Kerosene: A Widely Used Fuel with Unknown Health Risks
By: Megan Avakian
In developing countries, kerosene is often advocated as a clean alternative to solid fuels, like wood or coal, for use in cooking. Globally, an estimated 500 million people also commonly use kerosene as fuel for lamps. But new research is bringing the potential health risks of exposure to kerosene combustion products to light.
Epidemiologic studies have linked household kerosene use to impaired lung function, asthma, cancer, and increased susceptibility to infectious diseases such as tuberculosis. However, a recent review of household uses of the fuel and its hazards in low- and middle-income countries conducted by Michael Bates, Ph.D., an NIEHS grantee and adjunct professor of epidemiology at the University of California, Berkeley School of Public Health and colleagues concluded that the quality of these studies was variable and that they generated inconsistent results. To improve the interpretability of future epidemiologic studies, the team concluded, researchers need to consider fuels separately and take into account user behaviors and device types.
“Previous epidemiologic studies have tended to disregard kerosene, assuming it to be a clean fuel, and often combining it with liquefied petroleum gas or electricity in the reference category against which to assess health impacts of solid fuels. However, it is important to consider kerosene separately from other fuels when carrying out studies of the health impacts of fuels in developing countries,” said Bates.
Combustion products generated by many kerosene-burning devices include considerable amounts of fine particulate matter, carbon monoxide, nitric oxides, sulfur dioxide, formaldehyde, and polycyclic aromatic hydrocarbons (PAHs) - compounds that can cause a range of adverse health effects including respiratory ailments, cancer, and death.
“Kerosene lamps have seldom been considered in studies of the health impacts of fuels in developing countries,” said Bates, who posits that this is probably because lamps consume a relatively small amount of fuel compared to stoves. However, he said, this “overlooks the fact that exposure to emission products from lamps may be considerable due to the close proximity of the user, often for extended periods of time in the evening.” Bates found that kerosene use, especially for lighting, was associated with tuberculosis in Nepal.
Bates and his colleagues have also found associations of household kerosene use with low birth weight, and childhood pneumonia. With support from NIEHS they are conducting further study of tuberculosis risks associated with kerosene use in Nepal, and are also examining personal exposures to PAHs, which kerosene combustion produces in large amounts. He hypothesizes that PAHs play a role in health effects associated with kerosene use. “I predict that over the course of this decade, kerosene fuel use will become a major topic of environmental health investigation and the extent of any health impacts will become much clearer. If kerosene is proven to be harmful, then policies and subsidies intended to help the poor afford the fuel will need to be reconsidered,” said Bates, who is hopeful a consensus on the degree of the safety or harmfulness of kerosene will emerge quickly.
Citation: Kerosene: a review of household uses and their hazards in low- and middle-income countries. Lam NL, Smith KR, Gauthier A, Bates MN. J Toxicol Environ Health B Crit Rev. 2012; 15(6): 396-432. doi: 10.1080/10937404.2012.710134. Review. PMID: 2293456 [Abstract]