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Member Research & Reports

Member Research & Reports

UNC Study: Burning Synthetic Fireplace Logs May Increase Breast Cancer Risk

‘Tis the season to be burning synthetic fire logs, but a new study from The University of North Carolina’s Gillings School of Global Public Health reports that using these prepackaged fireplace staples also could increase the chances of developing breast cancer.

[Photo: Ms. Alexandra White (left) led the UNC study on breast cancer risk for women who used synthetic fire logs. Fireplace photo by Mr. Sean Drellinger]

The study, published online December 12 in  Environmental Health, is titled “Indoor Air Pollution Exposure from Use of Indoor Stoves and Fireplaces in Association with Breast Cancer: A Case-Control Study.” Wood and synthetic logs are sources of polycyclic aromatic hydrocarbons (PAHs), which cause mammary cancer in animal experiments, and both contribute to residential air pollution, but researchers found that only the synthetic logs were found to be associated with an increased risk of breast cancer.

“Certainly the burning of real or synthetic logs releases toxic pollutants into the air, but we found that burning synthetic logs significantly increased the risk of developing breast cancer, whereas burning the wood logs did not,” says Ms. Alexandra White, epidemiology doctoral student in the Gillings School and the study’s first author. “The fact that the association with breast cancer risk was found only with synthetic logs was a surprise, which means our research should be interpreted with care and should be repeated by others. We also found a stronger association between synthetic log burning and breast cancer risk with more years of exposure to burning synthetic logs and in women with certain genetic variations that may make them more susceptible to PAHs,” Ms. White said.

This study was part of the Long Island Breast Cancer Study Project, which is focused on identifying environmental risk factors for breast cancer. Dr. Marilie Gammon, epidemiology professor at the Gillings School, is principal investigator for that project.

The study examined 1,508 cancer cases with 1,556 controls. Among all study subjects, 747 reported using a fireplace or indoor stove at least three times per year in one of their Long Island residences. Of these, 246 cases (16.4 percent) and 202 controls (13.0 percent) burned synthetic logs. In the synthetic log users, breast cancer risk was increased by 42 percent in association with burning synthetic logs in the fireplace or indoor stove.

Ms. White cautions that the results are not definitive and further study was needed.

“Because wood burning was not found to be associated with breast cancer risk, this association should be replicated in other study populations,” she says. “We were also unable to differentiate between use of closed indoor stoves versus open fireplaces, which may contribute differently to indoor air pollution levels.”

Ms. White adds, however, that the high incidence of breast cancer in the U.S. and the relatively common prevalence of indoor stoves and fireplaces suggest that this research, if confirmed, may have considerable public health importance.

The full study can be found in Environmental Health.