Environmentalist concerns about deforestation have driven the development of many new types of cooking stove that either have increased efficiency or use less polluting fuels (http://www.esmap.org/
). The lower smoke output observed with these stoves has allowed health professionals to use them in trials as health interventions. However, systematic evaluations have shown that there are practical barriers to stove adoption (Barnes et al., 1994
). The technical complexities of stove design, lack of maintenance and users’ behaviour, which modify ideal combustion, have also led to highly variable stove performance in everyday use compared with laboratory testing.
To be effective, interventions must take into account specific local conditions such as variations in the natural environment and climate, the purposes of energy use (e.g. cooking vs. heating), local infrastructure, user behaviours and sociocultural circumstances. For instance, changes in housing and having a separate kitchen or additional windows can reduce exposure, although reductions are likely to be smaller for those who cook and remain close to their fires. Moreover, burning fuel more cleanly by pre-processing it may be appropriate depending on geographical location, e.g. using charcoal in parts of sub-Saharan Africa or biogas in parts of Asia.
The first randomised controlled trial performed on the health effects of solid fuel use in Guatemala, using the ‘plancha’ chimney stove (A and B), was recently reported (Diaz et al., 2007
). This challenging fieldwork revealed that exposure to smoke, measured using exhaled carbon monoxide as a surrogate marker, was reduced with the plancha, as were symptoms of sore eyes and back pain. However, as yet there are no published spirometric, birthweight, ALRI rate or other health data.
(A) Traditional open fire and (B) plancha stove. Images by Nigel Bruce.
Current understanding suggests that lower emissions will be more effectively achieved in the poorest communities by modifying specific aspects of current fuel stove and energy use behaviours rather than by attempting to replace the solid-fuel stoves with stoves that use liquid fuel, gas or electricity. For communities that already purchase some or all of their BMF and where supply of clean fuels is (or could become) cheaper and more reliable, then development initiatives to support a switch to LPG or other liquid or gaseous fuels has a higher chance of success.
shows the nature of possible solutions to reducing BMF smoke (Bruce, 2005
). Given the number of potential strategies and the wide range of agencies responsible for these interventions, it may be thought that health services have little or no role in addressing this problem. Health services might be seen as being at the receiving end of the consequence of biomass smoke but not in a good position to do anything effective about it.
Potential interventions to reduce exposure to indoor air pollution
However, this would miss the important input that health professionals can have. In their contact with patients with pneumonia, COPD and other health issues, health professionals can assess the risks, raise awareness and provide guidance on reducing exposure. Public health education and ‘brief interventions’ by clinicians have been shown to have a significant impact on disease burden (Rigotti et al., 2007
). This topic also provides important opportunities for clinical and epidemiological research, the findings of which can be very influential within a country. Those within the health system responsible for planning and management can make good use of information from healthcare and local research, and contribute to awareness-raising through the media and educational activities, as well as lend their voices to calls for action at local, national and international forums.