Following the publication of a study that showed one type of biomass cookstove given away to users in Malawi reduced burns by 40% but had little impact on reported rates of child pneumonia, the Alliance issued the following statement:
“Daily exposure to toxic smoke from traditional cooking practices is one of the world’s biggest – but least well-known killers. The World Health Organization estimates that exposure to smoke from the simple act of cooking causes more than four million premature deaths per year - millions more fall sick, and thousands of people suffer severe burns and injuries. Beyond the dramatic health impacts, this way of cooking causes widespread damage to the environment, women’s empowerment, climate, and the economy.
“Based on the type of stove evaluated in the Malawi trial, the lack of impact on child pneumonia is not surprising. While this stove may offer a range of environmental, climate, and lifestyle benefits, the stove does not meet WHO indoor air quality guideline levels expected to reduce child pneumonia under the best performing laboratory conditions.
This point is critical.
Lancet has already published a response to the study from household energy experts Dr. Majid Ezzati and Dr. Jill Baumgartner outlining the limitations of the study, specifically the use of an intervention stove that predictably would not reduce emissions to the levels recommended by the WHO. We know that the potential for clean cooking to provide public health benefits in the real world depends on the quality of the cookstove, the type and condition of the fuel burned, the rate of stove and fuel adoption - whether the stoves are used properly, consistently and exclusively by the consumers who have purchased them.
The paper’s authors state that only half of participating households report using the intervention stoves for all of their cooking needs after two years. Stove use data, however, indicates that by the end of the study those households only use their intervention stoves for 0.34 cooking events per day, on average. With stove use rates ranging from minimal to up to half of the households using the stoves exclusively (as suggested by self-reported data), we would not expect to see health benefits among participants.
Health benefits are also not just dependent on whether clean stoves and fuels are used in each household (levels of indoor air pollution) but whether they are used at scale in the larger community. Smoke from cooking has been shown to have a large effect on individual health and wellbeing and other combustion-related sources of pollution, including tobacco, vehicles, and trash burning need to be addressed as well in order to achieve clean air. As with other environmental health risk factors like malaria, water and sanitation, we will need to achieve widespread coverage with the best possible interventions and address other major sources of exposure in order to maximize health benefits.
The Malawi study found a significant reduction in reports of burns from participants. This is big news. Burns from open fires and unsafe cookstoves are an insidious risk faced by poor households, contributing to a substantial percentage of the estimated 195,000 burn deaths that occur annually. The study provides clear evidence of how use of an improved cookstove can reduce burn risk for households that use them.
The Alliance has worked to address the adoption of clean and efficient cookstoves but also on increasing access to the clean cooking fuels, such as ethanol, LPG, solar, and biogas. Beyond child pneumonia and burns, there are other important health benefits that can be achieved through the uptake and sustained use of demonstrably clean stoves and fuels. These include adverse pregnancy outcomes (like low birthweight), cognitive effects, maternal health, cataracts, cancer, and chronic cardiopulmonary disease.
We have a public health imperative to ensure that cutting-edge research and evaluation focused on demonstrating the benefits of scaling clean cooking continues. Preliminary results from a study on ethanol stoves and adverse pregnancy outcomes soon to be released point to the ability of clean cooking to improve indicators of maternal health. Studies assessing how key indicators of adult chronic cardiopulmonary disease change as a result of reductions in household air pollution are also currently underway.
The Alliance’s focus since our founding has been on implementing a comprehensive strategy to enable a thriving market for cleaner cookstoves and fuels. In addition to supporting a variety of research studies, and supporting the development of global ISO cookstoves standards, we have also worked with our partners to continue to strengthen the supply chain for cleaner and more efficient cookstoves and fuels by providing financial and capacity building support to enhance the operational and technical capabilities of innovative, early-stage cookstoves and fuels businesses.
We see the development of cleaner and more efficient cooking solutions as an evolutionary process, and have already seen significant progress being made with regards to the quality (both in terms of emissions and fuel efficiency) and durability of stove technologies across tiers of performance, as well as other aspects of business models such as the way products are distributed and sold, and even financed to reduce upfront costs and increase affordability for consumers. The Alliance is also supporting efforts to enhance adoption through awareness and behavior change campaigns to ensure strong and full use of these better quality stoves and fuels for maximum benefits – health, environment, women’s empowerment and livelihood development.
We need to continue to support and scale efforts in line with our comprehensive approach to ensure a sustainable market for cookstoves and fuels which over time will see increased adoption of clean cooking solutions to ensure cooking no longer kills.