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.

Maternal prenatal exposure to household air pollution (HAP) is a critical public health concern with potential long-term implications for child respiratory health. The objective of this study is to assess the level of association between prenatal household air pollution and child respiratory health, and to identify which HAP pollutants are associated with specific respiratory illnesses or symptoms and to what degree. Relevant studies were retrieved from PubMed databases up to April 27, 2010, and their reference lists were reviewed. Random effects models were applied to estimate summarized relative risks (RRs) and 95% confidence intervals (CIs). The analysis involved 11 studies comprising 387 767 mother-child pairs in total, assessing various respiratory health outcomes in children exposed to maternal prenatal HAP. Children with prenatal exposure to HAP pollutants exhibited a summary RR of 1.26 (95% CI=1.08-1.33) with moderate between-study heterogeneity (I²=49.22%) for developing respiratory illnesses. Specific associations were found between prenatal exposure to carbon monoxide (CO) (RR=1.11, 95% CI: 1.09-1.13), Nitrogen Oxides (NOx) (RR=1.46, 95% CI: 1.09-1.60), and particulate matter (PM) (RR=1.26, 95% CI: 1.2186-1.3152) and child respiratory illnesses (all had I² close to 0%, indicating no heterogeneity). Positive associations with child respiratory illnesses were also found with ultrafine particles (UFP), polycyclic aromatic hydrocarbons (PAH), and ozone (O3). However, no significant association was observed for prenatal exposure to sulfur dioxide (SO2). In summary, maternal prenatal exposure to HAP may contribute to a higher risk of child respiratory health issues, emphasizing the need for interventions to reduce this exposure during pregnancy. Targeted public health strategies such as improved ventilation, cleaner cooking technologies, and awareness campaigns should be implemented to minimize adverse respiratory effects on children.

BACKGROUND: 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.
OBJECTIVE: 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.
METHODS: 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.
RESULTS: 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).
UNASSIGNED: 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.

Exposure to household air pollution (HAP) accounted for the loss of 86 million healthy lives in 2019, with almost half of all deaths due to lower respiratory infection among children under 5 years of age. Similarly, the situation in Punjab - Pakistan\'s largest province - is also not promising. This study was conducted to examine household energy consumption and respiratory symptoms among children under the age of five in rural and urban areas of Punjab. Using data from the Multiple Indicator Cluster Survey (MICS) 2017-18, logistic regression models were applied to the data of a sample of 35,000 children under the age of five living in households with polluting heating fuels. A hypothesis was formulated to investigate the relationship between polluting heating activities and respiratory infections among children under five. Those Children who live in households having traditional space heaters without chimneys are 50% more likely to have symptoms of Acute Respiratory Infection (ARI) compared to those whose households have chimneys with traditional space heaters. When households utilize polluting heating fuel, the likelihood of children experiencing rapid, shortness of breath increases by 49%, and the likelihood of children displaying ARI symptoms characterized by coughing rises by approximately 30%. This study proposed a complete banning of polluting heating activities and replacing it with cleaner ones using financial incentives. It is pertinent to raise awareness campaigns majorly focusing on the guidelines to adopt better heat output with less harmful emissions.

There is a growing evidence that the burning of unprocessed biomass fuels is associated with adverse health impacts. This study estimated the gaseous pollutants (CO, CO2, O3, SO2, and NO2) and particulate matters (PM2.5 and PM10) during the burning of biomass and liquefied petroleum gas (LPG) fuels and their impacts on the health of tribal women. The results revealed that the tribal women mainly used six types of unprocessed biomass fuels (dry leaves, cow dung cake, dry woods, twigs, rice straw, and agricultural residues) along with five types of traditional earthen stoves. The concentration of gaseous and PM was recorded as in the order of CO2 > SO2 > CO > O3 and total suspended particulate matter (TSPM) > PM10 > PM2.5, respectively. The pollutant concentration inside the kitchen room for biomass users was significantly (p < 0.001) higher than LPG users. The biomass using tribal women might be suffering from higher cardiovascular risk than LPG users. The lung function study results also indicated that the mean values of forced expiratory volume in 1 s (FEV1), forced vital capacity (FVC), and FEV1/FVC were lower among biomass users than LPG users. The correlation study shows that tribal women who were exposed to biomass smoke were in a more vulnerable position than those who used LPG. Moreover, the toxicological risk among tribal biomass users was observed high (3.52) compared to LPG users (0.39). On the other hand, the Monte Carlo probabilistic simulation model for uncertainty analysis revealed that the mean value of Hazard Quotient (HQ) for PM2.5 in kitchen room was observed as 4.31E-00 and 9.40E-01 for biomass and LPG users, respectively. Modelling study also revealed that exposure of duration and cooking time are extremely important for toxicological risk assessment. However, further long-term comprehensive studies are extremely important.

This study monitored the indoor air PAHs and PM2.5 exposure and their seasonal variations, so as to explore the potential health effects of household air pollution (HAP) on rural women\'s health in northwest China. It was detected that the average indoor PM2.5 and PAHs concentrations in the heating season were both significantly higher than those in the non-heating season (P<0.01). And they were positively correlated with the urinary 1-OHP levels respectively. Then the PAHs and 1-OHP were both significantly correlated with the urinary 8-OHdG levels (P<0.05). By statistical models, household PM2.5 and PAHs were closely related to urinary 1-OHP levels. Similarly, PM2.5, PAHs and 1-OHP all have significant effects with urinary 8-OHdG (P<0.05). Therefore, housewives in rural northwest China were exposed to higher HAP, and it could improve the risk for oxidative damage.