Candle season is in full effect as winter days quickly approach. Candles are a great accent to incorporate into home decorations and also to photograph as the little flickering flames in the jar illuminate dark evenings at home. Scented candles are nice to look at and even nicer to breathe in, but your favorite candle can cause more damage than you imagine.

In the age of social media influencers and luxury brands promoting their one-of-a-kind scents, it’s no wonder why candle sales are soaring. But there is a dark truth hidden behind the feel-good aromas and warm coziness that candles convey — disease and pollution.

The majority of manufactured candles are made from paraffin wax, which is a byproduct in the petroleum refining chain. In a sense, it’s the bottom of the barrel or the worst of the worst. When certain candles are burned, they release toluene and benzene, both of which are known carcinogens.

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In a study by Southern Carolina State University, researchers compared petroleum-based and vegetable-sourced candles to determine their emissions. Researchers let candles burn for up to six hours in a small box and collected and analyzed air quality. The study concluded that candles that are paraffin-based (the most popular kind) emitted toxic chemicals such as toluene and benzene.

“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 Ruhullah Massoudi, a chemistry professor at Southern Carolina State University. “None of the vegetable-based candles produced toxic chemicals.”

Fragrance is also dangerous, because “over the past 50 years, 80 to 90 percent of fragrances have been synthesized from petroleum and some of the commonly found harmful chemicals in fragranced products include acetone, phenol, toluene, benzyl acetate and limonene,” according to a 2009 study, Fragrance in the Workplace is the New Second-Hand Smoke by the University of Maryland.

A 2001 EPA report mentions that burning candles indoors can cause air pollution and “may result in indoor air concentrations of lead above EPA-recommended thresholds.” The lead found in the soot comes from the metal-core wicks that help keep the wick upright.

If you must keep a candle or two in your home, the safest option is to purchase unscented organic soy or beeswax candles. Essential oil diffusers are also a great way to keep your home smelling fresh this holiday season or year-round.

Via Treehugger

Images via Tatlin