8 September 2003

Mosquito Coils May Cause Cancer

by Kate Melville

The mosquito coil made in some Asian countries that people often use to ward off mosquitoes may be releasing cancer-causing smoke, scientists at UC Riverside report in the journal Environmental Health Perspectives.

The scientists - Bob Krieger, Travis Dinoff and Xiaofei Zhang of the department of entomology - sampled coils from Asia on sale at markets in Southern California and found that they contained "S-2" or octachlorodipropyl ether, banned for sale in the United States.

"It is very possible that the coils are exposing users to bischloromethyl ether, also called BCME, a potent lung carcinogen," said Krieger. "High exposure can occur if the coils are used overnight, as they often are."

Because of mosquito-borne diseases such as West Nile virus, the use of these mosquito coils may be on the increase. "These coils purchased in stores in the United States do not list S-2 as an ingredient," said Krieger. "This suggests that illegal, unregistered products are able to find their way into the American market."

For their research, the authors sampled more than 50 coils collected from Asia and California. "Next, we plan to measure levels of BCME in indoor environments where the coils are used," said Krieger. "We hope that epidemiologists will take an interest due to the number of people exposed and the potency of BCME."