Frequent use of certain candles produces unwanted chemicals

Monday, August 24, 2009

Long-term exposure to emissions of certain types of candles could be hazardous to human health and cause poor indoor air quality, according to researchers in the 1890 Research & Extension Program at SC State University.

Lead researcher Dr. Ruhullah Massoudi and SC State alumnus Amid Hamidi ‘09, who worked with Massoudi while earning his bachelor of science in chemistry, tested various brands of paraffin wax (petroleum-based) and soybean (vegetable-based) candles. The candles were non-scented, non-pigmented and used no dyes.

The candles were placed in an enclosed specially constructed chamber for up to six hours to trap and test the emitted gases of the burning candles. A GC/MS test was conducted to analyze the contents of gaseous products. The chromatograms of the paraffin candles revealed some undesired chemicals, such as alkans, alkenes and toluene, all reported to cause harmful effects to humans.

“The paraffin candles we tested released unwanted chemicals into the air. For a person who lights a candle every day for years or just uses them frequently, inhalation of these dangerous pollutants drifting in the air could contribute to the development of health risks like cancer, common allergies and even asthma,” said Massoudi, a chemistry professor in the Department of Biological and Physical Sciences. “None of the vegetable-based candles produced toxic chemicals,” he added.

According to Massoudi, the undesired chemicals of the paraffin candles were emitted because the candles are by-products of oil refineries, while the soy candles are by-products of vegetables which generally are not harmful to people.

Massoudi’s research stems from a desire to address a possible public health concern, boost the American agricultural economy and promote sustainability.

Most consumers purchase the usually inexpensive petroleum-based candles to fragrant an environment or inspire a mood. Massoudi noted, a possible increase in production and demand for soy candles could attribute to a decline of health risks caused by paraffin candles and help disadvantaged small farmers diversify their crops to yield more revenue. Soy wax components, cites Massoudi, are also renewable and biodegradable.

The candles emissions study is funded by 1890 Research & Extension, a federal and state funded program that helps ensure SC State achieves its land-grant mission of improving the lives of limited resource individuals, families and communities through research, teaching and service.

For more information on the study, contact Dr. Ruhullah Massoudi at (803) 536-7112 or