A lit candle can create a pleasant atmosphere, but according to scientists, it can also worsen the air quality in the home. According to new research, smoke from candles burning indoors – especially in rooms without adequate ventilation – contains a mixture of chemicals that increase the risk of certain types of cancer. Therefore, experts draw particular attention to scented candles, whose synthetic perfumes can increase the amount of pollutants in the domestic air.
A common material used in the manufacture of candles is paraffin. It is a by-product of oil refiningwhich is cheap and binds scent and color well. Some manufacturers refer to it as mineral wax, but it is actually the same petroleum material. When burning paraffin candles small amounts of volatile organic substances, such as benzene, toluene or formaldehyde, may be released into the air. These substances are produced during combustion and in higher concentrations they can irritate the respiratory tract and are classified as carcinogenic.
Another source of emissions can be synthetic fragrances. Some of them release phthalates – chemical substances that prolong the duration of the fragrance and according to some studies, they disrupt the hormonal system. When burning candles, hydrocarbons are also produced, for example alkanes and alkenes, i.e. substances normally present in car exhaust gases.
Additionally, paraffin candles can produce more soot than vegetable wax candles, especially if the wick is too long or the candle burns unevenly. The highest concentrations of pollutants occur in unventilated rooms where combustion products accumulate. Candle smoke also contains soot, nitrogen dioxide and polycyclic aromatic hydrocarbons, which have been linked to inflammation and an increased risk of cancer.
Scientists therefore recommend using candles sparingly, shortening the wick, not letting them burn in a draft, not letting them burn for too long, and ventilating the room after using them. People with asthma or other chronic respiratory diseases, children and the elderly should be especially careful.
