The aroma of pumpkin, apple or cinnamon-scented candles wafting through our homes is comforting, reminding us that the festive fall season has arrived. However, certain types of candles emit toxic chemicals called volatile organic compounds, or VOCs. These include benzidine, acetaldehyde, and formaldehyde that have been linked to increasing the risk of cancer, says Health.

Another VOC called toluene may be released from paraffin-based candles. Without proper ventilation, toluene can cause irritated eyes, nose and throat, headache, dizziness, confusion and anxiety, says the Occupational Safety and Health Administration (OSHA).

While the concentration of VOCs from scented candles is lower than those emitted from tobacco smoke, and other products such as glues, paints, construction materials and other occupational hazards, experts say the chemicals are not something you want to breathe on a regular basis.

Be careful about burning scented candles around people — especially children ─ with asthma or allergies, especially in an area that’s not well ventilated.

Avoid candles made from paraffin and choose those made from soy or beeswax.

“These are not only good because you are avoiding the paraffins, which release toxic chemicals, but they also tend to burn slower and produce less soot,” says Jennifer Dunphy, author of The Toxin Handbook for Families: What You Need to Know to Protect Your Family in a Modern World.

She recommends buying candles scented with natural oils instead of synthetic fragrances and those that are undyed. Wax warmers are a good alternative but it’s also important to select products that are not strongly scented or made from paraffin.

To avoid the health hazards of scented candles altogether, try boiling water with fragrant herbs, fruit and spices, says Dunphy. “They smell great and have no known health risks,” she adds.