladesh.

Household air pollution exposure assessment using low-cost air monitors: results from a large prospective cohort (HEALS-AIR) study in Bangladesh.

Research Brief: Fuel switching and energy stacking in low-income households in South Africa: A review with recommendations for household air pollution exposure research

Research Brief: Fuel switching and energy stacking in low-income households in South Africa: A review with recommendations for household air pollution exposure research

Association of household air pollution exposure and anemia among pregnant women: Analysis of baseline data from ’Household Air Pollution Intervention Network (HAPIN)’ trial

BackgroundAnemia is common in low- and middle-income countries (LMICs), causing significant health issues and social burdens. Exposure to household air pollution from using biomass fuels for cooking and heating has been associated with anemia, but the exposure–response association has not been studied. ObjectivesWe evaluated the associations between personal exposure to air pollution and both hemoglobin levels and anemia prevalence among pregnant women in a multi-country randomized controlled trial. MethodsWe studied 3,163 pregnant women aged 18–35 years with 9–20 weeks of gestation, recruited as part of the Household Air Pollution Intervention Network (HAPIN) randomized controlled trial in Guatemala, India, Peru, and Rwanda. We assessed 24-hour personal exposures to fine particulate matter (PM2.5), black carbon (BC), and carbon monoxide (CO), and measured hemoglobin levels at baseline (15 ± 3 weeks gestation). Linear and logistic regression models were used to examine the associations of measured pollutants with hemoglobin levels and anemia prevalence, adjusting for confounding. ResultsSingle-pollutant models showed associations of CO with higher hemoglobin levels and lower anemia prevalence. Bipollutant models involving CO and PM2.5 also revealed that an interquartile range (IQR) increase in CO concentrations (2.26 ppm) was associated with higher hemoglobin levels [β = 0.04; 95 % confidence interval (CI): 0.01, 0.07], and a lower odds of anemia prevalence [odds ratios (OR) = 0.90; 95 % CI: 0.83, 0.98]. PM2.5 was inversely related to hemoglobin and positively associated with anemia, but results were not statistically significant at the 0.05 alpha level. County-specific results showed that 3 of 4 countries showed a similar association between CO and hemoglobin. We found no association of BC levels with hemoglobin levels or with anemia prevalence. ConclusionOur findings suggest that exposure to CO is associated with higher hemoglobin and lower anemia prevalence among pregnant women, whereas PM2.5 showed the opposite associations.

Household Air Pollution Interventions to Improve Health in Low- and Middle-Income Countries: An Official American Thoracic Society Research Statement.

Background: An estimated 3 billion people, largely in low- and middle-income countries, rely on unclean fuels for cooking, heating, and lighting to meet household energy needs. The resulting exposure to household air pollution (HAP) is a leading cause of pneumonia, chronic lung disease, and other adverse health effects. In the last decade, randomized controlled trials of clean cooking interventions to reduce HAP have been conducted. We aim to provide guidance on how to interpret the findings of these trials and how they should inform policy makers and practitioners.Methods: We assembled a multidisciplinary working group of international researchers, public health practitioners, and policymakers with expertise in household air pollution from within academia, the American Thoracic Society, funders, nongovernmental organizations, and global organizations, including the World Bank and the World Health Organization. We performed a literature search, convened four sessions via web conference, and developed consensus conclusions and recommendations via the Delphi method.Results: The committee reached consensus on 14 conclusions and recommendations. Although some trials using cleaner-burning biomass stoves or cleaner-cooking fuels have reduced HAP exposure, the committee was divided (with 55% saying no and 45% saying yes) on whether the studied interventions improved measured health outcomes.Conclusions: HAP is associated with adverse health effects in observational studies. However, it remains unclear which household energy interventions reduce exposure, improve health, can be scaled, and are sustainable. Researchers should engage with policy makers and practitioners working to scale cleaner energy solutions to understand and address their information needs.

IJCM_333A: Household Air Pollution Exposure and Autism Spectrum Disorder Outcomes in Children: Insights from the HAPIN India Study

Background: The global public health challenge of household air pollution, stemming from conventional cooking practices and the widespread use of solid fuels, is a critical concern. Exposure to indoor air pollutants has been associated with adverse health outcomes, particularly affecting vulnerable populations like pregnant women and young children. The Household Air Pollution and Neurodevelopment (HAPIN) study addresses this issue through a multicentric randomized controlled trial spanning four diverse countries: Guatemala, India, Peru, and Rwanda. Objectives: The study aims to evaluate the prevalence of autistic spectrum disorder among children residing in HAPIN study site of India. Methodology: A cross-sectional assessment for autism spectrum disorders within the HAPIN cohort was done.365 children aged 2 to 3 years were studied to explore the potential link between household air pollution and autism spectrum disorder (ASD). Household air quality, measuring PM2.5, CO, and black carbon, was assessed using established protocols. Neurodevelopmental outcomes, particularly ASD, was screened using the Modified Checklist for Autism in Toddlers (M-CHAT) in children aged 2 to 3 years, and screened positive children were evaluated by a psychiatrist to diagnose autism spectrum disorder using DSM-5 criteria. Results: There is significant association between exposure to air pollutants (PM2.5, CO, and black carbon) and the diagnosis of autism spectrum disorder (ASD), with a prevalence rate of 5.48%. Conclusion: ASD prevalence rate of 5.48%, underscore the global relevance of the impact of household air pollution on neurodevelopment. Urgent interventions are warranted to mitigate the risk of ASD, particularly for vulnerable populations like pregnant women and young children, emphasizing the imperative for cleaner cooking practices and improved indoor air quality.

Chronic household air pollution and exposure patterns among Himalayan nomads.

Household air pollution (HAP) is a major risk factor of non-communicable diseases, causing millions of premature deaths each year in developing nations. Populations living at high altitudes are particularly vulnerable to HAP and associated health outcomes. This study aims to explore the relationships between activity patterns, HAP, and an HAP biomarker among 100 Himalayan nomadic households during both cooking and heating-only periods. Household CO was monitored in 100 rural homes in Qinghai, China, at 3500 m on the Himalayan Plateau among Himalayan nomads. Carboxyhemoglobin (COHb) was used as a biomarker to assess exposure among 100 male and 100 female heads of household. Linear mixed-effects models were used to explore the relationship between COHb and activity patterns. Cooking periods were associated with 7 times higher household CO concentrations compared with heating periods (94 ± 56 ppm and 13 ± 11 ppm, respectively). Over the three-day biomarker-monitoring period in each house, 99% of subjects had at least one COHb measurement exceeding the WHO safety level of 2%. Cooking was associated with a 32% increase in COHb (p < 0.001). This study on household air pollution (HAP) in high-altitude regions provides important insights into the exposure patterns of nomadic households in Qinghai, China. The study found that cooking is the primary factor influencing acute carbon monoxide (CO) exposure among women, while heating alone is sufficient to elevate CO exposure above WHO guidelines. The results suggest that cooking-only interventions have the potential to reduce HAP exposure among women, but solutions for both cooking and heating may be required to reduce COHb to below WHO guidelines. This study's findings may inform future interventions for fuel and stove selection to reduce HAP and exposure among other populations.

Household air pollution and risk of pulmonary tuberculosis in HIV-Infected adults

BackgroundIn low- and middle-income countries countries, millions of deaths occur annually from household air pollution (HAP), pulmonary tuberculosis (PTB), and HIV-infection. However, it is unknown whether HAP influences PTB risk among people living with HIV-infection.MethodsWe conducted a case-control study among 1,277 HIV-infected adults in Bukavu, eastern Democratic Republic of Congo (February 2018 – March 2019). Cases had current or recent (<5y) PTB (positive sputum smear or Xpert MTB/RIF), controls had no PTB. Daily and lifetime HAP exposure were assessed by questionnaire and, in a random sub-sample (n=270), by 24-hour measurements of personal carbon monoxide (CO) at home. We used multivariable logistic regression to examine the associations between HAP and PTB.ResultsWe recruited 435 cases and 842 controls (median age 41 years, [IQR] 33-50; 76% female). Cases were more likely to be female than male (63% vs 37%). Participants reporting cooking for >3h/day and ≥2 times/day and ≥5 days/week were more likely to have PTB (aOR 1·36; 95%CI 1·06-1·75) than those spending less time in the kitchen. Time-weighted average 24h personal CO exposure was related dose-dependently with the likelihood of having PTB, with aOR 4·64 (95%CI 1·1-20·7) for the highest quintile [12·3-76·2 ppm] compared to the lowest quintile [0·1-1·9 ppm].ConclusionTime spent cooking and personal CO exposure were independently associated with increased risk of PTB among people living with HIV. Considering the high burden of TB-HIV coinfection in the region, effective interventions are required to decrease HAP exposure caused by cooking with biomass among people living with HIV, especially women.

Household air pollution exposure and risk of tuberculosis: a case–control study of women in Lilongwe, Malawi

IntroductionGlobally, 3–4 billion people rely on solid fuels for cooking, and 1 billion use kerosene to light their homes. While household air pollution (HAP) emitted from burning these fuels has...

WO3/Pt photocatalyst supported by a ceramic filter for indoor air purification under visible light irradiation

Household air pollution exposure can lead to various chronic health issues, photocatalytic air purification could improve the indoor air quality.

Carbon Monoxide Exposure and Risk of Cognitive Impairment Among Cooks in Africa

We use air pollution exposure measurements and household survey data from four studies conducted across three countries in sub‐Saharan Africa (SSA) to analyze the association between carbon monoxide (CO) exposure from cooking with biomass and indicators of cognitive impairment. While there is strong evidence on the relationship between ambient air pollution exposure and cognitive impairment from studies in high‐income countries, relatively little research has focused on household air pollution (HAP) in low‐income country settings where risks of HAP exposure are high. This study is the first to our knowledge to focus on the association between HAP exposure (specifically CO exposure) and cognitive impairment across diverse settings in SSA. We use 24‐hour measurements of primary cooks’ exposure to CO across four study sites: urban Zambia (n = 493); urban Malawi (n = 130); rural Malawi (n = 102); and urban Rwanda (n = 2,576). We model the estimated percent carboxyhemoglobin (%COHb) of cooks and map values to a toxicological profile for risk of cognitive impairment. We find that across all study settings, cooks’ average %COHb levels are below levels of daily concern, but that cooks who use charcoal for preparing greater than 40% of meals are more likely to spend additional time at higher levels of risk. For the urban Zambia sample, we compare %COHb and frequency of charcoal use to a series of cognitive test scores and find no consistent relationships between %COHb and cognitive test scores. High levels of daily CO exposure from cooks across SSA highlight the potential for longer‐term negative cognitive (and other) health outcomes motivating additional research and efforts to characterize and mitigate risk.

Household air pollution could make children grow shorter in sub-Saharan Africa; but can households help stem the tide on their own?

Recently, there has been growing research interest in the influence of household air pollution on child health. Despite the increasing advocacy for households to switch from the use of polluting cooking fuels due to climate change and health-related concerns, the practice is still prevalent in Sub-Saharan Africa (SSA). The intensity of household air pollution exposure and its influence on child stunting and wasting of children is an important, but understudied, cause for public health concern. Identifying the health effects of polluting fuels, for instance, could stimulate a speedy transition to clean energy. This study, therefore, examines the association between the intensity of household air pollution exposure and child stunting and wasting of children using data from the most recent demographic and health surveys (DHS) from 33 countries in SSA using linear probability modeling. Results show that high levels of intensity of air pollution within households are associated with increased stunting probability of 2.9% − 3.2%. The findings highlight a potential negligible cost measure households can adopt to limit the intensity of pollution they are exposed to and consequently, to reduce the faltering growth in children.

Biomass smoke exposure and somatic growth among children: The RESPIRE and CRECER prospective cohort studies in rural Guatemala

BackgroundCooking-related biomass smoke is a major source of household air pollution (HAP) and an important health hazard. Prior studies identified associations between HAP exposure and childhood stunting; less is known for underweight and wasting. Few studies had personal HAP measurements. Methods557 households in rural Guatemala were enrolled in the CRECER study, the follow-up study of the RESPIRE randomized intervention trial. They were assigned to three groups that received chimney stoves at different ages of the study children. Multiple personal carbon monoxide (CO) exposure measurements were used as proxies for HAP exposures. Children’s heights and weights were measured from 24 to 60 months of age. Height-for-age z-score (HAZ), weight-for-age z-score (WAZ), and weight-for-height z-score (WHZ) were calculated based on the World Health Organization’s Multicentre Growth Reference Study. HAZ, WAZ, and WHZ below −2 were classified as stunting, underweight, and wasting, respectively. Generalized linear models and mixed effects models were applied. Results541 children had valid anthropometric data, among whom 488 (90.2 %) were stunted, 192 (35.5 %) were underweight, and 2 (0.3 %) were wasted. A 1 ppm higher average CO exposure was associated with a 0.21 lower HAZ (95 % CI: 0.17–0.25), a 0.13 lower WAZ (95 % CI: 0.10–0.17) and a 0.06 lower WHZ (95 % CI: 0.02–0.10).The associations for HAZ were stronger among boys (coefficient = −0.29, 95 % CI: −0.35 – −0.22) than among girls (coefficient = −0.15, 95 % CI: −0.20 – −0.10). A 1 ppm-year higher cumulative CO exposure was associated with a higher risk of moderate stunting among boys (OR = 1.27, 95 % CI: 1.05-1.59), but not among girls. DiscussionIn this rural Guatemalan population, higher HAP exposure was associated with lower HAZ and WAZ. The associations between HAP and HAZ/stunting were stronger among boys. Reducing HAP might benefit childhood somatic growth in rural populations of low-income countries.

Association of household solid fuel use and long-term exposure to ambient air pollution with estimated 10-year high cardiovascular disease risk among postmenopausal women

This study aimed to explore the separate and joint effects of long-term ambient air pollution and household air pollution exposure on 10-year high cardiovascular disease (CVD) risk among postmenopausal women. A total of 4679 postmenopausal women from the China Health and Retirement Longitudinal Study (CHARLS) were included in this study. Information of fuel type was collected by standard questionnaires and use of solid fuel was considered as a proxy for household air pollution. Data of ambient air pollutants (PM1, PM2.5, PM10, SO2, NO2, CO, O3) were obtained from the ChinaHighAirPollutants (CHAP) datasets. Logistic regression models were performed to assess the separate and joint effects of long-term exposure to ambient air pollution and use of solid fuel on 10-year high CVD risk. We found use of solid fuel and its duration and ambient air pollutants (PM1, PM2.5, PM10, SO2, NO2) were all positively associated with 10-year high CVD risk among postmenopausal women (P < 0.05). Compared to those used clean fuel and exposed to low ambient air pollution levels, odds ratios (ORs) and 95% confidence intervals (CIs) for participants using solid fuels and exposed to high ambient air pollution levels (PM1, PM2.5, PM10, SO2, NO2, CO, O3) were 1.66 (1.35, 2.05), 1.66 (1.35, 2.04), 1.49 (1.22, 1.83), 1.28 (1.05, 1.57), 1.67 (1.34, 2.07), 1.28 (1.04, 1.57), 1.46 (1.18, 1.80), respectively. Moreover, significant additive interactions of solid fuel use with PM1 and PM2.5 on 10-year high CVD risk were observed, with approximately 18% and 23% of 10-year high risk of CVD attributable to the interaction. Overall, indoor and outdoor air pollution had separate and joint effects on 10-year high CVD risk among postmenopausal women. Therefore, simultaneously improving indoor and outdoor air quality are of great importance and could have a joint impact on prevention of CVD and improved health among postmenopausal women.