This has been posted in various websites such as:


Is it just another hoax? I wish it were. After all, the old mosquito coil is such a cheap and readily available product for people in mosquito-infested areas. It can effectively (80%) keep mosquitoes away for up to 8 hours in one session.


A quick search and found that it is indeed not a hoax.


1.          According to “Recent studies showed that the smoke generated from burning mosquito coil is of certain health concerns – one burning mosquito coil produces the same amount of particulate mass (diameter up to 2.5 μm) as 75-137 burning cigarettes would; and the emission of formaldehyde from one burning coil can be as high as that released from 51 burning cigarettes.”


2.          This is based on research findings by a team led by Weili Liu, et al, in a “Joint Graduate Program in Exposure Measurement and Assessment” of the University of Medicine and Dentistry of New Jersey (UMDNJ) and Rutgers University, 170 Frelinghuysen Road, Piscataway, NJ 08854, USA. The team consists of Liu, Weili, Junfeng Zhang; Jamal H Hashim, Juliana Jalaludin and Goldstein, Bernard D. (September 2003). Jamal is from the Department of Community Health, National University of Malaysia and Juliana is from the Department of Community Health, Universiti Putra Malaysia.


3.          The research was published in "Mosquito Coil Emissions and Health Implications". Environmental Health Perspectives 111 (12): 1454–1460. doi:10.1289/ehp.6286. PMC 1241646. PMID 12948883  [Environmental Health Perspectives (EHP) is a monthly journal of peer-reviewed research and news published by the U.S. National Institute of Environmental Health Sciences, National Institutes of Health, Department of Health and Human Services]


4.          The following is the abstract (slightly edited) of that research finding. It is from a website of the U.S. government-funded national resource for molecular biology information: :


4.1“Burning mosquito coils indoors generates smoke that can control mosquitoes effectively. This practice is currently used in numerous households in Asia, Africa, and South America. However, the smoke may contain pollutants of health concern. We conducted the present study to characterize the emissions from four common brands of mosquito coils from China and two common brands from Malaysia. We used mass balance equations to determine emission rates of fine particles (particulate matter < 2.5 microm in diameter; PM(2.5)), polycyclic aromatic hydrocarbons (PAHs), aldehydes, and ketones.”


4.2 “Having applied these measured emission rates to predict indoor concentrations under realistic room conditions -

·       we found that pollutant concentrations resulting from burning mosquito coils could substantially exceed health-based air quality standards or guidelines.

·       Under the same combustion conditions, the tested Malaysian mosquito coils generated more measured pollutants than did the tested Chinese mosquito coils.

·       We also identified a large suite of volatile organic compounds, including carcinogens and suspected carcinogens, in the coil smoke.

·        In a set of experiments conducted in a room, we examined the size distribution of particulate matter contained in the coil smoke and found that the particles were ultrafine and fine.”


4.3 “The findings from the present study suggest that exposure to the smoke of mosquito coils similar to the tested ones can pose significant acute and chronic health risks. For example, burning one mosquito coil would release the same amount of PM(2.5) mass as burning 75-137 cigarettes. The emission of formaldehyde from burning one coil can be as high as that released from burning 51 cigarettes” [The Full Text of this article is available as a PDF (341K)].

So, next time you find yourself in a room with a mosquito coil burning, what would you do?