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WHO Indoor air quality guidelines on household fuel combustion: Strategy implications of new evidence on interventions and exposure-risk functions

27 August 2014 11:56 (America/New_York)

WHO Indoor air quality guidelines on household fuel combustion: Strategy implications of new evidence on interventions and exposure-risk functions. Atmospheric Environment, 27 August 2014, In Press.

Nigel Brucea, b, , , Dan Popea, Eva Rehfuessc, Kalpana Balakrishnand, Heather Adair-Rohanib, Carlos Dorab
a Department of Public Health and Policy, University of Liverpool, UK
b Department of Public Health, Environmental and Social Determinants of Health, World Health Organisation, Geneva
c Institute for Medical Informatics, Biometry and Epidemiology, Ludwig-Maximilians-University, Munich, Germany
d Department of Environmental Health Engineering, Sri Ramachandra University, Chennai, India

• New WHO air quality guidelines will address household air pollution (HAP).
• Action on HAP could lower risk of multiple child and adult diseases by 20-50%.
• New evidence shows levels at or below 35 μg/m3 PM2.5 (WHO IT-1) are needed.
• Most improved solid fuel stoves result in PM2.5 levels well above IT-1.
• Intervention strategy must shift towards accelerating access to clean fuels.

Background - 2.8 billion people use solid fuels as their primary cooking fuel; the resulting high levels of household air pollution (HAP) were estimated to cause more than 4 million premature deaths in 2012. The people most affected are among the world’s poorest, and past experience has shown that securing adoption and sustained use of effective, low-emission stove technologies and fuels in such populations is not easy. Among the questions raised by these challenges are (i) to what levels does HAP exposure need to be reduced in order to ensure that substantial health benefits are achieved, and (ii) what intervention technologies and fuels can achieve the required levels of HAP in practice? New WHO air quality guidelines are being developed to address these issues.

Aims – To address the above questions drawing on evidence from new evidence reviews conducted for the WHO guidelines.

Methods – Discussion of key findings from reviews covering (i) systematic reviews of health risks from HAP exposure, (ii) newly developed exposure-response functions which combine combustion pollution risk evidence from ambient air pollution, second-hand smoke, HAP and active smoking, and (iii) a systematic review of the impacts of solid fuel and clean fuel interventions on kitchen levels of, and personal exposure to, PM2.5 and carbon monoxide (CO).

Findings – Evidence on health risks from HAP suggest that controlling this exposure could reduce the risk of multiple child and adult health outcomes by 20-50%. The new integrated exposure-response functions (IERs) indicate that in order to secure these benefits, HAP levels require to be reduced to the WHO IT-1 annual average level (35 μg/m3 PM2.5), or below. The second review found that, in practice, solid fuel ‘improved stoves’ led to large percentage and absolute reductions, but post-intervention kitchen levels were still very high, at several hundreds of μg/m3 of PM2.5, although most solid fuel stove types met the WHO 24-hr average guideline for CO of 7 mg/m3 Clean fuel user studies were few, but also did not meet IT-1 forPM2.5, likely due to a combination of continuing multiple stove and fuel use, other sources in the home (e.g. kerosene lamps), and pollution from neighbours and other outdoor sources.

Conclusions – Together, this evidence implies there needs to be a strategic shift towards more rapid and widespread promotion of clean fuels, along with efforts to encourage more exclusive use and control other sources in and around the home. For households continuing to rely on solid fuels, the best possible low-emission solid fuel stoves should be promoted, backed up by testing and in-field evaluation.

Highway proximity and black carbon from cookstoves as a risk factor for higher blood pressure in rural China

27 August 2014 11:18 (America/New_York)

Highway proximity and black carbon from cookstoves as a risk factor for higher blood pressure in rural China. Proc Natl Acad Sci U S A. 2014 Aug 25.

Baumgartner J1, Zhang Y2, Schauer JJ3, Huang W2, Wang Y2, Ezzati M4.
1Institute for Health and Social Policy and Department of Epidemiology, Biostatistics, and Occupational Health, McGill University, Montreal, QC, Canada H3A 1A3; Institute on the Environment, University of Minnesota, St. Paul, MN 55108;
2College of Resources and Environment, University of Chinese Academy of Sciences, Beijing 100049, China;
3Environmental Chemistry and Technology Program, Department of Civil and Environmental Engineering, University of Wisconsin-Madison, Madison, WI 53706; and.
4MRC-PHE Centre for Environment and Health, Department of Epidemiology and Biostatistics, School of Public Health, Imperial College London, London W2 1PG, United Kingdom.

Air pollution in China and other parts of Asia poses large health risks and is an important contributor to global climate change. Almost half of Chinese homes use biomass and coal fuels for cooking and heating. China’s economic growth and infrastructure development has led to increased emissions from coal-fired power plants and an expanding fleet of motor vehicles. Black carbon (BC) from incomplete biomass and fossil fuel combustion is the most strongly light-absorbing component of particulate matter (PM) air pollution and the second most important climate-forcing human emission. PM composition and sources may also be related to its human health impact. We enrolled 280 women living in a rural area of northwestern Yunnan where biomass fuels are commonly used. We measured their blood pressure, distance from major traffic routes, and daily exposure to BC (pyrolytic biomass combustion), water-soluble organic aerosol (organic aerosol from biomass combustion), and, in a subset, hopane markers (motor vehicle emissions) in winter and summer. BC had the strongest association with systolic blood pressure (SBP) (4.3 mmHg; P < 0.001), followed by PM mass and water-soluble organic mass. The effect of BC on SBP was almost three times greater in women living near the highway [6.2 mmHg; 95% confidence interval (CI), 3.6 to 8.9 vs. 2.6 mmHg; 95% CI, 0.1 to 5.2]. Our findings suggest that BC from combustion emissions is more strongly associated with blood pressure than PM mass, and that BC’s health effects may be larger among women living near a highway and with greater exposure to motor vehicle emissions.

Sustained high incidence of injuries from burns in a densely populated urban slum in Kenya: An emerging public health priority.

27 August 2014 11:13 (America/New_York)

Sustained high incidence of injuries from burns in a densely populated urban slum in Kenya: An emerging public health priority. Burns. 2014 Sep;40(6):1194-200.

Authors: Wong JM1, Nyachieo DO1, Benzekri NA1, Cosmas L1, Ondari D1, Yekta S2, Montgomery JM1, Williamson JM1, Breiman RF3.
1Global Disease Detection Division, Center for Global Health, Centers for Disease Control and Prevention (CDC), Nairobi, Kenya and the Kenya Medical Research Institute (KEMRI)-CDC Research Collaboration.
2Division of Plastic and Reconstructive Surgery, University of Toronto, Toronto, ON, Canada.
3Global Disease Detection Division, Center for Global Health, Centers for Disease Control and Prevention (CDC), Nairobi, Kenya and the Kenya Medical Research Institute (KEMRI)-CDC Research Collaboration. Electronic address:

INTRODUCTION: Ninety-five percent of burn deaths occur in low- and middle-income countries (LMICs); however, longitudinal household-level studies have not been done in urban slum settings, where overcrowding and unsafe cook stoves may increase likelihood of injury.

METHODS: Using a prospective, population-based disease surveillance system in the urban slum of Kibera in Kenya, we examined the incidence of household-level burns of all severities from 2006-2011.

RESULTS: Of approximately 28,500 enrolled individuals (6000 households), we identified 3072 burns. The overall incidence was 27.9/1000 person-years-of-observation. Children <5 years old sustained burns at 3.8-fold greater rate compared to (p<0.001) those ≥5 years old. Females ≥5 years old sustained burns at a rate that was 1.35-fold (p<0.001) greater than males within the same age distribution. Hospitalizations were uncommon (0.65% of all burns).

CONCLUSIONS: The incidence of burns, 10-fold greater than in most published reports from Africa and Asia, suggests that such injuries may contribute more significantly than previously thought to morbidity in LMICs, and may be increased by urbanization. As migration from rural areas into urban slums rapidly increases in many African countries, characterizing and addressing the rising burden of burns is likely to become a public health priority.

Factors Influencing Household Uptake of Improved Solid Fuel Stoves in Low- and Middle-Income Countries: A Qualitative Systematic Review

19 August 2014 10:37 (America/New_York)

Factors Influencing Household Uptake of Improved Solid Fuel Stoves in Low- and Middle-Income Countries: A Qualitative Systematic Review. Int. J. Environ. Res. Public Health, Aug 2014.

Authors: Stanistreet Debbi 1,*, Puzzolo Elisa 1, Bruce Nigel 1, Pope Dan 1 and Rehfuess Eva 2
1 Department of Public Health and Policy, Institute of Psychology, Health and Society, Whelan Building, University of Liverpool, Liverpool L69 3GB, UK; E-Mails: (P.E.); (B.N.); (P.D.)
2 Institute for Medical Informatics, Biometry and Epidemiology, University of Munich, Marchioninistr. 15, Munich 81377, Germany; E-Mail:
* Author to whom correspondence should be addressed; E-Mail:; Tel.: +44-151-794-5583.

Abstract: Household burning of solid fuels in traditional stoves is detrimental to health, the environment and development. A range of improved solid fuel stoves (IS) are available but little is known about successful approaches to dissemination. This qualitative systematic review aimed to identify factors that influence household uptake of IS in low- and middle-income countries. Extensive searches were carried out and studies were screened and extracted using established systematic review methods. Fourteen qualitative studies from Asia, Africa and Latin-America met the inclusion criteria. Thematic synthesis was used to synthesise data and findings are presented under seven framework domains.

Findings relate to user and stakeholder perceptions and highlight the importance of cost, good stove design, fuel and time savings, health benefits, being able to cook traditional dishes and cleanliness in relation to uptake. Creating demand, appropriate approaches to business, and community involvement, are also discussed. Achieving and sustaining uptake is complex and requires consideration of a broad range of factors, which operate at household, community, regional and national levels. Initiatives aimed at IS scale up should include quantitative evaluations of effectiveness, supplemented with qualitative studies to assess factors affecting uptake, with an equity focus.

CAPS Study – An advanced cookstove intervention to prevent pneumonia in children under 5 years old in Malawi: a cluster randomised controlled trial

19 August 2014 10:32 (America/New_York)

Liverpool School of Tropical Medicine - CAPS Study: An advanced cookstove intervention to prevent pneumonia in children under 5 years old in Malawi: a cluster randomised controlled trial.


  • Malawi has one of the highest rates of death among infants and the under fives (69 and 110 per 1000 live births respectively in 2009) despite having made progress towards meeting the Millennium Development Goal of reducing child mortality.
  • Pneumonia is the leading cause of death and one of the commonest causes of morbidity: around 300 per 1000 children under the age of 5 are diagnosed with pneumonia every year.
  • Exposure to smoke produced when biomass fuels (animal or plant material) are burned in open fires is a major avoidable risk factor for pneumonia.
  • In Malawi, where at least 95% of households depend on biomass as their main source of fuel, biomass smoke exposure is likely to be responsible for a substantial burden of this disease.
  • Smoke from burning biomass in open fires also causes other health problems including chronic lung disease, lung cancer, heart disease, stillbirth and low birth weight; it is also thought to be an important driver of global climate change.
  • The problem of biomass smoke exposure is seen across Africa where around 700 million people burn biomass fuels to provide energy for cooking, heating and lighting.
  • The problem extends right around the globe where around half the worlds population are dependent on biomass fuels for their day-to-day energy requirements.
  • Around 4 million people die every year around the world from the effects of biomass smoke.


  • There are now particularly efficient biomass-burning cookstoves that substantially reduce smoke emissions and exposures.
  • Some of the more advanced biomass-burning cookstoves reduce emissions by as much as 90% by incorporating technologies (e.g. fans) that improve combustion efficiency.
  • Other ways of reducing biomass fuel use and smoke exposure include cleaner fuels, better ventilation and changes in cooking behavior.
  • Access to smoke exposure reduction technologies is limited by poverty in much of the developing world.
  • The Global Alliance for Clean Cookstoves (GACC) was launched in 2010 to tackle the lack of access to clean affordable energy through public-private partnerships.
  • A central aim of the alliance is for 100 million homes to adopt clean and efficient stoves and fuels by 2020.


  • The trial will be conducted in rural Malawi.
  • 150 villages will be randomly assigned to an intervention or control group.
  • In the intervention villages, all households with a child up to the age of 4.5 years will receive two Philips fan-assisted stoves to fully replace their traditional cooking methods (mainly open fires).
  • In the control villages, all households with a child up to the age of 4.5 years will continue with their traditional cooking methods. Included villages will stay in the study for 2 years.
  • The main outcome of interest is pneumonias in children under 5 years of age.
  • Other outcomes include measures of air pollution and economic and social impacts of the stoves.


EPA/Winrock Webinar – Results from CCT Studies and Stove Design and Performance Testing Workshops in Vietnam, Mexico, and Nepal

19 August 2014 10:26 (America/New_York)

EPA/Winrock Webinar – Results from CCT Studies and Stove Design and Performance Testing Workshops in Vietnam, Mexico, and Nepal, July 29, 2014.

In 2012 and 2013 Aprovecho Research Center, with support from the U.S. EPA and Winrock International, conducted Controlled Cooking Test (CCT) field studies and provided technical training for organizations working to promote cleaner, more efficient cooking technologies in Vietnam (2012), Mexico (2013), and Nepal (2013). On July 2, 2014 Winrock and the U.S. EPA hosted a webinar to present results and lessons learned from the studies and information about how these results can inform and improve cookstove design, performance and use. The webinar also provided context and outcomes from the regional technical capacity building workshops that complemented each field study. Mike Hatfield presented on behalf of Aprovecho Research Center.

Perspectives in Household Air Pollution Research: Who Will Benefit from Interventions?

12 August 2014 12:21 (America/New_York)

Perspectives in Household Air Pollution Research: Who Will Benefit from Interventions? Curr Envir Health Rpt, July 2014.

Authors: Maggie L. Clark & Jennifer L. Peel

Despite increasing recognition surrounding this global environmental health problem, much remains to be elucidated regarding exposure response relationships, particularly among potentially susceptible population subgroups. Given that many of the communities most affected by household air pollution exposures also experience elevated exposures to poverty, psychosocial stressors, other environmental pollutants, and comorbid conditions, research needs to correctly specify risks due to these potentially interacting risk factors. Although suggestive evidence exists for differential improvements in health following reductions in ambient air pollution concentrations among specific subgroups, the question remains as to who will benefit and to what extent from efforts to reduce exposures to emissions from household solid fuel combustion. The ability to know what to expect from cookstove interventions and to accurately describe the presence of distinct subgroup responses is crucial to reduce uncertainty and to encourage policy makers to enact change.

Study delves into Nepal’s kitchen hazards

12 August 2014 12:12 (America/New_York)

Study delves into Nepal’s household hazardsNic White, Medical Press, Aug 8, 2014

A pilot study of Nepalese kitchens aims to improve public health and reduce burn injuries in the poorest neighbourhoods of South Asia, a UWA burn researcher says.

Burn Injury Research Unit Assistant Professor Hilary Wallace says 75 per cent of burns in South Asia occur in the home, mostly in the kitchen, and targeted education and financial support interventions could help save many lives.

“What happens in the kitchen can improve or undermine public health,” she says.

“In many of these poverty-stricken areas, burns are more common than AIDS or tuberculosis.”

Dr Wallace says the study will use community volunteers to locate the most at-risk households, interview them to identify potential hazards in their homes and then deliver tailor-made interventions.

“This holistic approach doesn’t just focus on one problem, it looks at domains like the cooking process instead—which might be harmful for lungs as well as risky for burns,” she says.

Dr Wallace says risk factors could include open biomass fires, uncovered drinking water, hazardous electrical wiring, children playing close to cooking stoves and fires, storage of food, sanitation and hygiene, and cooking and diet practices.

“Cooking is often done on the floor—flames and pots of boiling liquid easily accessible. Flames catch the edge of women’s saris and children knock pots over,” she says.

Exploding kerosene and gas cylinders are particularly devastating but are routinely stored inside because of the likelihood of theft if stored outside.

Cheap and effective anti-theft devices could help this issue, but cylinders may also be bad quality or reused.

Dr Wallace says some 20 per cent of burns, particularly to women, are self inflicted.

“In South Asia there is a lack of social safety nets or other means to cope with crises, and people can find themselves in a situation they feel is unbearable,” she says.

Dr Wallace says the interventions could range from simple advice about better cooking, lighting and heating practices to financial assistance through community-based savings and credit organisations to buy safer technology like improved cookstoves.

“There will be other domains around food preparation, sanitation, water quality, heating and lighting, electricity and storage of flammable liquids and poisons,” she says.

The volunteers will return at regular intervals to support the women to implement the changes.

Dr Wallace says the interventions will be followed up with larger randomised controlled trials to see what approaches improve issues like respiratory disease, diarrhoea and burn injury.


Adherence to reduced-polluting biomass fuel stoves improves respiratory and sleep symptoms in children

12 August 2014 12:07 (America/New_York)

Adherence to reduced-polluting biomass fuel stoves improves respiratory and sleep symptoms in children. BMC Pediatrics 2014, 14:12.

Roberto A Accinelli, et al. Corresponding authors: Roberto A Accinelli

Background – Symptoms of sleep apnea are markedly increased in children exposed to smoke from biomass fuels and are reduced by kitchen stoves that improve indoor biomass pollution. However, the impact of adherence to the use of improved stoves has not been critically examined.

Methods – Sleep-related symptom questionnaires were obtained from children <15 years of age in 56 families residing in the communities of Lliupapuquio, Andahuaylas province in Peru before and 2 years after installation of less-polluting Inkawasi cooking stoves.

Results – 82 children with lifetime exposures to indoor fuel pollution were included. When compared to those alternating between both types of stoves or those using traditional stoves only, those children who exclusively used Inkawasi cooking stoves showed significant improvements in sleep and respiratory related symptoms, but some minor albeit significant improvements occurred when both stoves were concomitantly used.

Conclusions- Improvements in respiratory and sleep-related symptoms associated with elevated indoor biomass pollution occur only following implementation and exclusive utilization of improved kitchen stoves.

World Bank – Tracking Access to Nonsolid Fuel for Cooking

12 August 2014 12:02 (America/New_York)

Tracking Access to Nonsolid Fuel for Cooking, 2014.

Ghosh Banerjee, Sudeshna; Portale, Elisa; Adair-Rohani, Heather; Bonjour, Sophie. World Bank.

The World Health Organization estimates that in 2012 about 4.3 million deaths occurred because of exposure to household air pollution caused by smoke from the incomplete combustion of fuels such as wood, coal, and kerosene. Inefficient energy use in the home also poses substantial risks to safety, causing burns and injuries across the developing world. To support the achievement of these goals, a starting point must be set, indicators developed, and a framework established to track those indicators until 2030.

The World Bank and International Energy Agency have led a consortium of 15 international agencies to produce data on access to nonsolid fuel for the SE4ALL Global Tracking Framework. Launched in 2013, the framework defines access to modern cooking solutions is as the use of nonsolid fuels for the primary method of cooking. Nonsolid fuels include (i) liquid fuels (for example, kerosene, ethanol, or other biofuels), (ii) gaseous fuels (such as natural gas, LPG, and biogas), and (iii) electricity. These are in contrast to solid fuels such as (i) traditional biomass (wood, charcoal, agricultural residues, and dung), (ii) processed biomass (pellets, briquettes); and (iii) other solid fuels (such as coal and lignite).

Experimental Evidence on Improved Cooking Stoves in Rural Senegal

8 August 2014 12:19 (America/New_York)

The Intensive Margin of Technology Adoption: Experimental Evidence on Improved Cooking Stoves in Rural Senegal, 2014.

Gunther Bensch; Jörg Peters. Ruhr-Universität Bochum (RUB), Department of Economics.

This paper evaluates take-up and impacts of low-cost improved stoves through a randomized controlled trial. The randomized stove is primarily designed to curb fi rewood consumption but not smoke emissions. Nonetheless, we find considerable effects not only on firewood consumption, but also on smoke exposure and smoke-related disease symptoms – induced by behavioural changes at the intensive margin affecting outside cooking and cooking time due to the new stove.

Affordability for sustainable energy development products

8 August 2014 12:06 (America/New_York)

Affordability for sustainable energy development products. Applied Energy, Volume 132, 1 November 2014, Pages 308–316

Paul H. Riley. The University of Nottingham, Department of Electrical and Electronic Engineering, Nottingham NG7 2RD, UK

Clean burning products, for example cooking stoves, can reduce household air pollution (HAP), which prematurely kills 3.5 million people each year. By careful selection of components into a product package with micro-finance used for the capital payment, barriers to large-scale uptake of products that remove HAP are reduced. Such products reduce smoke from cooking and the lighting from electricity produced, eliminates smoke from kerosene lamps. A bottom-up financial model, that is cognisant of end user social needs, has been developed to compare different products for use in rural areas of developing countries. The model is freely available for use by researchers and has the ability to assist in the analysis of changing assumptions. Business views of an individual villager, the village itself and a country view are presented.

The model shows that affordability (defined as the effect on household expenses as a result of a product purchase) and recognition of end-user social needs are as important as product cost. The effects of large-scale deployment (greater that 10 million per year) are described together with level of subsidy required by the poorest people. With the assumptions given, the model shows that pico-hydro is the most cost effective, but not generally available, one thermo-acoustic technology option does not require subsidy, but it is only at technology readiness level 2 (NASA definition) therefore costs are predicted and very large investment in manufacturing capability is needed to meet the cost target. Thermo-electric is currently the only technology that can be used worldwide every day of the year and is available without research. However, it is not yet self-financing and therefore requires subsidy or diversion of more household income to be affordable. A combination of photovoltaic and clean cookstove may be suitable in areas where sufficient solar radiation is available on most days. Affordability is shown to be highly dependent on the income that can be derived from carbon credits.

Human urinary mutagenicity after wood smoke exposure during traditional temazcal use

8 August 2014 11:57 (America/New_York)

Human urinary mutagenicity after wood smoke exposure during traditional temazcal use. Mutagenesis, Advance Access published August 1, 2014.

Alexandra S. Long*, Christine L. Lemieux1, et al.

This study examined the urinary mutagenicity in 19 indigenous Mayan families from the highlands of Guatemala who regularly use temazcales (N = 32), as well as control (unexposed) individuals from the same population (N = 9). Urine samples collected before and after temazcal exposure were enzymatically deconjugated and extracted using solid-phase extraction. The creatinine-adjusted mutagenic potency of urine extracts was assessed using the plate incorporation version of the Salmonella mutagenicity assay with strain YG1041 in the presence of exogenous metabolic activation. The post-exposure mutagenic potency of urine
extracts were, on average, 1.7-fold higher than pre-exposure samples (P < 0.005) and also significantly more mutagenic than the control samples (P < 0.05). Exhaled carbon monoxide (CO) was ~10 times higher following temazcal use (P < 0.0001), and both CO level and time spent in temazcal were positively associated with urinary mutagenic potency (i.e. P < 0.0001 and P = 0.01, respectively). Thus, the wood smoke exposure associated with temazcal use contributes to increased excretion of conjugated mutagenic metabolites. Moreover, urinary mutagenic potency is correlated with other metrics of exposure (i.e. exhaled CO, duration of exposure). Since urinary mutagenicity is a biomarker associated with genetic damage, temazcal use may therefore be expected to contribute to an increased risk of DNA damage and mutation, effects associated with the initiation of cancer.

Duke University – Cleaning up the act of cooking (Video)

8 August 2014 11:47 (America/New_York)

Improved cook stoves (ICS) have the potential to deliver triple benefits: health and time savings, reduced deforestation, and reduced emissions of black carbon, a significant short-term contributor to global climate change. This video highlights a Duke University research study that aims to better understand the diffusion of ICS technologies in Uttarakhand, India.

Tuberculosis risk from exposure to solid fuel smoke: a systematic review and meta-analysis

8 August 2014 11:44 (America/New_York)

Tuberculosis risk from exposure to solid fuel smoke: a systematic review and meta-analysis. J Epidemiol Community Health. 2014 Jul 31.

Kurmi OP1, Sadhra CS2, Ayres JG3, Sadhra SS3.

BACKGROUND: Studies, particularly from low-income and middle-income countries, suggest that exposure to smoke from household air pollution (HAP) may be a risk factor for tuberculosis. The primary aim of this study was to quantify the risk of tuberculosis from HAP and explore bias and identify possible causes for heterogeneity in reported effect sizes.

METHODS: A systematic review was conducted from original studies. Meta-analysis was performed using a random effects model, with results presented as a pooled effect estimate (EE) with 95% CI. Heterogeneity between studies was assessed.

RESULTS: Twelve studies that considered active tuberculosis and reported adjusted effect sizes were included in the meta-analyses. The overall pooled EE (OR, 95% CI) showed a significant adverse effect (1.43, 1.07 to 1.91) and with significant heterogeneity between studies (I2=70.8%, p<0.001). When considering studies of cases diagnosed microbiologically, the pooled EE approached significance (1.26, 0.95 to 1.68). The pooled EE (OR, 95% CI) was significantly higher among those exposed only to biomass smoke (1.49, 1.08 to 2.05) when compared with the use of kerosene only (0.70, 0.13 to 3.87). Similarly, the pooled EE among women (1.61, 0.73 to 3.57) was greater than when both genders were combined (1.39, 1.01 to 1.92). There was no publication bias (Egger plot, p=0.136). Significant heterogeneity was observed in the diagnostic criteria for tuberculosis (coefficient=0.38, p=0.042).

CONCLUSIONS: Biomass smoke is a significant risk factor for active tuberculosis. Most of the studies were small with limited information on measures of HAP.

Maximizing the benefits of improved cookstoves: moving from acquisition to correct and consistent use

8 August 2014 11:27 (America/New_York)

Maximizing the benefits of improved cookstoves: moving from acquisition to correct and consistent useGlobal Health: Science and Practice, Advance Access, 2014.

Authors: Anita Shankar, Michael Johnson, Ethan Kay, Raj Pannu, Theresa Beltramo, Elisa Derby, Stephen Harrell, Curt Davis, Helen Petach

ICS must meet consumer needs and preferences if they are to lead to correct and consistent use and to successfully displace traditional stoves. This is also necessary for reducing household air pollution and fuel consumption, and therefore providing maximum health and environmental benefits.However, consumer needs and preferences are complex and are influenced by many contextual and social factors that require a deep understanding of culture, going beyond technology and economics.Successful ICS business models will need to be sensitive to cultural practices in both the design of the product and marketing strategies.Key considerations that can aid in large-scale ICS adoption include:

Recognition that stove adoption does notequate with stove acquisition and that long-term consistent and continuous userequires consumer buy-in and understanding of the value proposition that ICS can provide

  • Marketing campaigns that engage the consumer by identifying key attributes of importance to the consumer, rather than long lists of attributes that do not necessarily influence the consumer’s decision
  • Ensuring effective user engagement by including demonstrations, training, and post-sales support
  • Addressing intra-household gender dynamics to enhance equity in purchasing decisions
  • Including women more effectively throughout the cookstove value chain by improving both resources and agency-based support
  • Identification and respect for the cultural significance of cooking food
  • Understanding the actual-use scenarios of the stove (for example, boiling water for teaversus frying flat breads)

An annotated bibliography of July 2014 cookstove/HAP studies

30 July 2014 10:44 (America/New_York)

An Annotated Bibliography of July 2014 Peer-Review  Cookstove/HAP Studies

Below are citations, abstracts and links to seven peer-review July 2014 studies on cookstoves and household air pollution.

The impact of the household decision environment on fuel choice behavior, Energy Economics, Volume 44, July 2014. Link:
Authors: Bianca van der Kroon, Roy Brouwer, Pieter J.H. van Beukering,

Consumer preferences for fuels and alternative cookstove technologies in Kenya are examined, focusing on household internal and external determinants driving choice behavior in a choice experiment. The potential for a transition towards cleaner and more efficient fuels and technologies is assessed by zooming in on three fuel-stove combinations. We find substantial demand and positive willingness to pay for the fuel-stove combinations in three locations representing different decision environments. Demand is significantly higher in the peri-urban and the resource abundant rural location than in the resource scarce rural location. The presence of better developed consumer markets for fuels in these locations functions as an important driver for cookstove adoption. Although charcoal and ethanol stoves are preferred over improved firewood stoves, continued firewood usage is expected. Energy switching behavior cannot be substantiated. Instead, energy stacking is more likely, where charcoal and ethanol add to and extend a household’s energy portfolio.

Carbon monoxide concentrations in outdoor wood-fired kitchens in Ouagadougou, Burkina Faso-implications for women’s and children’s health. Environ Monit Assess, July 2014. Link:
Authors: Thorsson S, Holmer B, et al.

We examined cooking habits and self-reported health in 31 households with outdoor open wood fires in Ouagadougou, Burkina Faso, using structured interviews. On average, CO concentrations were 43 % higher in kitchens located in closed yards than in those located in open yards, showing that fireplace location affected the levels. Eye irritation and coughing among women and children were reported by 30 % of the households. Based on previously reported relations between CO concentrations and fine particles (<2.5 μm), the exposure to biomass smoke appears to be high enough to pose a considerable health risk among women and children in households with outdoor open wood fires. The results suggest that burning should be limited between sunset and dawn and in areas with limited ventilation to reduce pollutions levels.

A Cross-Sectional Study of Household Biomass Fuel Use among a Periurban Population in Malawi. Ann Am Thorac Soc July 2014. Abstract.
Authors: Piddock KC, et al.

This large cross-sectional study has identified extensive use of biomass fuels in a typical sub-Saharan Africa periurban population in which women and people of lower socioeconomic status are disproportionately affected. Biomass fuel use is likely to be a major driver of existing communicable respiratory disease and the emerging noncommunicable disease (especially respiratory and cardiovascular) epidemic in this region. Our data will help inform the rationale for specific intervention studies and the development of appropriately targeted public health strategies to tackle this important and poverty-related global health problem.

Improved test method for evaluation of bio-mass cook-stoves, Energy, Volume 71, 15 July 2014. Link:
Authors: P. Raman, N.K. Ram, J. Murali,

More than two-thirds of the world’s population is relying on biomass fuel to meet their cooking and heating energy-requirements. Traditional biomass stoves operate at low efficiency and cause severe health problems and pollute the environment. Due to higher quantity of fuel use, these cookstoves increase the burden on fuel management. Several test protocols are being used across the world for evaluating the performance of cookstoves. One of the major challenges of existing protocols is to narrow down the gap between the test results obtained under lab conditions and actual cooking conditions. Hence, there is a need to evolve an improved test method that can reflect the stove performance under field conditions. This paper is aimed to reduce the gaps in test methodology in such a manner that the test results obtained in the lab are comparable with the results of actual cooking carried out in the kitchen.

Personal and Indoor PM2.5 Exposure from Burning Solid Fuels in Vented and Unvented Stoves in a Rural Region of China with a High Incidence of Lung Cancer. Env Sci Technol, Jul 17, 2014.
Authors: Hu W, Reiss B, et al.

The combustion of biomass and coal is the dominant source of household air pollution (HAP) in China, and contributes significantly to the total burden of disease in the Chinese population. Mixed effect models indicated that fuel type, ventilation, number of windows, season, and burning time per stove were the main factors related to personal PM2.5 exposure. Lower PM2.5 among vented stoves compared with unvented stoves and firepits is of interest as it parallels the observation of reduced risks of malignant and nonmalignant lung diseases in the region.

Emission of metals from pelletized and uncompressed biomass fuels combustion in rural household stoves in china. Sci Rep, July 8, 2014.
Authors: Zhang W, Tong Y, et al.

Effort of reducing CO2 emissions in developing countries may require an increasing utilization of biomass fuels. Biomass pellets seem well-suited for residential biomass markets. However, there is limited quantitative information on pollutant emissions from biomass pellets burning, especially those measured in real applications. In this study, biomass pellets and raw biomass fuels were burned in a pellet burner and a conventional stove respectively, in rural households, and metal emissions were determined. This study found that moisture, volatile matter and modified combustion efficiency were the important factors affecting metal emissions. Comparisons of the mass-based and task-based EFs found that biomass pellets produced higher metal emissions than the same amount of raw biomass. However, metal emissions from pellets were not higher in terms of unit energy delivered.

Effect of Indoor Air Pollution from Biomass and Solid fuel Combustion on Symptoms of Preeclampsia/Eclampsia in Indian Women. Indoor Air, July 2014.
Authors: Agrawal S, Yamamoto S.

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, 2005-06). Results indicate that women living in households using biomass fuels have two times higher likelihood of preeclampsia/eclampsia symptoms than do those living in households using cleaner fuels, even after controlling for the effects of a number of potentially confounding factors. We observed increased risk of preeclampsia/eclampsia with exposure to IAP from biomass and solid fuel combustion in a large nationally representative sample of Indian women. 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.

Indonesian Clean Cookstoves Alliance

21 July 2014 15:02 (America/New_York)


Indonesia Clean Cookstoves Alliance (ICCA) was established to support the Indonesia Clean Stove Initiative (CSI), a program initiated by the Directorate of Bioenergy, Directorate General of New, Renewable Energy, and Energy Conservation,Ministry of Energy and Mineral Resources. ICCA will serve as a platform, for all parties concerned with the issue of Household Air Pollution, to exchange and share information, knowledge, experience, technology, in the effort of scaling up household access to clean cooking solutions. ICCA was formed with support from the World Bank and the Directorate of Bioenergy, Ministry of Energy and Mineral Resources, and with funding support provided by the Australian International Development Aid (AusAid) and Asia Sustainable and Alternative Energy Program (ASTAE).

Household Ventilation May Reduce Effects of Indoor Air Pollutants for Prevention of Lung Cancer

21 July 2014 15:00 (America/New_York)

Household Ventilation May Reduce Effects of Indoor Air Pollutants for Prevention of Lung Cancer: A Case-Control Study in a Chinese Population. PLoS One, July 2014.

Zi-Yi Jin, et al.

Background - Although the International Agency for Research on Cancer (IARC) has classified various indoor air pollutants as carcinogenic to humans, few studies evaluated the role of household ventilation in reducing the impact of indoor air pollutants on lung cancer risk. Objectives - To explore the association between household ventilation and lung cancer. Methods - A population-based case-control study was conducted in a Chinese population from 2003 to 2010. Epidemiologic and household ventilation data were collected using a standardized questionnaire. Unconditional logistic regression was employed to estimate adjusted odds ratios (ORadj) and their 95% confidence intervals (CI). Results - Among 1,424 lung cancer cases and 4,543 healthy controls, inverse associations were observed for good ventilation in the kitchen (ORadj = 0.86, 95% CI: 0.75, 0.98), bedroom (ORadj= 0.90, 95% CI: 0.79, 1.03), and both kitchen and bedroom (ORadj = 0.87, 95% CI: 0.75, 1.00). Stratified analyses showed lung cancer inversely associated with good ventilation among active smokers (ORadj = 0.85, 95% CI: 0.72, 1.00), secondhand smokers at home (ORadj = 0.77, 95% CI: 0.63, 0.94), and those exposed to high-temperature cooking oil fumes (ORadj = 0.82, 95% CI: 0.68, 0.99). Additive interactions were found between household ventilation and secondhand smoke at home as well as number of household pollutant sources. Conclusions - A protective association was observed between good ventilation of households and lung cancer, most likely through the reduction of exposure to indoor air pollutants, indicating ventilation may serve as one of the preventive measures for lung cancer, in addition to tobacco cessation.


Success of Alcohol Based Cooking Fuels for Reducing Household Air Pollution

21 July 2014 14:54 (America/New_York)

Success of Alcohol Based Cooking Fuels for Reducing Household Air Pollution. APHA Annual Meeting, Tuesday, November 18, 2014 : 10:50 AM – 11:10 AM.

Megan Graham, MPH , School of Public Health/Center for Healthy Development, Georgia State University, Atlanta, GA
Gulce Askin , Project Gaia Inc., Gettysburg, PA
Brady Luceno , Project Gaia Inc., Gettysburg, PA

Background. Over 3 billion people worldwide rely on biomass such as firewood, charcoal, or dung for their cooking needs. The use of biomass fuels emits high levels of carbon monoxide (CO) and particulate matter (PM) leading to pneumonia, acute lower respiratory infections, COPD, lung cancer, heart disease, and blindness. It is estimated that household air pollution (HAP) causes 3.5 million premature deaths annually. HAP is a top risk factors for ill-health globally and it is crucial to explore new cookstove and fuel interventions that reduce the burden of HAP and improve the health of women and children.

Research: This presentation explores the use of ethanol cooking fuel in Madagascar to reduce exposure to HAP and related illness. As part of a three year World Bank funded study, two communities in Madagascar (coastal and highland) were provided ethanol cookstoves. Following the intervention, ethanol cookstoves significantly reduced women’s exposure to CO in both regions (75% highland; 54% coastal) and children’s exposure by 60% in the highland location (non-significant reduction by 14% coastal). Households with ethanol stoves saw a significant reduction of headaches (93%) and eye irritation (72%) among women and a significant reduction in adult burns (74%) and child burns (64%). Modeling future uptake of ethanol stoves and pollutant reduction demonstrated a relative risk reduction for ALRIs among children, COPD among adults, and ischemic heart disease. The ethanol stove saved an average of 2.5 hours per day of cooking over traditional fuels. No other stove examined saw significant HAP reductions need to improve health.

Conclusion: Alcohol fuels and cookstoves have the potential to significantly reduce HAP and illness that may result from HAP exposure. Additional solutions other than solid fuel cookstoves are needed to make a significant health impact.


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