This article by Chen, Ma, and Fontaine provides a unique perspective through a natural experiment that resulted from the severe ice storms of 2008 in Hunan Province, China. It is an elegant example of “shoe leather” epidemiology and investigation conducted by the Chinese Centers for Disease Control and Prevention in collaboration with the U.S. Centers for Disease Control and Prevention.
As the authors point out, the individuals who suffered from carbon monoxide (CO) poisoning had no occupational exposure; the poisonings were simply the unfortunate result of a natural event that impacted residents for a period of almost two months. The causes of the poisonings during the storm event centered around poorly ventilated stoves, improper selection of stoves, and stoves that were too old and not functioning well. The basic public health message is one that can be applied almost anywhere in the world: improperly ventilated stoves should not be used for supplemental heat, especially in bedrooms and sleeping areas. Of course, that is much easier said than done. It is interesting to note that the incidence of CO poisoning was significantly higher in urban areas than in rural areas, with an incident rate that was nearly 10 times higher in urban settings.
McCracken et al.1 and Smith et al.2 report that approximately half of the world's households depend on biomass (e.g., wood, crop residues, and animal dung) and coal for cooking and heating. Most of this solid-fuel use occurs in developing countries, where poor households generally use open fires or inadequately vented stoves. These fuel-stove combinations result in high indoor levels of fine combustion-generated particles and other pollutants. Proper ventilation and maintenance of these stoves greatly reduces harmful effects from particulates and other combustion products, including CO. Novel and inexpensive programs supported by the World Health Organization and others have proven to be effective in reducing tragic outcomes such as the incident in Hunan.
REFERENCES
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