Indoor Air Quality Updates
If you have other suggestions for 2014 videos to add to the list please contact WASHplus.
Future of Cook stoves in India: Review and recommendations, 2014.
Authors: Moreshwar Hude, et al. TERRE Policy Centre, Pune
This paper, developed by an author and the guide who themselves were the users of various types of cooking stoves in their childhood and who have interacted with the present users, technology suppliers and decision makers, assesses the situation in respect of the cooking stoves, identifies the barriers-many of which are overlooked by zealous technocrats- and makes recommendation to overcome those barriers.
The Effect of Marketing Messages, Liquidity Constraints, and Household Bargaining on Willingness to Pay for a Nontraditional Cookstove
The Effect of Marketing Messages, Liquidity Constraints, and Household Bargaining on Willingness to Pay for a Nontraditional Cookstove, 2014.
Authors: Beltramo, Theresa, Impact Carbon; Levine, David I, UC Berkeley; Blalock, Garrick, Cornell University
Lack of product information, liquidity constraints, and women’s limited intrahousehold bargaining power can all slow adoption of new technologies that primarily benefit women and children in poor nations. One such technology, an improved cookstove, can replace inefficient traditional biomass cookstoves that cause significant environmental degradation and some four millions deaths a year. This experiment conducted in rural Uganda estimates willingness to pay for cookstove technologies using Vickrey second-price auctions. Using a randomized controlled trial we first test whether marketing messages which address specific information barriers increase willingness to pay.
Second, a within subjects comparison tests the effect of time payments on willingness to pay. To assess intrahousehold decision-making a correlational study examines the effect of being female, indicators of intra-household decision making, and earning a stable income on willingness to pay. Information campaigns have no large effect on willingness to pay. Neither marketing message- ‘the stove can improve health’ or ‘the stove can save time and money’-consistently increased willingness to pay. We find evidence that consumers in rural Uganda are liquidity constrained. Including time payments raised willingness to pay for a nontraditional cookstove by 41%. Each additional asset owned increased willingness to pay by 10%. Having a stable income increased willingness to pay by 8-10% for both men and women participants, though no effect on willingness to pay is observed of having a stable income for married women.
There is a large negative effect on willingness to pay if participant is female- on average men are willing to pay 21-23% more than women. Efforts to increase willingness to pay for nontraditional cookstoves which improve health and abate environmental harm may be more successful by designing and disseminating nontraditional cookstoves with features valued more highly by men and addressing liquidity constraints, instead of repeating marketing messages related to the cookstoves’ health and private economic benefits.
Clean cookstoves, windmills improve health while reducing emissions – study | Source/complete article: by Samuel Mintz and Laurie Goering, Reuters, Mar 11, 2014 |
LONDON (Thomson Reuters Foundation) – Clean cookstoves, power-generating windmills and reforestation projects deliver social benefits far beyond reductions in climate-changing carbon emissions, an internal study of projects certified by The Gold Standard has found.
In a look at 109 clean energy and forest projects around the world, all with emissions reductions measured and certified under the The Gold Standard label, economists found that cookstove projects produced $84 million a year in health benefits, in part by reducing exposure to coal, charcoal or firewood smoke, the Gold Standard Foundation said in a press release.
In addition, families participating in the projects saved $243 million annually on coal or firewood purchases, or the equivalent in time spent collecting firewood.
Windmill projects, similarly, saved countries that have installed them $100 million a year on fossil fuel imports, and created $12 million in salaries annually, the foundation said.
Altogether, the additional benefits beyond carbon emissions reductions, including ecosystem services and local employment, added up to more than a billion dollars over the life of the 109 projects, all of which are now completed, the study said.
Gold Standard certified carbon credits, launched in 2003 by the World Wildlife Fund and partners, are sold to individuals, companies and governments wanting to offset their own carbon emissions by paying to reduce emissions elsewhere.
The new look at environmental and social benefits from carbon reductions suggests that buyers of credits from everything from bio-digesters in China to water filters in Honduras are getting more for their money than reductions in climate-changing emissions.
“By being able to value critical outcomes, like improvements in health and employment, carbon credit buyers, funders and policy makers can better understand the big picture of what carbon finance can do when it’s implemented through the rigorous framework and auditing requirements of The Gold Standard,” said Adrian Rimmer, the CEO of The Gold Standard, in a press release.
The Gold Standard certifies nearly 1,000 projects around the world by a wide range of companies and organizations, including J.P. Morgan and a variety of non-profit organizations.
Twice as bad: new estimates for mortality from air pollution. Lancet Respiratory Medicine, April 2014.
Talha Khan Burki
WHO have upwardly revised their figures for the global mortality caused by air pollution. They estimate that about 7 million deaths occurred as a result of indoor and outdoor air pollution in 2012. The new figures take into account improvements in the methods and data collection used in previous years and honed techniques for measuring exposure-response.Indoor air pollution accounted for 4·3 million deaths in 2012, largely in the South-East Asia and Western Pacific regions. Respiratory illness made up 40% of the death toll. It all comes down to smoke inhalation, either from open fires or inefficient cook stoves. Children younger than 5 years are particularly vulnerable: 2012 saw over 500 000 deaths from acute lower respiratory infections related to indoor air pollution in this age bracket.
Outdoor air pollution accounted for 3·7 million deaths in 2012, concentrated in low-income and middle-income countries; 389 000 of these deaths were from chronic obstructive respiratory disease, and 227 000 from lung cancer (emissions from diesel engines are particularly culpable in this). Since communities are exposed to several types of pollution, WHO estimated the total number of pollution-related deaths at 7 million (rather than 8 million).Tackling outdoor pollution requires a wide ranging approach. “We would like to have more interventions on healthy urban planning”, affirmed WHO’s Maria Neira. She notes that the transport sector has provided much evidence on environmentally friendly and sustainable systems. Clearly, industry has a large part to play, and there are plenty of proven interventions, such as fitting flue-gas desulphurisation systems to coal-burning power plants, that can help ameliorate matters.
Later this year, WHO will launch its guidelines on indoor air quality. About 3 billion people live in households that rely on solid fuel for cooking and heating. “They burn what is available”, explains Jon Ayres from Birmingham University. Rolling out an efficient means of combusting this fuel, as envisaged by the UN Foundation’s Global Alliance for Clean Cook Stoves, is crucial. But simply ensuring a supply of such stoves will not suffice—when they break down, users tend to return to their previous habits. Ayres emphasises the importance of co-opting local entrepreneurs to produce inexpensive, good-quality stoves and subsequently provide maintenance services. “It’s a big job—we have to enable great swathes of people to become the users, producers, and maintainers of these better stoves”, he told The Lancet Respiratory Medicine.For more on the WHO report see http://www.who.int/phe/health_topics/outdoorair/databases/FINAL_HAP_AAP_BoD_24March2014.pdf?ua=1
Current debates and future research needs in the clean cookstove sector. Energy for Sustainable Development, Volume 20, June 2014, Pages 49–57.
Authors: Gregory L. Simona, et al.
• Despite considerable growth in the clean cookstove sector, many debates remain.
• Vetting of stove performance and appeal prior to scale-up is needed in sector.
• Given corollary benefits, local production of effective stoves should be encouraged.
• There is a need to analyze the suitability of diverse subsidies in various settings.
• Decline in carbon credit prices has increased the need to diversify investment types.
The international clean cookstove sector has undergone considerable growth over the past decade. We use this critical juncture – where program priorities and strategies are formalized and converted into institutional norms and practices – to review current debates and areas for future research. We focus our review on four important areas and suggest industry participants expand and refine efforts to (i) balance technical stove performance with implementation needs and stove user compatibility; (ii) understand the trade-offs associated with local and imported production methods; (iii) determine a suitable role for direct subsidies for purchasing stoves and indirect subsidies for research, institutional development and distribution of stoves; and (iv) develop an appropriate finance strategy to support dissemination amidst carbon market uncertainties. Given the complex and interdisciplinary nature of the clean cookstove sector, we hope our appraisal of these four issues will inform innovation and invite new insights.
Comment: Climate change and health: on the latest IPCC report. Lancet, April 2014.
Authors: Alistair Woodward, et al.
The health co-beneﬁ ts of action on climate change could be very large. For instance, a reduction of emissions of methane and black carbon might directly prevent 2·0–2·5 million deaths per year worldwide, according to one estimate. When converted into economic terms, the health gains could oﬀ set much of the early cost for mitigation of climate change.
A cross-sectional study of determinants of indoor environmental exposures in households with and without chronic exposure to biomass fuel smoke
A cross-sectional study of determinants of indoor environmental exposures in households with and without chronic exposure to biomass fuel smoke. Env Health, March 2014.
Authors: Suzanne L Pollard, et al.
Background – Burning biomass fuels indoors for cooking is associated with high concentrations of particulate matter (PM) and carbon monoxide (CO). More efficient biomass-burning stoves and chimneys for ventilation have been proposed as solutions to reduce indoor pollution. We sought to quantify indoor PM and CO exposures in urban and rural households and determine factors associated with higher exposures. A secondary objective was to identify chronic vs. acute changes in cardiopulmonary biomarkers associated with exposure to biomass smoke.
Methods – We conducted a census survey followed by a cross-sectional study of indoor environmental exposures and cardiopulmonary biomarkers in the main household cook in Puno, Peru. We measured 24-hour indoor PM and CO concentrations in 86 households. We also measured PM2.5 and PM10 concentrations gravimetrically for 24 hours in urban households and during cook times in rural households, and generated a calibration equation using PM2.5 measurements.
Results – In a census of 4903 households, 93% vs. 16% of rural vs. urban households used an open-fire stove; 22% of rural households had a homemade chimney; and <3% of rural households participated in a national program encouraging installation of a chimney. Median 24-hour indoor PM2.5 and CO concentrations were 130 vs. 22 µg/m3 and 5.8 vs. 0.4 ppm (all p<0.001) in rural vs. urban households. Having a chimney did not significantly reduce median concentrations in 24-hour indoor PM2.5 (119 vs. 137 µg/m3; p=0.40) or CO (4.6 vs. 7.2 ppm; p=0.23) among rural households with and without chimneys. Having a chimney did not significantly reduce median cook-time PM2.5 (360 vs. 298 µg/m3, p=0.45) or cook-time CO concentrations (15.2 vs. 9.4 ppm, p=0.23). Having a thatched roof (p=0.007) and hours spent cooking (p=0.02) were associated with higher 24-hour average PM concentrations. Rural participants had higher median exhaled CO (10 vs. 6 ppm; p=0.01) and exhaled carboxyhemoglobin (1.6% vs. 1.0%; p=0.04) than urban participants.
Conclusions Indoor air concentrations associated with biomass smoke were six-fold greater in rural vs. urban households. Having a homemade chimney did not reduce environmental exposures significantly. Measures of exhaled CO provide useful cardiopulmonary biomarkers for chronic exposure to biomass smoke.
An Integrated Risk Function for Estimating the Global Burden of Disease Attributable to Ambient Fine Particulate Matter Exposure
An Integrated Risk Function for Estimating the Global Burden of Disease Attributable to Ambient Fine Particulate Matter Exposure. Environmental Health Perspectives, Feb 2014.
Authors: Richard T. Burnett, et al.
Background: Estimating the burden of disease attributable to long-term exposure to fine particulate matter (PM2.5) in ambient air requires knowledge of both the shape and magnitude of the relative risk function (RR). However, there is inadequate direct evidence to identify the shape of the mortality RR functions at high ambient concentrations observed in many places in the world.
Objective: Develop relative risk (RR) functions over entire global exposure range for causes of mortality in adults: ischemic heart disease (IHD), cerebrovascular disease (stroke), chronic obstructive pulmonary disease (COPD), and lung cancer (LC). In addition, develop RR functions for the incidence of acute lower respiratory infection (ALRI) that can be used to estimate mortality and lost-years of healthy life in children less than 5 years old.
Methods: An Integrated Exposure-Response (IER) model was fit by integrating available RR information from studies of ambient air pollution (AAP), second hand tobacco smoke (SHS), household solid cooking fuel (HAP) and active smoking (AS). AS exposures were converted to estimated annual PM2.5 exposure equivalents using inhaled doses of particle mass. Population attributable fractions (PAF) were derived for every country based on estimated world-wide ambient PM2.5 concentrations.
Results: The IER model was a superior predictor of RR compared to seven other forms previously used in burden assessments. The PAF (%) attributable to AAP exposure varied among countries from: 2-41 for IHD, 1-43 for stroke, < 1-21 for COPD, < 1-25 for LC, and < 1-38 for ALRI.
Conclusions: We developed a fine particulate mass-based RR model that covered the global range of exposure by integrating RR information from different combustion types that generate emissions of particulate matter. The model can be updated as new RR information becomes available.
Impact of neighborhood biomass cooking patterns on episodic high indoor particulate matter concentrations in clean fuel homes in Dhaka, Bangladesh
Impact of neighborhood biomass cooking patterns on episodic high indoor particulate matter concentrations in clean fuel homes in Dhaka, Bangladesh. Indoor Air, April 2014.
Authors: H. Salje et al.
Exposure to particulate matter (PM2.5) from the burning of biomass is associated with increased risk of respiratory disease. In Dhaka, Bangladesh, households that do not burn biomass often still experience high concentrations of PM2.5, but the sources remain unexplained. We characterized the diurnal variation in the concentrations of PM2.5 in 257 households and compared the risk of experiencing high PM2.5 concentrations in biomass and non-biomass users. Indoor PM2.5 concentrations were estimated every minute over 24 h once a month from April 2009 through April 2010.
We found that households that used gas or electricity experienced PM2.5 concentrations exceeding 1000 μg/m3 for a mean of 35 min within a 24-h period compared with 66 min in biomass-burning households. In both households that used biomass and those that had no obvious source of particulate matter, the probability of PM2.5 exceeding 1000 μg/m3 were highest during distinct morning, afternoon, and evening periods. In such densely populated settings, indoor pollution in clean fuel households may be determined by biomass used by neighbors, with the highest risk of exposure occurring during cooking periods. Community interventions to reduce biomass use may reduce exposure to high concentrations of PM2.5 in both biomass and non-biomass using households.
Emissions and Climate-Relevant Optical Properties of Pollutants Emitted from a Three-Stone Fire and the Berkeley-Darfur Stove Tested under Laboratory Conditions
Emissions and Climate-Relevant Optical Properties of Pollutants Emitted from a Three-Stone Fire and the Berkeley-Darfur Stove Tested under Laboratory Conditions. Environ Sci Technol. 2014 Mar 31.
Authors: Preble CV, Hadley OL, Gadgil A, Kirchstetter T.
Abstract – Cooking in the developing world generates pollutants that endanger the health of billions of people and contribute to climate change. This study quantified pollutants emitted when cooking with a three-stone fire (TSF) and the Berkeley-Darfur Stove (BDS), the latter of which encloses the fire to increase fuel efficiency. The stoves were operated at the Lawrence Berkeley National Laboratory testing facility with a narrow range of fuel feed rates to minimize performance variability. Fast (1 Hz) measurements of pollutants enabled discrimination between the stoves’ emission profiles and development of woodsmoke-specific calibrations for the aethalometer (black carbon, BC) and DustTrak (fine particles, PM2.5). The BDS used 65 ± 5% (average ± 95% confidence interval) of the wood consumed by the TSF and emitted 50 ± 5% of the carbon monoxide emitted by the TSF for an equivalent cooking task, indicating its higher thermal efficiency and a modest improvement in combustion efficiency. The BDS reduced total PM2.5 by 50% but achieved only a 30% reduction in BC emissions.
The BDS-emitted particles were, therefore, more sunlight-absorbing: the average single scattering albedo at 532 nm was 0.36 for the BDS and 0.47 for the TSF. Mass emissions of PM2.5 and BC varied more than emissions of CO and wood consumption over all tests, and emissions and wood consumption varied more among TSF than BDS tests. The international community and the Global Alliance for Clean Cookstoves have proposed performance targets for the highest tier of cookstoves that correspond to greater reductions in fuel consumption and PM2.5 emissions of approximately 65% and 95%, respectively, compared to baseline cooking with the TSF. Given the larger decrease in BC than carbon dioxide (CO2) emissions for stoves that achieve this stretch goal and BC’s extremely high global warming potential, the short term climate change mitigation from avoided BC emissions could exceed that from avoided CO2 emissions.
Socio-Economic Survey as a Support Tool during the Scaling Up of Improved Stoves in the Logone Valley
Socio-Economic Survey as a Support Tool during the Scaling Up of Improved Stoves in the Logone Valley (Chad/Cameroon). Sustainability 2014, 6(3), 1427-1447; doi:10.3390/su6031427
Authors: Francesco Vitali and Mentore Vaccariemail
Abstract: Field assessment plays a key role in the evaluation of the energy access modalities and of the socio-economic features that may influence the beneficiaries’ choices and preferences in the adoption and use of an energy technology. This work presents the findings of a survey conducted during the implementation of a cooperation project in the Logone Valley (Chad/Cameroon). After an initial period of promotion of an improved cookstove (ICS), a survey was conducted that was aimed at identifying different beneficiary groups, matching their preferences and cooking habits to the technology proposed, in order to best tailor the scaling-up strategy.
In-depth analysis of the data gathered identified two household-user behaviors and the relative influencing features: in the urban area, the increased adoption rates confirmed the appropriateness of the technology proposed and its sustainability, whereas in the rural area, ICS use was not perceived by the final users as advantageous and lower adoption rates were observed. Thus, due to the outcome of the survey, the project action was re-oriented in order to achieve a higher impact on the territory and on the population.
Issue 139 | March 28, 2014 | Global Burden of Disease from Household Air Pollution
In new estimates released on March 25, the World Health Organization reports that in 2012 around 7 million people died—one in eight of total global deaths—as a result of air pollution exposure. This finding more than doubles previous estimates and confirms that air pollution is now the world’s largest single environmental health risk. Resources in this issue of the WASHplus Weekly include links to fact sheets, research, and reports related to the burden of disease from household air pollution (HAP).
We also invite you to join the Clean Cookstove Community on Linkedin which we hope will become a crowdsourcing community for sharing information and collaborating on household air pollution issues.
7 million Premature Deaths Annually Linked to Air Pollution, 2014. World Health Organization (WHO). (Link)
The WHO estimates that the joint effects of HAP and ambient air pollution were attributable to over 7 million deaths in 2012, representing one of eight total global deaths and confirming that air pollution is now the world’s largest single environmental health risk. The WHO also estimates that the South Asian and Southeast Asian and Western Pacific regions bear most of the burden with 1.69 and 1.62 million deaths, respectively. Almost 600,000 deaths occur in Africa, 200,000 in the Eastern Mediterranean region, 99,000 in Europe, and 81,000 in the Americas. The remaining 19,000 deaths occur in high income countries.
Senator Collins Introduces Clean Cookstoves Bill That Would Improve Environment, Public Health, March 10, 2014. (Link)
The “Clean Cookstoves Support Act,” co-sponsored by Senator Dick Durbin (D-IL), would reinforce the U.S. Government’s commitment to spur the adoption of clean cookstoves around the world. It would require the Secretary of State to work to advance the goals of the Global Alliance for Clean Cookstoves, which was formed through the leadership of Secretary of State Hillary Clinton and the United Nation’s Foundation to help create a thriving global market for clean and efficient household cooking solutions.
FACT SHEETS/BRIEFING NOTES
Household Air Pollution and Health. Fact Sheet, 2014. World Health Organization.(Link)
An update of WHO’s estimates on the health impacts of household air pollution as well as its impact on health equity, development, and climate change. The document also includes an overview of WHO’s response and how it connects to Millennium Development Goal targets.
Air Pollution Estimates: Burden of Disease from Household Air Pollution for 2012, Summary of Results. World Health Organization, March 2014. (Link)
A regional and demographic statistical breakdown of the health impacts of household air pollution.
The Burden of Disease from Household Air Pollution: How and Why Are the Estimates Changing? 2014. Global Alliance for Clean Cookstoves. (Link)
WHO just released its 2012 estimates of the global burden of disease from air pollution and reports that globally 4.3 million deaths were attributable to household air pollution in 2012, almost all in low and middle income countries. The new estimates make it clear that reducing air pollution could save millions of lives and further underscore the need for clean cooking technologies for the close to 3 billion people who continue to live in homes using solid fuels for cooking and heating.
Millions Dead: How Do We Know and What Does It Mean? Methods Used in the Comparative Risk Assessment of Household Air Pollution. Annual Review of Public Health, March 2014. K Smith. (Link with supplements)
In the comparative risk assessment (CRA) done as part of the Global Burden of Disease project (GBD-2010), the global and regional burdens of HAP due to the use of solid cook fuels were estimated along with more than 60 other risk factors. This article describes how the HAP CRA was framed; how global HAP exposures were modeled; how diseases were judged to have sufficient evidence for inclusion; and how meta-analyses and exposure-response modeling were done to estimate relative risks.
The Effect of Biomass Fuel Exposure on the Prevalence of Asthma in Adults in India: Review of Current Evidence. Journal of Asthma, Mar 2014. J Trevor. (Abstract/order info)
This review examines the current literature linking biomass smoke exposure to the reporting of asthma symptoms. The reviewed articles showed an increased odds ratio for reporting a diagnosis of asthma or symptoms consistent with asthma following biomass smoke exposure.
Switching to Biogas: What Effect Could It Have on Indoor Air Quality and Human Health? Biomass and Bioenergy, Mar 2014. S Semple. (Abstract/order info)
Small household biogas digesters are now available and are likely to have the capacity to significantly reduce household concentrations of respirable particulate matter and carbon monoxide. Although no direct evidence is available, comparison with households using liquified petroleum gas suggest that improvements in indoor air quality may be of the order of 66 percent to 99 percent.
Effects of Woodsmoke Exposure on Airway Inflammation in Rural Guatemalan Women. PLoS One, Mar 2014. M Guarnieri. (Link)
The objective of this work was to assess whether lower woodsmoke exposure from use of a stove with a chimney, compared to open fires, is associated with lower markers of airway inflammation in young women.
Biomass Fuel Use and the Exposure of Children to Particulate Air Pollution in Southern Nepal. Environment International, Mar 2014. D. Devakumara. (Abstract/order info)
The exposure of children to air pollution in low resource settings is believed to be high because of the common use of biomass fuels for cooking. We used microenvironment sampling to estimate the respirable fraction of air pollution to which 7 to 9 year-old children in southern Nepal were exposed. The exposure of children to air pollution in rural households was much higher than particulate exposure recommendations from WHO and the National Ambient Air Quality Standards for Nepal.
Solid Fuel Use is a Major Risk Factor for Acute Coronary Syndromes Among Rural Women: A Matched Case Control Study. Public Health, Jan 2014. Z. Fatami, et al. (Link)
Almost half of the world’s population uses solid fuel for cooking, exposing women to high levels of particulate pollution in indoor air. The risk of acute coronary syndrome (ACS) was assessed among rural women, according to their use of solid fuel. Current use of solid fuel was strongly associated with ACS and risk was lowest in women who had last used solid fuel more than 15 years earlier.
Adherence to Reduced-Polluting Biomass Fuel Stoves Improves Respiratory and Sleep Symptoms in Children. BMC Pediatrics, 14:12, 2014. R Accinelli. (Link)
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. Improvements in respiratory and sleep-related symptoms associated with elevated indoor biomass pollution occur only following implementation and exclusive utilization of improved kitchen stoves.
An Integrated Risk Function for Estimating the Global Burden of Disease Attributable to Ambient Fine Particulate Matter Exposure. Environmental Health Perspectives, Feb 2014. R Burnett. (Link)
The objective of this research was to develop relative risk functions over the entire global exposure range for causes of mortality in adults: ischemic heart disease, cerebrovascular disease (stroke), chronic obstructive pulmonary disease, and lung cancer.
WASHplus Weeklies will highlight topics such as Urban WASH, Indoor Air Pollution, Innovation, Household Water Treatment and Storage, Hand Washing, Integration, and more. If you would like to feature your organization’s materials in upcoming issues, please send them to Dan Campbell, WASHplus Knowledge Resources Specialist, firstname.lastname@example.org.
Fact Sheet: Household Air Pollution and Health: March 2014. World Health Organization.
- Around 3 billion people cook and heat their homes using open fires and simple stoves burning biomass (wood, animal dung and crop waste) and coal.
- Over 4 million people die prematurely from illness attributable to the household air pollution from cooking with solid fuels.
- More than 50% of premature deaths among children under 5 are due to pneumonia caused by particulate matter (soot) inhaled from household air pollution.
- 3.8 million premature deaths annually from noncommunicable diseases including stroke, ischaemic heart disease, chronic obstructive pulmonary disease (COPD) and lung cancer are attributed to exposure to household air pollution.
Indoor air pollution and household energy: the forgotten 3 billion
Around 3 billion people still cook and heat their homes using solid fuels (i.e. wood, crop wastes, charcoal, coal and dung) in open fires and leaky stoves. Most are poor, and live in low- and middle-income countries.
Such inefficient cooking fuels and technologies produce high levels of household air pollution with a range of health-damaging pollutants, including small soot particles that penetrate deep into the lungs. In poorly ventilated dwellings, indoor smoke can be 100 times higher than acceptable levels for small particles. Exposure is particularly high among women and young children, who spend the most time near the domestic hearth.
Impacts on health
4.3 million people a year die prematurely from illness attributable to the household air pollution caused by the inefficient use of solid fuels (2012 data). Among these deaths:
- 12% are due to pneumonia
- 34% from stroke
- 26% from ischaemic heart disease
- 22% from chronic obstructive pulmonary disease (COPD), and
- 6% from lung cancer.
Pneumonia – Exposure to household air pollution almost doubles the risk for childhood pneumonia. Over half of deaths among children less than 5 years old from acute lower respiratory infections (ALRI) are due to particulate matter inhaled from indoor air pollution from household solid fuels (WHO, 2014).
Stroke - Nearly one quarter of all premature deaths due to stroke (i.e. about 1.4 million deaths of which half are in women) can be attributed to the chronic exposure to household air pollution caused by cooking with solid fuels.
Ischaemic heart disease - Approximately 15% of all deaths due to ischaemic heart disease, accounting for over a million premature deaths annually, can be attributed to exposure to household air pollution.
Chronic obstructive pulmonary disease - Over one third of premature deaths from chronic obstructive pulmonary disease (COPD) in adults in low- and middle-income countries are due to exposure to household air pollution. Women exposed to high levels of indoor smoke are 2.3 times as likely to suffer from COPD than women who use cleaner fuels. Among men (who already have a heightened risk of COPD due to their higher rates of smoking), exposure to indoor smoke nearly doubles (i.e. 1.9) that risk.
Lung cancer - Approximately 17% of annual premature lung cancer deaths in adults are attributable to exposure to carcinogens from household air pollution caused by cooking with solid fuels like wood, charcoal or coal. The risk for women is higher, due to their role in food preparation.
Other health impacts and risks
More generally, small particulate matter and other pollutants in indoor smoke inflame the airways and lungs, impairing immune response and reducing the oxygen-carrying capacity of the blood.
There is also evidence of links between household air pollution and low birth weight, tuberculosis, cataract, nasopharyngeal and laryngeal cancers.
Mortality from ischaemic heart disease and stroke are also affected by risk factors such as high blood pressure, unhealthy diet, lack of physical activity and smoking. Some other risks for childhood pneumonia include suboptimal breastfeeding, underweight and second-hand smoke. For lung cancer and chronic obstructive pulmonary disease, active smoking and second-hand tobacco smoke are also main risk factors.
Impacts on health equity, development and climate change
Without a substantial change in policy, the total number of people relying on solid fuels will remain largely unchanged by 2030 (World Bank, 2010). The use of polluting fuels also poses a major burden on sustainable development.
- Fuel gathering consumes considerable time for women and children, limiting other productive activities (e.g. income generation) and taking children away from school. In less secure environments, women and children are at risk of injury and violence during fuel gathering.
- Black carbon (sooty particles) and methane emitted by inefficient stove combustion are powerful climate change pollutants.
- The lack of access to electricity for at least 1.2 billion people (many of whom then use kerosene lamps for lighting) creates other health risks, e.g. burns, injuries and poisonings from fuel ingestion, as well as constraining other opportunities for health and development, e.g. studying or engaging in small crafts and trades, which require adequate lighting.
Our new paper in the Annual Review of Public Health has an immense amount of additional information on how the comparative risk assessment for household air pollution from solid cookfuels (HAP) was done. Indeed,covering over 60 risk factors, the original Lim et al. Lancet article (Dec 2012) had less than 300 words on HAP itself, while ours has more than 30,000 words (with the supplement). >100x more. Of course, we do not attempt to produce the vast array of figures and tables comparing with other risk factors and by age, sex, region, etc.
We found some relatively minor glitches in how the calculations were done during the last hectic weeks before the Lancet article went to press and believe that the ARPH article is a more accurate representation of the estimates that can still be compared across the other risk factors. Unlike the Lancet article, it also incorporates the burden from HAP’s contribution to outdoor air pollution, corrected for overlap as explained. The resulting premature death total is 3.9 million globally for 2010, quite close to the 3.5 directly from HAP plus the implied 0.5 million due to an uncorrected addition of HAP’s contribution to outdoor pollution in the Lancet article.
We also of course could take direct advantage of the publication of some major pieces of the HAP analysis that occurred after the Lancet article.
We also are able to do some sensitivity analysis toward the end of our article that show, for example, that the results are not sensitive to uncertainties in the exposure assessment, but that the ranking of HAP against other risk factors in the poorest countries is quite sensitive to the choice of what risk factors were left out in the main GBD study.
The paper and supplement can be downloaded from my website below can the original Lancet article. Please note that Nigel Bruce and I are co-first authors/k
Millions Dead: How Do We Know and What Does It Mean? Methods Used in the Comparative Risk Assessment of Household Air Pollution
Kirk R. Smith,1,. Nigel Bruce,2,. Kalpana Balakrishnan,3 Heather Adair-Rohani,1 John Balmes,1,4 ZoNe Chafe,1,5 Mukesh Dherani,2 H. Dean Hosgood,6 Sumi Mehta,7 Daniel Pope,2 Eva Rehfuess,8 and others in the HAP CRA Expert Group
Abstract – In the Comparative Risk Assessment (CRA) done as part of the Global Burden of Disease project (GBD-2010), the global and regional burdens of household air pollution (HAP) due to the use of solid cookfuels, were estimated along with 60+ other risk factors. This article describes how the HAP CRA was framed; how global HAP exposures were modeled; how diseases were judged to have sufficient evidence for inclusion; and how meta-analyses and exposure-response modeling were done to estimate relative risks. We explore relationships with the other air pollution risk factors: ambient air pollution, smoking, and secondhand smoke. We conclude with sensitivity analyses to illustrate some of the major uncertainties and recommendations for future work. We estimate that in 2010 HAP was responsible for 3.9 million premature deaths and ~4.8% of lost healthy life years (DALYs), ranking it highest among environmental risk factors examined and one of the major risk factors of any type globally.
Kirk R. Smith, MPH, PhD
(Professor of Global Environmental Health, University of California, Berkeley)
Fulbright-Nehru Distinguished Chair (Fall/Winter 2013/14)
Centre for Atmospheric Sciences
Indian Institute of Technology-Delhi
Delhi cell: (91) 96-5092-6030 [note new number]
USAID – Cooking With Green Charcoal Helps to Reduce Deforestation in Haiti | Source/complete article: by Anna-Maija Mattila Litvak, USAID Impact Blog, March 13th 2014 |
Excerpts – An organization in northern Haiti is promoting a cooking fuel made from agricultural waste that can save trees, help farmers increase their yields and generate additional income.
“Our aim is to try to stop deforestation in Haiti by teaching people to switch from cooking with charcoal to using cooking briquettes, small discs made from charred agricultural waste,” said Anderson Pierre, the Supply Chain Manager forCarbon Roots International (CRI), a USAID-supported non-profit organization operating in Quartier Morin.
Despite the fact that only about 2 percent of Haiti’s forests remain, it is difficult to shift habits of cooking with wood charcoal to methods that are environmentally friendly. According to Pierre, other alternative fuels are still not well-known – or accepted.
“We work little by little, changing perceptions and providing information on the benefits of using briquettes,” Pierre said.
CRI employs smallholder farmers and entrepreneurs to produce carbon-rich char from agricultural waste such as sugarcane bagasse, the fibrous matter that remains after sugarcane stalks are crushed to extract their juice. CRI uses this waste to create two innovative products: renewable charcoal cooking briquettes called “green charcoal,” and “biochar,” a potent natural soil additive that increases soil fertility and removes carbon from the atmosphere. CRI sells the briquettes as an alternative to traditional wood charcoal through a network of women retailers, and disburses biochar back to farmers to increase crop yields and further raise incomes.
As a result, the project contributes to the sustainability of Haitian agriculture and provides income opportunities for women entrepreneurs. It offers a comparably priced, locally appropriate green cooking fuel to the Haitian marketplace, as well as encourages the adoption of biochar as a viable tool for increasing agricultural productivity and soil resiliency.
CRI’s efforts to promote green charcoal are gradually gaining ground in northern Haiti. While they’ve been focusing on market research and production, they plan to expand to bulk sales and more roadside kiosks this spring. In December, CRI ran a public awareness campaign in Quartier Morin under the slogan “Green Charcoal is Your Charcoal”, using demonstration stands and offering free samples of briquettes.
USAID is supporting CRI through a $100,000 Development Innovation Ventures award. The USAID award has helped CRI prove itself — it developed a network of producers, started production and created viable markets for biomass products.
- Source/complete article: by Anna-Maija Mattila Litvak, USAID Impact Blog, March 13th 2014 |
Commentary: Switching to biogas – What effect could it have on indoor air quality and human health?
Authors: Sean Semple, Andrew Apsley, Adamu Wushishi, Jo Smith
• Indoor air pollution from biomass fuels causes a health burden comparable to malaria.
• Data on improvements to household air quality from switching to biogas are lacking.
• Using comparable studies for LPG, reductions in PM2.5 and CO may be as much as 90%.
• Health benefits of such exposure reductions are likely to be considerable.
• Longitudinal biogas intervention studies need to assess exposure and health changes.
Indoor combustion of solid biomass fuels such as wood and charcoal is common in large parts of the world and has been demonstrated to lead to high levels of exposure to fine particulate matter and gases such as carbon monoxide. Such exposures have been shown to be linked to increased risk of respiratory and cardiovascular illness and may contribute to as many as 2 million early deaths globally per annum. There are a range of interventions currently being trialled including improved cookstoves and changes in fuel type. Small household biogas digesters are now available and are likely to have the capacity to significantly reduce household concentrations of respirable particulate matter and carbon monoxide. Although no direct evidence is available, comparison with households using Liquified Petroleum Gas (LPG) would suggest that improvements in indoor air quality may be of the order of 66–99%. Such improvements in households taking up this technology could bring respiratory and cardiovascular health benefits of the order of 20–25% reduction in risk of a wide range of diseases. There is a need for well-designed longitudinal studies to examine the impact of introducing biogas digesters to communities on both exposure to indoor air pollution and the health effects this may bring.
Effects of Woodsmoke Exposure on Airway Inflammation in Rural Guatemalan Women. PLoS One, Mar 2014.
Authors: Michael J. Guarnieri, et al.
Background – More than two-fifths of the world’s population uses solid fuels, mostly biomass, for cooking. The resulting biomass smoke exposure is a major cause of chronic obstructive pulmonary disease (COPD) among women in developing countries.
Objective – To assess whether lower woodsmoke exposure from use of a stove with a chimney, compared to open fires, is associated with lower markers of airway inflammation in young women.
Design – We carried out a cross-sectional analysis on a sub-cohort of participants enrolled in a randomized controlled trial in rural Guatemala, RESPIRE.
Participants – We recruited 45 indigenous women at the end of the 18-month trial; 19 women who had been using the chimney stove for 18–24 months and 26 women still using open fires.
Measurements – We obtained spirometry and induced sputum for cell counts, gene expression of IL-8, TNF-α, MMP-9 and 12, and protein concentrations of IL-8, myeloperoxidase and fibronectin. Exhaled carbon monoxide (CO) and 48-hr personal CO tubes were measured to assess smoke exposure.
Results – MMP-9 gene expression was significantly lower in women using chimney stoves. Higher exhaled CO concentrations were significantly associated with higher gene expression of IL-8, TNF-α, and MMP-9. Higher 48-hr personal CO concentrations were associated with higher gene expression of IL-8, TNF- α, MMP-9 and MMP-12; reaching statistical significance for MMP-9 and MMP-12.
Conclusions – Compared to using an open wood fire for cooking, use of a chimney stove was associated with lower gene expression of MMP-9, a potential mediator of airway remodeling. Among all participants, indoor biomass smoke exposure was associated with higher gene expression of multiple mediators of airway inflammation and remodeling; these mechanisms may explain some of the observed association between prolonged biomass smoke exposure and COPD.
March 10, 2014 – Sen. Collins Introduces Clean Cookstoves Bill That Would Improve Environment, Public Health
Excerpt: WASHINGTON, D.C. – U.S. Senator Susan Collins today introduced the “Clean Cookstoves Support Act,” a bill that would reduce carbon pollution and improve public health by supporting a global market for clean and efficient cookstoves.
“Replacing unsafe cookstoves with modern alternatives is the ‘low-hanging fruit’ of environmental fixes,” Senator Collins said. “It can be done relatively quickly and inexpensively and would improve lives, empower women, and combat pollution around the world.”
Nearly half the world’s population cooks over open fires or inefficient, polluting and unsafe cookstoves using wood, agricultural waste, dung, coal, and other solid fuels. Smoke from these traditional stoves is associated with chronic and acute diseases that disproportionately affect women and young children. These stoves also create serious environmental problems by emitting black carbon that contributes to regional air pollution and climate change.
The “Clean Cookstoves Support Act,” co-sponsored by Senator Dick Durbin (D-IL), would reinforce the U.S. Government’s commitment to spur the adoption of clean cookstoves around the world. It would require the Secretary of State to work to advance the goals of the Global Alliance for Clean Cookstoves, which was formed through the leadership of Secretary of State Clinton and the United Nation’s Foundation to help create a thriving global market for clean and efficient household cooking solutions. The Alliance has the goal of spurring the adoption of clean cookstoves in 100 million homes by 2020.
The bill would also authorize existing funding commitments made by the U.S. Government to support the Alliance’s mission. Several federal agencies and departments-including the Departments of State, Energy, Health and Human Services and the United States Agency for International Development, the Environmental Protection Agency, the National Science Foundation and the Overseas Private Investment Corporation-have committed a total of up to $125 million to the sector for the first five years of the Alliance.
Field Study of Black Carbon Reductions From Use of Improved Cookstoves, 2014.
Black carbon (BC) is a component of fine particulate matter that is generated during incomplete combustion of fossil and biomass fuels. BC is thought to contribute to human lung disease and premature mortality, is a short-lived climate forcing agent, and the second largest contributor to global warming after carbon dioxide. Because residential uses of biomass fuel (for cooking, heating, and lighting) contribute significantly to regional production of BC, targeting cooking for reduction in emissions has been identified as one of the top 14 measures out of 400 for near-term mitigation of climate change (Shindell et al., 2012). Similarly, of all measures to reduce BC, targeting residential sources could have the greatest overall health benefits (Anenberg et al., 2013). These directives may especially hold true in India, where residential biofuel use is the biggest individual source, contributing close to 50% of all BC emissions (Streets et al., 2013).
Thus, usage of improved biomass cookstoves that can substantially reduce BC in households may result in significant health and climate benefits. In a series of controlled cooking tests in one household, Project Surya identified that “forced draft” stoves were the most effective technologies, of those tested, for reducing black carbon concentrations. While this data is encouraging, more data is needed to quantify the reductions in BC concentrations when a household uses a forced-draft cookstove for daily cooking. The current lack of data under real-world conditions is due to multiple factors, including challenges in capturing BC emissions in the field and the cost of data collection using industry standard instruments.