Indoor Air Quality Updates
Wilson, D.L. et al., 2015. Comparing Cookstove Usage Measured with Sensors Versus Cell Phone-Based Surveys in Darfur, Sudan. In S. Hostettler, E. Hazbourn, & J.-C. Bolay, eds. Technologies for Development: What is Essential? New York: Springer International Publishing, pp. 211–221.
Three billion people rely on combustion of biomass to cook their food, and the resulting air pollution kills 4 million people annually. Replacing inefficient traditional stoves with “improved cookstoves” may help reduce the dangers of cooking. Therefore analysts, policy makers, and practitioners are eager to quantify adoption of improved cookstoves. In this study, we use 170 instrumented cook- stoves as well as cellphone-based surveys to measure the adoption of free-of-charge Berkeley-Darfur Stoves (BDSs) in Darfur, Sudan where roughly 34,000 BDS have been disseminated.
We estimate that at least 71 % of participants use the stove more than 10 % of days that the sensor was installed on the cookstove. Compared to sensor-measured data, surveyed participants overestimate adoption both in terms of daily hours of cooking and daily cooking events (p < 0.001). Average participants overreport daily cooking hours by 1.2 h and daily cooking events by 1.3 events. These overestimations are roughly double sensor-measured values. Data reported by participants may be erroneous due to difficulty in recollection, courtesy bias, or the desire to keep personal information obscure.
A significant portion of sensors was lost during this study, presumably due to thermal damage from the unexpected commonality of charcoal fires in the BDS; thus pointing to a potential need to redesign the stove to accommodate users’ desire to cook using multiple fuel types. The cooking event detection algorithm seems to perform well in terms of face validity, but a database of cooking logs or witnessed accounts of cooking is absent; the algorithm should be trained against expert-labeled data for the local cooking context to further refine its performance.
Indicators of exposure to household air pollution. WHO Bulletin, May 2015.
Authors: Kendra N Williams, Amanda L Northcross & Jay P Graham
More information could be collected through national surveys to increase awareness and knowledge of the extent and impact of household air pollution. Because the development of specific questions for national surveys is a lengthy process that requires extensive piloting and testing to assure validity and reliability, we do not propose specific questions, but rather summarize categories of information critical for understanding the problem, based on examples from a related field: water, sanitation and hygiene (WASH).
In contrast to the WASH field, no indicator in the DHS or MICS tracks types of cooking apparatus owned or used for cooking. Information on fuel collection is also incomplete. We suggest that additional indicators are needed in the following categories:
- (i) types of cooking apparatus owned;
- (ii) use of cooking apparatus;
- (iii) fuel collection practices;
- (iv) fine particulate matter exposures or household concentrations; and
- (v) fuels used for heating and lighting.
Understanding Impacts of Women’s Engagement in the Improved Cookstove Value Chain in Kenya, 2015.
- Anita V. Shankar, Department of Environmental Health Sciences, Center for Global Clean Air; Bloomberg School of Public Health, Johns Hopkins University
- Mary Alice Onyura, ESVAK Community Development Initiatives
- Jessica Alderman, Envirofit International
In this study, we examine the relative impacts of engaging women entrepreneurs in the clean cooking value chain and its association with overall improved cookstove (ICS) sales and adoption. The overall objectives were to understand the impacts that women can have on sales of ICS when engaged as entrepreneurs and to compare the relative business capacities of newly trained male and female entrepreneurs who received either basic entrepreneurial training or a novel agency-based empowerment training.
Gender and Livelihoods Impacts of Clean Cookstoves in South Asia: Executive Summary, 2015 .
Commissioned by the Global Alliance for Clean Cookstoves. Developed by: Practical Action; Lead Contact: Dr. Ewan Bloomfield, Practical Action
In South Asia, women play a significant and dominant role within the household cooking sector. Generally women do most of the cooking and, therefore, are disproportionately affected by household air pollution (HAP) caused by the inefficient burning of solid biomass cooking fuels. They are also required to spend a significant amount of time and effort collecting the traditionally used biomass fuels, a physically draining task that can take up to 20 or more hours per week.
This study analyzes the gender impacts of clean cooking solutions on households that have adopted them, as well as women’s current and potential involvement in ICS market systems in each of the three South Asian countries. This study focuses primarily on improved biomass cookstoves, but also analyzes the use of other cooking solutions, including kerosene and liquefied petroleum gas (LPG). Efforts have been made to generate recommendations on women’s involvement in ICS value chains that can effectively reach “last mile” households in South Asia.
Biogas fact sheet, 2015. Global Alliance for Clean Cookstoves.
Biogas is a methane rich gas produced through the anaerobic (without air) digestion of organic wastes. It can be generated from animal and kitchen wastes, as well as some crop residues. For cooking and other thermal household tasks, biogas can be used directly in conventional low-pressure gas burners.
Biogas is used for many different applications worldwide. In rural communities, small-scale digesters can provide biogas for single-household cooking and lighting. Large-scale digesters can utilize biogas for electricity production, heat and steam, chemical production, and vehicle fuel.
Africa: 5 Innovations that will Electrify Africa in the Next Decade, April 29, 2015.
Gesper Mndeme is a 31-year old farmer, father, and part-time business student in Tanzania. He used to stumble through the pre-dawn darkness by way of a flickering candle to prepare the morning meal for himself and his daughter, Sunny. A kerosene flame from an old water bottle lit their 200-square-foot hut while emitting plumes of toxic smoke. Now for less than the $1 he used to spend daily on kerosene and candles, he and his daughter enjoy two LED lights, a cell-phone charger, and a radio. The soft sound of local Tanzanian rhythms fills the moist morning air as he prepares cassava and vegetables.
Worldwide, 1.3 billion people live without access to electricity, while another 1 billion experience significant rolling blackouts. Nearly 97% of them live in Sub-Saharan Africa and developing Asia, and lack of reliable electricity creates a massive drain on education, manufacturing, and retail. More than 50 percent of businesses in Sub-Saharan Africa identify electricity as a major constraint to their operation compared with just 27 % citing transportation.
But that will soon change. The confluence of five dynamics will electrify the continent within a decade. These include the rapidly declining price of solar energy, increased battery capacity per dollar, the proliferation of mobile phone commerce, innovative consumer finance techniques, and creative for-profit business models.
Here’s a look at each:
1. Cheaper solar electricity. Swanson’s Law, which states that solar cell prices fall 20% for every doubling in industry capacity, is finally beginning to play out. Lower prices for solar panels in the developed world make this renewable energy competitive with electricity. This competitiveness fuels a virtuous cycle of increased spending on R&D, which further decreases panel prices.
The price per watt of solar electricity has decreased 44% since the end of 2011, and all trends point to even lower costs with economies of scale. Sub-Saharan Africa is ideal for solar energy, as it receives more solar radiation than almost anywhere else in the world. Lack of infrastructure and ineffective public energy bureaucracies make it unlikely that the 85% of Africans off the national grids will ever connect to them. Just as cell phones displaced landlines in the developing world, solar energy will bring electricity to the masses, displacing kerosene and candles.
- Read more in Development Diaries
Household Air Pollution Causes Dose-Dependent Inflammation and Altered Phagocytosis in Human Macrophages
Household Air Pollution Causes Dose-Dependent Inflammation and Altered Phagocytosis in Human Macrophages. American Journal of Respiratory Cell and Molecular Biology, May 2015.
Authors: Jamie Rylance, Duncan G. Fullerton, James Scriven, et al.
We used human alveolar macrophages obtained from healthy Malawian adults exposed naturally to household air pollution and compared them with human monocyte-derived macrophages exposed in vitro to respirable-sized particulates. Cellular inflammatory response was assessed by IL-6 and IL-8 production in response to particulate challenge; phagosomal function was tested by uptake and oxidation of fluorescence-labeled beads; ingestion and killing of Streptococcus pneumoniae and Mycobacterium tuberculosis were measured by microscopy and quantitative culture.
Particulate ingestion was quantified by digital image analysis. We were able to reproduce the carbon loading of naturally exposed alveolar macrophages by in vitro exposure of monocyte-derived macrophages. Fine carbon black induced IL-8 release from monocyte-derived and alveolar macrophages (P < 0.05) with similar magnitude responses (log10 increases of 0.93 [SEM = 0.2] versus 0.74 [SEM = 0.19], respectively). Phagocytosis of pneumococci and mycobacteria was impaired with higher particulate loading.
High particulate loading corresponded with a lower oxidative burst capacity (P = 0.0015). There was no overall effect on killing of M. tuberculosis. Alveolar macrophage function is altered by particulate loading. Our macrophage model is comparable morphologically to the in vivo uptake of particulates. Wood smoke–exposed cells demonstrate reduced phagocytosis, but unaffected mycobacterial killing, suggesting defects related to chronic wood smoke inhalation limited to specific innate immune functions.
Economic cost of the health impact of air pollution in Europe: Clean air, health and wealth, 2015. WHO.
This paper extends the analyses of the most recent WHO, European Union and Organisation for Economic Co-operation and Development research on the cost of ambient and household air pollution to cover all 53 Member States of the WHO European Region.
It describes and discusses the topic of air pollution from a Health in All Policies perspective, reflecting the best available evidence from a health, economics and policy angle and identifies future research areas and policy options.
PM2.5 in household kitchens of Bhaktapur, Nepal, using four different cooking fuels. Atmos Environ, Apr 29, 2015.
Authors: Amod K. Pokhrel, , Michael N. Bates, Jiwan Acharya, Palle Valentiner-Branth, Ram K. Chandyo, Prakash S. Shrestha, Anil K. Raut, Kirk R. Smith
- One of the largest databases of indoor PM2.5 measurements from cookstoves.
- PM2.5 levels were measured in kitchens using low-cost nephelometers.
- The nephelometers results were well correlated with results from gravimetric method.
- Decreasing PM2.5 was associated with biomass, kerosene and then LPG/electric stoves.
- PM2.5 levels in the kitchens with electric stoves were similar to ambient PM2.5 levels.
In studies examining the health effects of household air pollution (HAP), lack of affordable monitoring devices often precludes collection of actual air pollution data, forcing use of exposure indicators, such as type of cooking fuel used. Among the most important pollutants is fine particulate matter (PM2.5), perhaps the best single indicator of risk from smoke exposure. In this study, for one of the first times at scale, we deployed an affordable and robust device to monitor PM2.5 in 824 households in Bhaktapur, Nepal. Four primary cooking fuels were used in roughly equal proportions in these households: electricity (22%), liquefied petroleum gas (LPG) (29%), kerosene (23%), and biomass (26%). PM2.5 concentrations were measured in the kitchens using a light-scattering nephelometer, the UCB-PATS (University of California, Berkeley-Particle and Temperature monitoring System). The major predictors of PM2.5 concentrations in study households were investigated. The UCB-PATS results were well correlated with the gravimetric results (R2=0.84; for all fuels combined).
The mean household PM2.5 concentrations across all seasons of the year were 656 (standard deviation (SD):924) μg/m3 from biomass; 169 (SD: 207) μg/m3 from kerosene; 101 (SD: 130) μg/m3 from LPG; and 80 (SD: 103) μg/m3 from electric stoves. In the multivariate regression of PM2.5 measures, compared with electric stoves, use of LPG, kerosene and biomass stoves were associated with increased indoor PM2.5 concentrations of 65% (95% CI: 38-95%), 146% (103-200%), and 733% (589-907%), respectively. The UCB-PATS performed well in the field. Biomass fuel stoves without flues were the most significant sources of PM2.5, followed by kerosene and then LPG stoves. Outdoor PM2.5, and season influenced indoor PM2.5 levels. Results support careful use of inexpensive light-scattering monitors for monitoring of HAP in developing countries.
The presentations listed below are on the conference presentation archive.
- Ashok Gadgil – How Many Test Replicates Needed to Obtain Useful Data
- Dean Still – The ARC Stoves and Steps to Improve PerformanceDoE
- Jonathan Posner – Multidisciplinary Design of Innovative Natural Draft..DoE
- Ryan Gist – Heart of the Hearth
- Dorothea Otremba – What’s New at GIZ HERA
- Benjamin Sullivan – Real-Time Monitoring of PM from Wood-Fired Cookstoves
- Julien Caubel – A Compact, Inexpensive Black Carbon Sensor for Biomass Cookstove Emissions
- Nelson Byanyima – Stove Testing Experiences at CREEC
- Daniel Wilson – Cookstove Adoption Measured with SUMs in Darfur
- Elisa Derby – USAID/WASHplus Bangladesh and Nepal
- Michelle Kreger – Designing Marketing Trials that Optimize for Stove Adoption and Sustained Usage
- Nextleaf Analytics – Using Wireless Thermal Sensors to Scale Up Forced Draft Stoves
- Pam Jagger – The Challenge of Biomass Reliance for Climate, Environment, Health and Welfare in Malawi
- Praveen Kumar – Dynamics of Sustained Use and Abandonment of Clean Energy Systems in Rural India
- Andre Ndeky – First Stove Camp in French Speaking Africa
- Christa Roth – A Tribute to Paal Wendelbo
- Dale Andreatta – A Few Notes Regarding Sanitation
- Gregory Egan – Bamboo Charcoal Air Freshener
- Paul Anderson – Important Dates in Stove History
- Sebastian Africano – Trees Water People Program Update
- Anamol Pundle – Computational Fluid Dynamic Modeling of a Natural Draft Cookstove
- Dale Andreatta – Rocket Stoves with Extended Fuel Chambers
- Kathleen M. Lask – Simplified Model for Lighting Cone Design
- Kelly Banta – Corrosion Considerations for Metallic Combustors in Low-Cost, Clean Biomass Cookstoves
- Kevin Dischino – Experimental Optimization of Forced Draft for PM 2.5 Emissions Reduction
- Christa Roth – CleanChristian L’Orange – Center for Energy Development and Health CSU
- Michael A. Johnson – Linking Household Energy Use with Indoor Air Quality
- Nordica McCarty – A Holistic Assessment of Village Energy
- Ranyee Chiang – ISO Update
- David Stokes – TECA for Clean Biomass CookstovesDoE
- Tim Theiss – Combustion Materials Durability Relationships for Improved Low-Cost Cookstoves
- Elliot Levine – U.S. Department of Energy’s Cookstove Initiative
- Ranyee Chiang – Choose Your Alliance Topics
- John and Flip Anderson- Rocket Mud Ovens
- Seema Patel – GACC Tools for Evaluating Fuels Impacts and Sustainability
- Kirk Harris – Wonderwerk Strata Combustor
- Paul S. Anderson – Advances in TLUD and Other Micro-GasifiersDoE
- Dean Still – Five Tier 4 Stoves Move Toward the MarketDoE
- Jessica Tryner – Achieving Tier 4 Emissions and Efficiency in Biomass Cookstoves
- John Mitchell – EPA Stepwise
- Sam Bentson – How to Cheat on the WBT
Health and the environment:addressing the health impact of air pollution, April 2015. WHO.
The Executive Board, in its consideration of health and the environment at its 135th session, decided to include the subject on the provisional agenda of the Board at its 136th session.1 At that session the Board considered an earlier version of this report,2 together with a draft resolution.3 The Board then adopted decision EB136(14), in which Member States were encouraged to finalize their work on the draft resolution to enable it to be considered by the Sixty-eighth World Health Assembly.
A preparatory process for the draft resolution, including informal consultations with Member States, is being held between January and May 2015. The present report describes the links between air pollution and health, and outlines some strategies for prevention, control and mitigation of the adverse effects of air pollution on health, including coordinated action between the health and other sectors.
Effect of Indoor air pollution from biomass and solid fuel combustion on symptoms of preeclampsia/eclampsia in Indian women
Effect of Indoor air pollution from biomass and solid fuel combustion on symptoms of preeclampsia/eclampsia in Indian women. Indoor Air. 2015 Jun;25(3):341-52.
Authors: Agrawal S1, Yamamoto S. South Asia Network for Chronic Disease, Public Health Foundation of India, New Delhi, India.
Available evidence concerning the association between indoor air pollution (IAP) from biomass and solid fuel combustion and preeclampsia/eclampsia is not available in developing countries. We investigated the association between exposure to IAP from biomass and solid fuel combustion and symptoms of preeclampsia/eclampsia in Indian women by analyzing cross-sectional data from India’s third National Family Health Survey (NFHS-3, 2005-2006). Self-reported symptoms of preeclampsia/eclampsia during pregnancy such as convulsions (not from fever), swelling of legs, body or face, excessive fatigue or vision difficulty during daylight, were obtained from 39 657 women aged 15-49 years who had a live birth in the previous 5 years. Effects of exposure to cooking smoke, ascertained by type of fuel used for cooking on preeclampsia/eclampsia risk, were estimated using logistic regression after adjusting for various confounders.
Results indicate that women living in households using biomass and solid fuels have two times higher likelihood of reporting preeclampsia/eclampsia symptoms than do those living in households using cleaner fuels (OR = 2.21; 95%: 1.26-3.87; P = 0.006), even after controlling for the effects of a number of potentially confounding factors. This study is the first to empirically estimate the associations of IAP from biomass and solid fuel combustion and reported symptoms suggestive of preeclampsia/eclampsia in a large nationally representative sample of Indian women and we observed increased risk. These findings have important program and policy implications for countries such as India, where large proportions of the population rely on polluting biomass fuels for cooking and space heating. More epidemiological research with detailed exposure assessments and clinical measures of preeclampsia/eclampsia is needed in a developing country setting to validate these findings.
Changing Paradigms in Clean Cooking. EcoHealth, April 2015.
Author: Kirk Smith
The latest Comparative Risk Assessment of the Global Burden of Disease (GBD) estimates that household air pollution (HAP) from solid cooking fuels imposes the largest environmental health burden in the world among all risk factors examined (Lim et al. 2012). With about 4 million premature deaths annually from both the household exposures and the exposures downwind from household contribution to outdoor air pollution (secondhand cooksmoke), HAP is ranked fourth in the world among all the risk factors, even though only about 40% of the world is directly exposed, those in poor countries cooking with biomass or coal (Smith et al. 2014).
There will be changes in these estimates going forward, due to better evidence on relative risks of the current diseases associated with HAP [acute lower respiratory infection (pneumonia) (ALRI), chronic obstructive pulmonary disease (COPD), ischaemic heart disease (IHD), stroke, lung cancer, and cataracts], more accurate exposure estimates, and addition of new diseases for which evidence is suggestive but not yet convincing (e.g., TB, birth outcomes, and cognitive effects), but it seems that HAP has crossed a historical threshold. Regardless whether it is 4, 2, or 6 million premature deaths, HAP is clearly responsible for much ill health among, almost by definition, the least advantaged people in the world. It has joined the gorillas in the room like outdoor air pollution, high BMI, sodium intake, child underweight, and physical inactivity, in the global burden, although somewhat smaller than the three elephants: high blood pressure, alcohol, and smoking. Like all these others, it is not going away easily either in our risk estimates or on the ground.
The health impacts of HAP have been suspected for decades, and a few isolated studies occurred more than a half century back (e.g., Padmavaty and Pathak 1959), but it has only been in the last period that the sufficient evidence has been marshaled to make a systematic case across a range of diseases. Extremely helpful in this task was the development in the recent GBD project of Integrated Exposure Response functions that link the risks of five diseases across four exposure categories of combustion pollution, in order of exposure levels: ambient air pollution, secondhand tobacco smoke, HAP, and active smoking. The same diseases are caused by each, albeit at risk levels commensurate with their quite different exposure levels (Burnett et al. 2014).
Although basic epidemiological and exposure research continues, given the that this threshold has been passed, there is a need now to examine carefully the paradigms behind efforts to ameliorate the situation as intervention research becomes more to the fore. Here I examine the traditional paradigms that have dominated thinking over the last half century and then propose five new ones to help in the future.
Childhood tuberculosis and exposure to indoor air pollution: a systematic review and meta-analysis. The International Journal of Tuberculosis and Lung Disease, May 2015.
Authors: Jafta, N.; Jeena, P. M.; Barregard, L.; Naidoo, R. N.
BACKGROUND: Indoor air pollution (IAP) from environmental tobacco smoke (ETS) and biomass fuel smoke (BMS) poses respiratory health risks, with children and women bearing the major burden.
OBJECTIVES: We used a systematic review and meta-analysis to investigate the relation between childhood tuberculosis (TB) and exposure to ETS and BMS.
METHODS: We searched three databases for epidemiological studies that investigated the association of childhood TB with exposure to ETS and BMS. We calculated pooled estimates and heterogeneity for studies eligible for inclusion in the meta-analysis and stratified studies on ETS by outcome.
RESULTS: Five case-control and three cross-sectional studies were eligible for inclusion in the meta-analysis and quality assessment. Pooled effect estimates showed that exposure to ETS is associated with tuberculous infection and TB disease (OR 1.9, 95%CI 1.4–2.9) among exposed compared to non-exposed children. TB disease in ETS studies produced a pooled OR of 2.8 (95%CI 0.9–4.8), which was higher than the OR for tuberculous infection (OR 1.9, 95%CI 0.9–2.9) for children exposed to ETS compared to non-exposed children. Studies on BMS exposure were too few and too small to permit a conclusion.
CONCLUSION: Exposure to ETS increases the risk of childhood TB disease or tuberculous infection.
Advancing Communication and Behavior Change Strategies for Cleaner Cooking – Announcing a special issue of the Journal of Health Communication: International Perspectives funded by the USAID | TRAction Project.
This special issue presents exciting findings on methods to promote the adoption of clean cooking technologies and fuels. The issue aims to advance our understanding of behavior change related to the technology, the enabling environment, and demand creation. Lessons are intended to inform household energy policy and program strategies. (Link to flyer, pdf)
Guest editors: Jay Graham, Assistant Professor,George Washington University; Sumi Mehta, Director of Research and Evaluation, Global Alliance for Clean Cookstoves; Julia Rosenbaum, Deputy Director, FHI360,USAID/WASHplus Project; Brendon Barnes, Professor, University of Johannesburg.
Advancing Communication and Behavior Change Strategies for Cleaner Cooking | Complete issue |
Impact of indoor air pollution from the use of solid fuels on the incidence of life threatening respiratory illnesses in children in India
Impact of indoor air pollution from the use of solid fuels on the incidence of life threatening respiratory illnesses in children in India. BMC Public Health, Marc 2015.
Authors: Ashish Kumar Upadhyay, Abhishek Singh, et al.
Background – India contributes 24% of the global annual child deaths due to acute respiratory infections (ARIs). According to WHO, nearly 50% of the deaths among children due to ARIs is because of indoor air pollution (IAP). There is insufficient evidence on the relationship between IAP from the use of solid fuels and incidence of life threatening respiratory illnesses (LTRI) in children in India.
Methods – Panel data of children born during 2001–02, from the Young Lives Study (YLS) conducted in India during 2002 and 2006–07 was used to estimate the impact of household use of solid fuels for cooking on LTRI in children. Multivariable two-stage random effects logistic regression model was used to estimate the odds of suffering from LTRI among children from households using solid fuels relative to children from households using other fuels (Gas/Electricity/Kerosene).
Results – Bivariate results indicate that the probability of an episode of LTRI was considerably higher among children from households using solid fuels for cooking (18%) than among children from households using other fuels (10%). Moreover, children from households using solid fuels in both the rounds of YLS were more likely to suffer from one or more than one episode of LTRI compared to children from households using solid fuels in only one round. Two stage random effects logistic regression result shows that children from households using solid fuels were 1.78 (95% CI: 1.05-2.99) times as likely to suffer from LTRI as those from households using other fuels.
Conclusion The findings of this paper provide conclusive evidence on the harmful effects of the use of solid fuels for cooking on LTRI in India. The Government of India must make people aware about the health risks associated with the use of solid fuels for cooking and strive to promote the use of cleaner fuels.
Quantification of climate related emission reductions of Black Carbon and Co-emitted Species due to the replacement of less efficient cookstoves with improved efficiency cookstoves
Quantification of climate related emission reductions of Black Carbon and Co-emitted Species due to the replacement of less efficient cookstoves with improved efficiency cookstoves, March 2015. The Gold Standard.
This methodology is applicable to project activities that introduce efficient cookstove technologies and/or practices or switch from non-renewable to renewable biomass for meeting thermal energy requirements for cooking regimes.
Using objective measures of stove use and indoor air quality to evaluate a cookstove intervention in rural Uganda
Using objective measures of stove use and indoor air quality to evaluate a cookstove intervention in rural Uganda. Energy for Sustainable Development, April 2015.
Authors: Steve Hankey, Kelly Sullivan, et al.
- We recruited 54 households in 6 communities in rural Uganda to study the introduction of a locally manufactured rocket stove.
- We measured PM2.5 (n = 28), CO (n = 34), and stove use (n = 32) before and 1 month after introduction of the stove.
- After introduction of the stove, there were statistically significant reductions in concentrations of PM2.5 but not CO.
- After Ugastove introduction, half of the households primarily used the Ugastove. Most others used the stoves in tandem.
Exposure to combustion byproducts from cooking is a major health concern globally. Alternative stoves may reduce the burden of disease associated with exposure to household air pollution. We subsidized Ugastove-brand rocket stoves to 54 households in six rural Ugandan villages. We monitored kitchen concentrations of fine particles (PM2.5) and carbon monoxide (CO) before and one month after introduction of the Ugastove. Temperature data-loggers were affixed to each Ugastove and to the traditional stove (three‐stone fire) during the 1-month Ugastove acclimation period to record temporal patterns in stove use and adoption. Household surveys were administered to collect household information that may impact stove use or indoor air quality.
PM2.5 kitchen concentrations were 37% lower after introduction of the Ugastove (mean reduction: 0.68 mg/m3; 95% confidence interval [CI]: 0.2–1.2; p < 0.01). Changes in CO concentrations were small (8% lower; mean reduction: 1.4 ppm, 95% CI: – 5.2–7.9) and not statistically significant. During the 1-month acclimation period, 47% of households used primarily the Ugastove, 12% used primarily the three stone fire, and 41% used both stoves in tandem. PM2.5 concentrations were generally lowest in households that used primarily the Ugastove, followed by households that used stoves in tandem and that primarily used a three‐stone fire. In summary, introduction of the Ugastove in 54 rural Ugandan households was associated with modest reductions in kitchen concentrations of PM2.5 but not CO. Objective measures of stove use reveal that short-term stove use varied by household.
Socio-economic determinants of charcoal expenditures in Tanzania: Evidence from panel data. Energy Economics, April 2015.
Authors: Anthony L. D’Agostinoa, Johannes Urpelainena, Alice Xub
- Analysis of Tanzanian panel data on household charcoal consumption
- Urbanization and income increase charcoal consumption
- Household size has no effect on charcoal consumption
Compared to firewood, charcoal is a relatively clean and convenient fuel. Nevertheless, the mass production of charcoal can contribute substantially to deforestation, rendering it imperative to regulate charcoal use. This article uses nationally representative panel data on Tanzania conducted in 2008 and 2010 to examine how charcoal expenditures change over time within any given household. The focus of the analysis will be on identifying certain socio-economic factors that affect charcoal use at the household level. The framing of the analysis on variation in time within each household addresses the omitted variables bias that often undermines inference from comparisons across different households.
We find that while charcoal expenditures increase with household income, the rise in charcoal use with income is relatively gradual. Household size is unrelated to charcoal expenditures, but urban-rural differences in fuel choice are large even though we include household fixed effects in all specifications. In this regard, policymakers and urban planners need to pay particular attention to the role of urbanization in predicting trends in charcoal expenditures in developing countries like Tanzania.
Exposure to Household Air Pollution from Wood Combustion and Association with Respiratory Symptoms and Lung Function in Nonsmoking Women: Results from the RESPIRE Trial, Guatemala
Exposure to Household Air Pollution from Wood Combustion and Association with Respiratory Symptoms and Lung Function in Nonsmoking Women: Results from the RESPIRE Trial, Guatemala. Env Health Perspec, April 2015.
Authors: Daniel Pope, Esperanza Diaz, Tone Smith-Sivertsen, Rolv T. Lie, Per Bakke, John R. Balmes, Kirk R. Smith, and Nigel G. Bruce
Background: With 40% of the world’s population relying on solid fuel, household air pollution (HAP) represents a major preventable risk factor for COPD (chronic obstructive pulmonary disease). Meta-analyses have confirmed this relationship; however, constituent studies are observational, with virtually none measuring exposure directly.
Objectives: We estimated associations between HAP exposure and respiratory symptoms and lung function in young, nonsmoking women in rural Guatemala, using measured carbon monoxide (CO) concentrations in exhaled breath and personal air to assess exposure.
Methods: The Randomized Exposure Study of Pollution Indoors and Respiratory Effects (RESPIRE) Guatemala study was a trial comparing respiratory outcomes among 504 women using improved chimney stoves versus traditional cookstoves. The present analysis included 456 women with data from postintervention surveys including interviews at 6, 12, and 18 months (respiratory symptoms) and spirometry and CO (ppm) in exhaled breath measurements. Personal CO was measured using passive diffusion tubes at variable times during the study. Associations between CO concentrations and respiratory health were estimated using random intercept regression models.
Results: Respiratory symptoms (cough, phlegm, wheeze, or chest tightness) during the previous 6 months were positively associated with breath CO measured at the same time of symptom reporting and with average personal CO concentrations during the follow-up period. CO in exhaled breath at the same time as spirometry was associated with lower lung function [average reduction in FEV1 (forced expiratory volume in 1 sec) for a 10% increase in CO was 3.33 mL (95% CI: –0.86, –5.81)]. Lung function measures were not significantly associated with average postintervention personal CO concentrations.
Conclusions: Our results provide further support for the effects of HAP exposures on airway inflammation. Further longitudinal research modeling continuous exposure to particulate matter against lung function will help us understand more fully the impact of HAP on COPD.