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

BACKGROUND: Cooking-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. METHODS: 557 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. RESULTS: 541 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. DISCUSSION: In 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.

Effects of a household air pollution intervention using liquefied petroleum gas stoves, continuous fuel distribution and behavioural messaging on dietary and sodium intake of adult women in Puno, Peru: a randomised controlled trial.

OBJECTIVE: Household air pollution (HAP) is a widespread environmental exposure worldwide. While several cleaner fuel interventions have been implemented to reduce personal exposures to HAP, it is unclear if cooking with cleaner fuels also affects the choice of meals and dietary intake. DESIGN: Individually randomised, open-label controlled trial of a HAP intervention. We aimed to determine the effect of a HAP intervention on dietary and Na intake. Intervention participants received a liquefied petroleum gas (LPG) stove, continuous fuel delivery and behavioural messaging during 1 year whereas control participants continued with usual cooking practices that involved the use of biomass-burning stoves. Dietary outcomes included energy, energy-adjusted macronutrients and Na intake at baseline, 6 months and 12 months post-randomisation using 24-h dietary recalls and 24-h urine. We used t-tests to estimate differences between arms in the post-randomisation period. SETTING: Rural settings in Puno, Peru. PARTICIPANTS: One hundred women aged 25-64 years. RESULTS: At baseline, control and intervention participants were similar in age (47·4 v. 49·5 years) and had similar daily energy (8894·3 kJ v. 8295·5 kJ), carbohydrate (370·8 g v. 373·3 g) and Na intake (4·9 g v. 4·8 g). One year after randomisation, we did not find differences in average energy intake (9292·4 kJ v. 8788·3 kJ; P = 0·22) or Na intake (4·5 g v. 4·6 g; P = 0·79) between control and intervention participants. CONCLUSIONS: Our HAP intervention consisting of an LPG stove, continuous fuel distribution and behavioural messaging did not affect dietary and Na intake in rural Peru.

Biomass Smoke Exposure and Atopy among Young Children in the Western Highlands of Guatemala: A Prospective Cohort Study.

Women and children in rural regions of low-income countries are exposed to high levels of household air pollution (HAP) as they traditionally tend to household chores such as cooking with biomass fuels. Early life exposure to air pollution is associated with aeroallergen sensitization and developing allergic diseases at older ages. This prospective cohort study assigned HAP-reducing chimney stoves to 557 households in rural Guatemala at different ages of the study children. The children's air pollution exposure was measured using personal CO diffusion tubes. Allergic outcomes at 4-5 years old were assessed using skin prick tests and International Study of Asthma and Allergies in Childhood (ISAAC)-based questionnaires. Children assigned to improved stoves before 6 months old had the lowest HAP exposure compared to the other groups. Longer exposure to the unimproved stoves was associated with higher risks of maternal-reported allergic asthma (OR = 2.42, 95% CI: 1.11-5.48) and rhinitis symptoms (OR = 2.01, 95% CI: 1.13-3.58). No significant association was found for sensitization to common allergens such as dust mites and cockroaches based on skin prick tests. Reducing HAP by improving biomass burning conditions might be beneficial in preventing allergic diseases among children in rural low-income populations.

Effectiveness of a home-environmental intervention package and an early child development intervention on child health and development in high-altitude rural communities in the Peruvian Andes: a cluster-randomised controlled trial.

BACKGROUND: Unsafe drinking water, poor sanitation and hygiene, exposure to household air pollution and low cognitive and socio-emotional stimulation are risk factors affecting children in low- and middle-income countries. We implemented an integrated home-environmental intervention package (IHIP), comprising a kitchen sink, hygiene education and a certified improved biomass cookstove, and an early child development (ECD) programme to improve children´s health and developmental outcomes in the rural high-altitude Andes of Peru. METHODS: We conducted a one-year cluster-randomised controlled trial among 317 children < 36 months divided into 4 arms (IHIP + ECD, IHIP, ECD, and Control) and 40 clusters (10 clusters per arm). ECD status (socio-emotional, fine and gross motor, communication, cognitive skills, and an overall performance) measured with the Peruvian Infant Development Scale and the occurrence of self-reported child diarrhoea from caretakers were primary outcomes. Secondary outcomes included the occurrence of acute respiratory infections and the presence of thermo-tolerant faecal bacteria in drinking water. The trial was powered to compare each intervention against its control arm but it did not allow pairwise comparisons among the four arms. Primary analysis followed the intention-to-treat principle. For the statistical analysis, we employed generalised estimating equation models with robust standard errors and an independent correlation structure. RESULTS: We obtained ECD information from 101 children who received the ECD intervention (individually and combined with IHIP) and 102 controls. Children who received the ECD intervention performed better in all the domains compared to controls. We found differences in the overall performance (64 vs. 39%, odd ratio (OR): 2.8; 95% confidence interval (CI): 1.6-4.9) and the cognitive domain (62 vs 46%, OR: 1.9; 95% CI: 1.1-3.5). Data analysis of child morbidity included 154 children who received the IHIP intervention (individually and combined with ECD) and 156 controls. We recorded 110,666 child-days of information on diarrhoea morbidity and observed 1.3 mean episodes per child-year in the children who received the IHIP intervention and 1.1 episodes in the controls. This corresponded to an incidence risk ratio of 1.2 (95% CI: 0.8-1.7). CONCLUSIONS: Child stimulation improved developmental status in children, but there was no health benefit associated with the home-environmental intervention. Limited year-round access to running water at home and the possible contamination of drinking water after boiling were two potential factors linked to the lack of effect of the home-environmental intervention. Potential interactions between ECD and home-environmental interventions need to be further investigated. TRIAL REGISTRATION: ISRCTN, ISRCTN-26548981. Registered 15 January 2018-Retrospectively registered, https://doi.org/10.1186/ISRCTN26548981 .

Household air pollution from wood-burning cookstoves and C-reactive protein among women in rural Honduras.

Household air pollution from solid fuel combustion was estimated to cause 2.31 million deaths worldwide in 2019; cardiovascular disease is a substantial contributor to the global burden. We evaluated the cross-sectional association between household air pollution (24-h gravimetric kitchen and personal particulate matter (PM2.5) and black carbon (BC)) and C-reactive protein (CRP) measured in dried blood spots among 107 women in rural Honduras using wood-burning traditional or Justa (an engineered combustion chamber) stoves. A suite of 6 additional markers of systemic injury and inflammation were considered in secondary analyses. We adjusted for potential confounders and assessed effect modification of several cardiovascular-disease risk factors. The median (25th, 75th percentiles) 24-h-average personal PM2.5 concentration was 115 µg/m3 (65,154 µg/m3) for traditional stove users and 52 µg/m3 (39, 81 µg/m3) for Justa stove users; kitchen PM2.5 and BC had similar patterns. Higher concentrations of PM2.5 and BC were associated with higher levels of CRP (e.g., a 25% increase in personal PM2.5 was associated with a 10.5% increase in CRP [95% CI: 1.2-20.6]). In secondary analyses, results were generally consistent with a null association. Evidence for effect modification between pollutant measures and four different cardiovascular risk factors (e.g., high blood pressure) was inconsistent. These results support the growing evidence linking household air pollution and cardiovascular disease.

Poluição do Ar: uma revisão de escopo para recomendações clínicas para a medicina de família e comunidade / Air pollution: a scoping review of clinical recommendations for family and community medicine / Contaminación del Aire: una revisión de objetivo para recomendaciones clínicas para la medicina familiar y comunitaria

Introdução: As mortes atribuíveis à poluição do ar em longo prazo chegam a 9 milhões ao ano, concentrando-se principalmente em países de baixa e média renda como o Brasil. Classifica-se a poluição do ar em: domiciliar (indoor) ou ambiente (outdoor). A inalação de poluentes está relacionada com o aumento da incidência e desenvolvimento de condições clínicas, como doenças cardiovasculares, respiratórias e outras, que fazem parte da prática da medicina de família e comunidade. Objetivo: Verificar as evidências clínicas para a abordagem da poluição do ar relacionada à saúde humana no contexto da prática na Atenção Primária à Saúde. Métodos: Revisão de escopo do papel clínico da medicina de família e comunidade em relação à poluição do ar e saúde, voltada para questões clínicas associadas com a poluição do ar. Incluíram-se 35 artigos nesta revisão. Recomendações clínicas: Em nível individual, destacam-se a redução do uso de fogões a lenha, o uso de estratégias de proteção de fontes poluidoras (como queimadas, vias de trânsito e indústria), a filtragem do ar, o estímulo ao transporte ativo, a cessação do tabagismo. Essas recomendações devem ser complementares às políticas governamentais relacionadas à poluição do ar. Propõem-se perguntas para a entrevista clínica. Exploram-se recomendações específicas sobre uso de máscaras, atividade física e COVID-19. Sugerem-se temas de pesquisa que podem ser realizadas na Atenção Primária à Saúde e o papel da medicina de família e comunidade nesse contexto. Considerações: A inclusão na classificação internacional de atenção primária e no Código internacional de Doenças poderia melhorar a notificação e os estudos epidemiológicos sobre o assunto.

Introduction: Deaths attributable to long-term air pollution are estimated to be as high as 9 million a year, mainly concentrated in low- and middle-income countries such as Brazil. Air pollution is classified as household (indoor) or ambient(outdoor). Inhalation of pollutants is related to the increased incidence and development of clinical conditions, such as cardiovascular, respiratory and other diseases, which are part of the practice of family doctors. Objective: To reviewthe clinical evidence for an approach to air pollution related to human health in the context of the practice in primary health care. Methods: A scoping review was carried out with a cross-sectional focus on the role of primary health care in relation to air pollution and health, focusing on clinical issues related to air pollution. Results: A total of 35 articles were included in this review. Clinical recommendations at the individual level were: reduction in the use of solid fuels in wood stoves, use of strategies to protect polluting sources (such as forest fires, roads and industry), air filtration, promotion of active transport and smoking cessation. These actions must be complementary to government policies related to air pollution reduction. Clinical interview questions were proposed. Specific recommendations on the use of masks, physical activity and COVID-19 were explored. Research topics were proposed that could be carried out in primary health care and the role of family doctors in this context. Considerations: The inclusion of "exposure to air pollution" in the International Classification of Primary Care and in the International Classification of Diseases could improve notification and epidemiological studies on the subject.

Introducción: Las muertes atribuibles a la contaminación del aire a largo plazo alcanzan los 9 millones por año, concentradas principalmente en países de ingresos bajos y medios como Brasil. La contaminación del aire se clasifica en: doméstica (indoor) o ambiental (outdoor). La inhalación de contaminantes está relacionada con el aumento de la incidencia y el desarrollo de condiciones clínicas, como enfermedades cardiovasculares, respiratorias y otras; que forman parte de la práctica de la medicina familiar y comunitaria (MFC). Objetivo: verificar la evidencia clínica para el abordaje de la contaminación atmosférica relacionada con la salud humana en el contexto de la práctica en Atención Primaria de Salud (APS). Métodos: Se realizó una revisión de objetivo con un enfoque transversal sobre el papel de la APS con relación a la contaminación atmosférica y la salud, con foco en los aspectos clínicos relacionados con la contaminación atmosférica. En esta revisión se incluyeron 35 artículos. Recomendaciones clínicas: A nivel individual, hay reducción en el uso de estufas de leña, uso de estrategias de protección de fuentes contaminantes (como incendios, carreteras e industria), filtración de aire, estimulación del transporte activo, abandono del tabaquismo. Estos deben ser complementarios a las políticas gubernamentales relacionadas con la contaminación del aire. Se proponen preguntas de entrevista clínica. Se exploran recomendaciones específicas sobre el uso de máscaras, actividad física y COVID-19. Se proponen temas de investigación que pueden llevarse a cabo en la APS y el papel del MFC en este contexto. Consideraciones: la inclusión en la Clasificación Internacional de Atención Primaria (CIAP) y en el Código Internacional de Enfermedades (CIE) podría mejorar la notificación y los estudios epidemiológicos sobre el tema.

Reduced Black Carbon Concentrations following a Three-Year Stepped-Wedge Randomized Trial of the Wood-Burning Justa Cookstove in Rural Honduras.

Introduction: Household air pollution from cooking-related biomass combustion remains a leading risk factor for global health. Black carbon (BC) is an important component of particulate matter (PM) in household air pollution. We evaluated the impact of the engineered, wood-burning Justa stove intervention on BC concentrations. Methods: We conducted a 3-year stepped-wedge randomized controlled trial with 6 repeated visits among 230 female primary cooks in rural Honduras. Participants used traditional stoves at baseline and were randomized to receive the Justa after visit 2 or after visit 4. At each visit, we measured 24-hour gravimetric personal and kitchen fine PM (PM2.5) concentrations and estimated BC mass concentrations (Sootscan Transmissometer). We conducted intent-to-treat analyses using linear mixed models with natural log-transformed 24-hour personal and kitchen BC. Results: BC concentrations were reduced for households assigned to the Justa vs. traditional stoves: e.g., personal BC geometric mean (GSD), 3.6 µg/m3 (6.4) vs. 11.5 µg/m3 (4.6), respectively. Following the intervention, we observed 53% (95% CI: 35-65%) lower geometric mean personal BC concentrations and 76% (95% CI: 66-83%) lower geometric mean kitchen BC concentrations. Conclusions: The Justa stove intervention substantially reduced BC concentrations, mitigating household air pollution and potentially benefitting human and climate health.

Map of Evidence: interventions to reduce exposure to household air pollution

This evidence map was developed to identify, summarize, and communicate to key stakeholders the findings of evidence on interventions to reduce exposure to household air pollution (HAP). The map synthesizes evidence from 48 literature reviews published on technological and sociocultural interventions and others (potentialities of public policies like incentives) to address health, environmental and economic impacts associated to HAP. Furthermore, this map seeks to inform decision-making processes on strategic interventions and most effective policies. Main results: Most of the existing HAP interventions to address indoor air quality have been focused on evaluating improved stove interventions that still use solid fuels (n = 39). It has been identified that Interventions with clean fuels (LPG, electricity, and others) are the most effective in impacting the health outcomes and reducing household air pollutants. Only six reviews analyzed or reported outcomes of sociocultural interventions (health education) aimed at reducing air pollution in homes; some showed positive impacts on health. Three reviews reported the effects of changes in people's behaviors when cooking food, which have improved indoor air quality. All authors agree on the importance of changing behavior and community practices as an essential element for the sustainability of improved kitchen interventions. Four reviews evaluated at the synergy between policies to reduce household air pollution and outdoor pollution, as well as other environmental health concerns. These reviews allow the conclusion that synergies between policies are much more effective at reducing air pollution and its impacts on the health of communities.

Exposure to indoor air pollution/outdoor air pollution: the silent killers ­ A pilot study / Exposição à poluição do ar interno/poluição do ar externo: os assassinos silenciosos ­ Estudo piloto

Objective: To identify possible risks factors of exposure to indoor air pollution (IAP)/outdoor air pollution (OAP) and their relationship with noncommunicable diseases in men and women treated by primary care physicians. Method: In total, 551 patients (382 women) attended three basic health units in Uruguaiana, Brazil, for various complaints, and completed a questionnaire about risk factors for exposure to IAP/OAP. Results: Women were significantly more exposed to wood-burning pollutants (79.6% vs. 52.7%, p < 0.0001) for having more housework-related activities; men had more outdoor activities and spent extended periods in traffic (47.3% vs. 18.8%, p < 0.0001). Arterial hypertension (AH)/ chronic respiratory disease (CRD) were more frequent among women. Patients with AH/CRD were more exposed to OAP because of their work (18.1% vs. 11%, p = 0.02) or for living near a source of air pollution (45.6% vs. 29.6%, p = 0.0002) or on a street with heavy traffic (41.7% vs. 33%, p = 0.04). Passive smoking, active smoking, using wood, charcoal, or firewood for cooking, heating, or drying, or burning charcoal indoors were not associated with a higher prevalence of AH/CRD. Conclusion: Exposure to OAP was associated with AH/CRD. Women were more exposed to IAP from burning firewood, and men were more exposed to fossil fuel burning. Knowledge of these behaviors should be directed to primary care physicians and all health professionals so that preventive and educational measures can be implemented.

Objetivo: Identificar possíveis fatores de risco da exposição à poluição intradomiciliar (PID) e extradomiciliar (PED) e sua relação com doenças não transmissíveis (DNT) em homens e mulheres tratados por médicos de atenção primária. Método: Quinhentos e cinquenta e um pacientes (382 mulheres) atendidos em três unidades básicas de saúde em Uruguaiana, Brasil, por queixas diversas, responderam a um questionário sobre os fatores de risco para exposição à PID/PED. Resultados: As mulheres foram significantemente mais expostas aos poluentes da queima de lenha (79,6% vs. 52,7%, p < 0,0001) por terem mais atividades domésticas; os homens praticaram mais atividades ao ar livre e passaram longos períodos no trânsito (47,3% vs. 18,8%, p < 0,0001). Hipertensão arterial (HA) / Doença respiratória crônica (DRC) foram mais frequentes entre as mulheres. Pacientes com HA/DRC foram mais expostos à PED devido ao trabalho (18,1% vs. 11%, p = 0,02), ou por viver perto de uma fonte de poluição do ar (45,6% vs. 29,6%, p = 0,0002), ou em uma rua com trânsito intenso (41,7% vs. 33%, p = 0,04). O fumo passivo, o fumo ativo, o uso de lenha ou carvão para cozinhar, aquecer ou secar ou queimar carvão em ambientes fechados não foram associados a maior prevalência de HA/DRC. Conclusão: A exposição à PED foi associada a HA/CRD. As mulheres foram mais expostas à PID pela queima de lenha, e os homens foram mais expostos à queima de combustíveis fósseis. O conhecimento destes comportamentos deve ser direcionado aos médicos da atenção básica e a todos os profissionais da saúde, para que medidas preventivas e educacionais possam ser implementadas.

Household use of polluting cooking fuels and late-life cognitive function: A harmonized analysis of India, Mexico, and China.

INTRODUCTION: Exposure to high levels of air pollution is associated with poor health, including worse cognitive function. Whereas many studies of cognition have assessed outdoor air pollution, we evaluate how exposure to air pollution from combustion of polluting household fuels relates with cognitive function using harmonized data from India, Mexico, and China. MATERIALS & METHODS: We analyze adults age 50+ in three nationally representative studies of aging with common data collection methods: the 2017-2019 Longitudinal Aging Study in India (n = 50,532), 2015 Mexican Health and Aging Study (n = 12,883), and 2013 China Health and Retirement Longitudinal Study (n = 12,913). Use of polluting fuels was assessed by self-report of wood, coal, kerosene, crop residue, or dung for cooking. Cognitive function was measured by performance across several cognitive domains and summarized into a total cognition score. We used linear regression, by country, to test how polluting cooking fuel use relates with cognition adjusting for key demographic and socioeconomic factors. RESULTS: Approximately 47%, 12%, and 48% of respondents in India, Mexico, and China, respectively, relied primarily on polluting cooking fuel, which was more common in rural areas. Using polluting cooking fuels was consistently associated with poorer cognitive function in all countries, independent of demographic and socioeconomic characteristics. Adjusted differences in cognitive function between individuals using polluting and clean cooking fuel were equivalent to differences observed between individuals who were 3 years of age apart in Mexico and China and 6 years of age apart in India. Across countries, associations between polluting cooking fuel use and poorer cognition were larger for women. CONCLUSIONS: Results suggest that household air pollution from the use of polluting cooking fuel may play an important role in shaping cognitive outcomes of older adults in countries where reliance on polluting fuels for domestic energy needs still prevails. As these countries continue to age, public health efforts should seek to reduce reliance on these fuels.

Household air pollution and blood markers of inflammation: A cross-sectional analysis.

Household air pollution (HAP) from biomass stoves is a leading risk factor for cardiopulmonary outcomes; however, its toxicity pathways and relationship with inflammation markers are poorly understood. Among 180 adult women in rural Peru, we examined the cross-sectional exposure-response relationship between biomass HAP and markers of inflammation in blood using baseline measurements from a randomized trial. We measured markers of inflammation (CRP, IL-6, IL-10, IL-1ß, and TNF-α) with dried blood spots, 48-h kitchen area concentrations and personal exposures to fine particulate matter (PM2.5 ), black carbon (BC), and carbon monoxide (CO), and 48-h kitchen concentrations of nitrogen dioxide (NO2 ) in a subset of 97 participants. We conducted an exposure-response analysis between quintiles of HAP levels and markers of inflammation. Markers of inflammation were more strongly associated with kitchen area concentrations of BC than PM2.5 . As expected, kitchen area BC concentrations were positively associated with TNF-α (pro-inflammatory) concentrations and negatively associated with IL-10, an anti-inflammatory marker, controlling for confounders in single- and multi-pollutant models. However, contrary to expectations, kitchen area BC and NO2 concentrations were negatively associated with IL-1ß, a pro-inflammatory marker. No associations were identified for IL-6 or CRP, or for any marker in relation to personal exposures.

Impact of the wood-burning Justa cookstove on fine particulate matter exposure: A stepped-wedge randomized trial in rural Honduras.

TRIAL DESIGN: We evaluated the impact of a biomass stove intervention on fine particulate matter (PM2.5) concentrations using an individual-level, stepped-wedge randomized trial. METHODS: We enrolled 230 women in rural Honduran households using traditional biomass stoves and randomly allocated them to one of two study arms. The Justa stove, the study intervention, was locally-sourced, wood-burning, and included an engineered combustion chamber and chimney. At each of 6 visits over 3 years, we measured 24-hour gravimetric personal and kitchen PM2.5 concentrations. Half of the households received the intervention after Visit 2 and half after Visit 4. We conducted intent-to-treat analyses to evaluate the intervention effect using linear mixed models with log-transformed kitchen or personal PM2.5 (separately) as the dependent variable, adjusting for time. We also compared PM2.5 concentrations to World Health Organization (WHO) guidelines. RESULTS: Arms 1 and 2 each had 115 participants with 664 and 632 completed visits, respectively. Median 24-hour average personal PM2.5 exposures were 81 µg/m3 (25th-75th percentile: 50-141 µg/m3) for the traditional stove condition (n=622) and 43 µg/m3 (25th-75th percentile: 27-73 µg/m3) for the Justa stove condition (n=585). Median 24-hour average kitchen concentrations were 178 µg/m3 (25th-75th percentile: 69-440 µg/m3; n=629) and 53 µg/m3 (25th-75th percentile: 29-103 µg/m3; n=578) for the traditional and Justa stove conditions, respectively. The Justa intervention resulted in a 32% reduction in geometric mean personal PM2.5 (95% confidence interval [CI]: 20-43%) and a 56% reduction (95% CI: 46-65%) in geometric mean kitchen PM2.5. During rainy and dry seasons, 53% and 41% of participants with the Justa intervention had 24-hour average personal PM2.5 exposures below the WHO interim target-3 guideline (37.5 µg/m3), respectively. CONCLUSION: The Justa stove intervention substantially lowered personal and kitchen PM2.5 and may be a provisional solution that is feasible for Latin American communities where cleaner fuels may not be available, affordable, or acceptable for some time. Clinicaltrials.gov: NCT02658383.

Exposure levels to PM2.5 and black carbon for people with disabilities in rural homes of Colombia.

Indoor exposure to air pollutants emitted by solid fuels used for cooking or heating homes remains as a problem to solve. The most affected people are newborns, mothers, children, and people with disabilities, due to the time they spend at home. This study is the first in a rural area of South America, which measures indoor air pollutants (PM2.5 and black carbon) in different environments, inhabited by people with disabilities. The research was supported through a sociodemographic characterization, a methodology useful for future studies, continuous monitoring for 72 h of pollutants, and emission sources, cooking habits, and pre-existing diseases were identified. The primary sources of emissions are improved wood-burning stoves and their chimney. In households where firewood is used, the average concentrations of PM2.5 were the highest (between 10.9 and 3302.5 µg/m3), as were the average concentrations of BC (average 72 h between 2.6 and 51.2 µg/m3) compared with the houses that use gas (average 72 h between 2.6 and 6 µg/m3). In 57% of the households visited, the World Health Organization (WHO) guidelines for PM2.5 (25 µg/m3 for 24 h) were exceeded. The results reveal that rural concentrations of BC can be up to 2.5 times higher than those of an urban area with high vehicular traffic and high population density and could be used to establish a baseline that allows the implementation of control mechanisms to reduce pollution of indoor air.

Effects of a Household Air Pollution Intervention with Liquefied Petroleum Gas on Cardiopulmonary Outcomes in Peru. A Randomized Controlled Trial.

Rationale: Approximately 40% of people worldwide are exposed to household air pollution (HAP) from the burning of biomass fuels. Previous efforts to document health benefits of HAP mitigation have been stymied by an inability to lower emissions to target levels. Objectives: We sought to determine if a household air pollution intervention with liquefied petroleum gas (LPG) improved cardiopulmonary health outcomes in adult women living in a resource-poor setting in Peru. Methods: We conducted a randomized controlled field trial in 180 women aged 25-64 years living in rural Puno, Peru. Intervention women received an LPG stove, continuous fuel delivery for 1 year, education, and behavioral messaging, whereas control women were asked to continue their usual cooking practices. We assessed for stove use adherence using temperature loggers installed in both LPG and biomass stoves of intervention households. Measurements and Main Results: We measured blood pressure, peak expiratory flow (PEF), and respiratory symptoms using the St. George's Respiratory Questionnaire at baseline and at 3-4 visits after randomization. Intervention women used their LPG stove exclusively for 98% of days. We did not find differences in average postrandomization systolic blood pressure (intervention - control 0.7 mm Hg; 95% confidence interval, -2.1 to 3.4), diastolic blood pressure (0.3 mm Hg; -1.5 to 2.0), prebronchodilator peak expiratory flow/height2 (0.14 L/s/m2; -0.02 to 0.29), postbronchodilator peak expiratory flow/height2 (0.11 L/s/m2; -0.05 to 0.27), or St. George's Respiratory Questionnaire total score (-1.4; -3.9 to 1.2) over 1 year in intention-to-treat analysis. There were no reported harms related to the intervention. Conclusions: We did not find evidence of a difference in blood pressure, lung function, or respiratory symptoms during the year-long intervention with LPG. Clinical trial registered with www.clinicaltrials.gov (NCT02994680).

Contaminación del aire y su influencia en la incidencia de enfermedades respiratorias en Santa Elena Ecuador 2020 / Air pollution and its influence on the incidence of respiratory diseases in Santa Elena Ecuador 2020

El uso de combustibles sólidos para cocinar representa el principal riesgo ambiental en América, afectando a 90 millones de personas y causando el fallecimiento de 83.000 personas en el continente en 2016, mientras que en el mundo esta última cifra alcanza más de 4 millones de personas. Al quemar combustibles sólidos como madera, carbón en fogones o estufas se emite monóxido de carbono y elevados niveles de material particulado que quedan suspendidas en el aire. Por su parte, el monóxido de carbono es un reconocido contaminante atmosférico, con gran capacidad para afectar el organismo humano, con propiedades inoloras, incoloras y no irritantes que dificultan su detección. El grado de exposición al monóxido de carbono es evaluado mediante la medición de la saturación de Carboxihemoglobina en sangre, que se determina con técnicas como espectrofotometría de absorción en disolución. Esta investigación se realizó en la comuna de Ayangue, Ecuador, en comedores que continúan la tradición de cocinar en leña como atrayente para los turistas. Se halló una correlación positiva moderada entre el valor promedio de COHb con las horas de la jornada diaria de trabajo (r = 0,674); con el uso de leña o carbón para cocinar en el trabajo (r = 0,537; 88%); y con la presencia de síntomas físicos como el dolor de cabeza (r = 0,616) y náuseas (r = 0,524). Estas alteraciones fisiológicas se presentan durante o inmediatamente después de la jornada de trabajo, según el 88% de los sintomáticos(AU)

The use of solid fuels for cooking represents the main environmental risk in America, affecting 90 million people and causing the death of 83,000 people on the continent in 2016, while in the world this last figure reaches more than 4 million people. Burning solid fuels such as wood, charcoal in stoves or stoves emits carbon monoxide and high levels of particulate matter that are suspended in the air. For its part, carbon monoxide is a recognized atmospheric pollutant, with a great capacity to affect the human organism, with odorless, colorless and non-irritating properties that make it difficult to detect. The degree of exposure to carbon monoxide is evaluated by measuring the saturation of carboxyhemoglobin in blood, which is determined with techniques such as absorption spectrophotometry in solution. This research was carried out in the Ayangue commune, Ecuador, in dining rooms that continue the tradition of cooking on firewood as an attraction for tourists. A moderate positive correlation was found between the average COHb value and the hours of the daily working day (r = 0.674); with the use of firewood or charcoal for cooking at work (r = 0.537; 88%); and with the presence of physical symptoms such as headache (r = 0.616) and nausea (r = 0.524). These physiological alterations appear during or immediately after the work day, according to 88% of the symptomatic ones(AU)

Association between coal and firewood combustion and hospital admissions and mortality in Chile 2015 - An ecological approach.

INTRODUCTION AND OBJECTIVE: Burning coal and firewood generates toxic emissions that are associated with respiratory illness, cardiovascular disease, and even death. The aim of the study is to evaluate the association between county-level prevalence of household coal and firewood use and health outcomes, including total, respiratory, and cardiovascular mortality, as well as total and respiratory hospitalization rates. MATERIAL AND METHODS: The ecological study included data on the use of household coal and firewood in 139 counties obtained from the 2015 Chilean National Socio-economic Characterization Survey. Total, respiratory, and cardiovascular mortality, as well as total and respiratory hospitalization rates, were obtained from the Department of Health Statistics. Poisson models with robust error variance, Pearson linear correlation coefficients, and scatterplots were used to explore associations between household coal and firewood use and morbidity-mortality, stratifying by geographic zone. RESULTS: Total, respiratory, and cardiovascular mortality and total and respiratory hospitalization rates were 5.7 per 1,000, 552 per 100,000, 157 per 100,000, 92.5 per 1000, and 8.8 per 1000 inhabitants, respectively. The median prevalence of coal use for residential cooking, heating, or water heating was 3.64%, while the median prevalence of firewood combustion was 12%. In southern counties, age- and gender-adjusted respiratory mortality increased 2.02 (95% CI: 1.17-3.50), 1.5 (95% CI: 1.11-1.89), and 1.76-fold (95% CI: 1.19-2.60) for each percentage increase in household coal and firewood use for heating, cooking and heating water, respectively. CONCLUSIONS: The prevalence of household coal and firewood used for heating and cooking was positively correlated with respiratory mortality and hospitalization in southern zone counties.

Household air pollution exposure and associations with household characteristics among biomass cookstove users in Puno, Peru.

BACKGROUND: Household air pollution (HAP) from combustion of biomass fuel, such as wood and animal dung, is among the leading environmental risk factors for preventable disease. Close to half of the world's population relies on biomass cookstoves for their daily cooking needs. Understanding factors that affect HAP can inform measures to maximize the effectiveness of cookstove interventions in a cost-effective manner. However, the impact of kitchen and household characteristics, as well as the presence of secondary stoves, on HAP concentrations is poorly understood in Puno, Peru. OBJECTIVE: To explore how household characteristics explain variability of kitchen area concentrations and personal exposures to CO, PM2.5 and BC from biomass cookstoves among women in rural Peru. METHODS: Household characteristics (including kitchen materials and layout, wealth, and cooking behaviors) and HAP measurements were collected from 180 households in Puno, Peru, from baseline measurements of a randomized trial. Kitchen area concentrations and personal exposures to carbon monoxide (CO), fine particulate matter (PM2.5) and black carbon (BC) were sampled for 48 h. We implemented simple and multivariable linear regression models to determine the associations between household characteristics and both kitchen area concentration and personal exposure to each pollutant. RESULTS: Mean daily kitchen area concentrations and personal exposures to HAP were, on average, 48 times above World Health Organization indoor guidelines for PM2.5. We found that roof type explained the most variability in HAP and was strongly associated with both kitchen area concentrations and personal exposures for all pollutants after adjusting for other household variables. Personal exposures were 27%-36% lower for PM2.5, CO and BC, in households with corrugated metal roofs, compared to roofs made of natural materials (straw, totora or reed) after adjusting for other factors. Higher kitchen area concentrations were also associated with less wealth, owning more animals, or sampling during the dry season in multivariable models. Having a liquefied petroleum gas (LPG) stove and having a chimney were associated with lower personal exposures, but were not associated with kitchen area concentrations. Personal exposures were lower by 21% for PM2.5 and 28% for CO and BC concentrations among participants who had both LPG and biomass stoves compared to those with only biomass cookstoves adjusting for other household factors. CONCLUSIONS: Characterizing HAP within different settings can help identify effective and culturally-relevant solutions to reduce HAP exposures. We found that housing roof type is strongly related to kitchen area concentrations and personal exposures to HAP, perhaps because of greater ventilation in kitchens with metal roofs compared to those with thatch roofs. Although HAP concentrations remained above guidelines for all households, promoting use of metal roof materials and LPG stoves may be actionable interventions that can help reduce exposures to HAP in high-altitude rural Peru and similar settings.

Adoption and impact of improved cookstoves in Lambayeque, Peru, 2017.

INTRODUCTION: Approximately three billion people in Asia, Africa, and the Americas cook with biomass, cleaner cooking technologies with the potential to reduce household air pollution exposure. It is necessary to assess the adoption and long-term use of these stoves, measure perceived benefits among users, and use this information to provide feedback to programs that are implementing new cooking technologies. The aim of this study is to determine the level of adoption and impact of improved biomass cookstoves in the rural area of Lambayeque, Peru, in 2017. METHODS: A descriptive cross-sectional study was conducted. A total of 52 homes were surveyed in the districts of Pacora and Íllimo where improved biomass stoves were introduced between 2005 and 2013. A questionnaire for the assessment of adoption and impact indexes proposed by the Global Alliance for Clean Cookstoves was applied. The STROBE checklist was used. RESULTS: The mean number of years with the improved biomass cookstove was 9.1 (standard deviation: 2.9); 51.9% always used the improved stove, and 34.6% never used it due to destruction during the El Niño phenomenon in 2017. The median impact index was 5.62; 19.2% had a very good/good adoption. The median adoption index was 6.5; 25% had a very high/high impact. The use of the traditional or open fire biomass stove persisted in 61.5% of the houses. CONCLUSION: The adoption and impact of improved biomass cookstoves were acceptable, but traditional stove use persisted in more than half of the houses. Households used a mix of different stove technologies. Gas stoves were used more frequently for breakfast or dinner, while the traditional biomass stoves were used for larger lunchtime meals.

Inverse association between dengue, chikungunya, and Zika virus infection and indicators of household air pollution in Santa Rosa, Guatemala: A case-control study, 2011-2018.

BACKGROUND: Dengue, chikungunya, and Zika viruses are increasingly important public health problems. Burning vegetation, leaves, and other plant products have been shown to be effective mosquito repellents for their vector, Aedes spp., but there has been scant research on whether firewood cooking smoke in households influences mosquito populations or mosquito-borne diseases. About 2.9 billion people worldwide use biomass fuel for household cooking and heating, resulting in an estimated 1.6 million deaths annually from household air pollution (HAP)-related diseases. Global health agencies now encourage households to transition from biomass to clean fuels, but it is unclear whether such interventions may actually increase risk for mosquito-borne diseases. This retrospective case-control study evaluated associations between arboviral infections and cooking with firewood in Santa Rosa, Guatemala. METHOD: Vigilancia Integrada Comunitaria (VICo) was a prospective public health surveillance system for bacterial, parasitic, and viral causes of diarrheal, neurological, respiratory, and febrile illnesses in hospitals and clinics in the department of Santa Rosa, Guatemala. Enrolled VICo in-patients and out-patients during 2011-2018 were interviewed using standardized questionnaires on demographics and household characteristics. Blood and stool specimens were collected and tested to identify the etiologies presenting symptoms. Cases were defined as laboratory-positive for dengue, chikungunya, or Zika virus infections. Controls were laboratory-positive for bacterial and viral diarrheal illnesses (e.g., Salmonella, Shigella, Campylobacter, Escherichia coli, rotavirus, norovirus, sapovirus, or astrovirus). Cooking with firewood, kitchen location, stove type, and firewood cooking frequency were the independent exposure variables. Logistic regression models were used to analyze unadjusted and adjusted associations between arboviral infections and exposures of interest. RESULT: There were 311 arboviral cases and 1,239 diarrheal controls. Arboviral infections were inversely associated with cooking with firewood in the main house (AOR: 0.22; 95% CI: 0.08-0.57), cooking with firewood on an open hearth (AOR: 0.50; 95% CI: 0.33-0.78), and cooking with firewood ≥5 times per week (AOR: 0.54; 95% CI: 0.36-0.81), adjusting for age, sex, ethnicity, socioeconomic status index, number of people per household, community population density, community elevation, recruitment location, season, and admission year. CONCLUSION: Several primary determinants of HAP exposure were inversely associated with arboviral infections. Additional studies are needed to understand whether interventions to reduce HAP might actually increase risk for mosquito-borne infectious diseases, which would warrant improved education and mosquito control efforts in conjunction with fuel interventions.

Indoor air pollution concentrations and cardiometabolic health across four diverse settings in Peru: a cross-sectional study.

BACKGROUND: Indoor air pollution is an important risk factor for health in low- and middle-income countries. METHODS: We measured indoor fine particulate matter (PM2.5) and carbon monoxide (CO) concentrations in 617 houses across four settings with varying urbanisation, altitude, and biomass cookstove use in Peru, between 2010 and 2016. We assessed the associations between indoor pollutant concentrations and blood pressure (BP), exhaled carbon monoxide (eCO), C-reactive protein (CRP), and haemoglobin A1c (HbA1c) using multivariable linear regression among all participants and stratifying by use of biomass cookstoves. RESULTS: We found high concentrations of indoor PM2.5 across all four settings (geometric mean ± geometric standard deviation of PM2.5 daily average in µg/m3): Lima 41.1 ± 1.3, Tumbes 35.8 ± 1.4, urban Puno 14.1 ± 1.7, and rural Puno 58.8 ± 3.1. High indoor CO concentrations were common in rural households (geometric mean ± geometric standard deviation of CO daily average in ppm): rural Puno 4.9 ± 4.3. Higher indoor PM2.5 was associated with having a higher systolic BP (1.51 mmHg per interquartile range (IQR) increase, 95% CI 0.16 to 2.86), a higher diastolic BP (1.39 mmHg higher DBP per IQR increase, 95% CI 0.52 to 2.25), and a higher eCO (2.05 ppm higher per IQR increase, 95% CI 0.52 to 3.57). When stratifying by biomass cookstove use, our results were consistent with effect measure modification in the association between PM2.5 and eCO: among biomass users eCO was 0.20 ppm higher per IQR increase in PM2.5 (95% CI - 2.05 to 2.46), and among non-biomass users eCO was 5.00 ppm higher per IQR increase in PM2.5 (95% CI 1.58 to 8.41). We did not find associations between indoor air concentrations and CRP or HbA1c outcomes. CONCLUSIONS: Excessive indoor concentrations of PM2.5 are widespread in homes across varying levels of urbanisation, altitude, and biomass cookstove use in Peru and are associated with worse BP and higher eCO.