Scientists have warned that burning candles indoors—especially scented ones—can release harmful pollutants linked to cancer and respiratory disease.

According to researchers in Denmark, candles are one of the biggest contributors to indoor air pollution in many homes. Experiments show that burning candles produces ultra-fine particles, toxic gases and chemicals that can accumulate quickly in poorly ventilated rooms.

A key 2017 study that found paraffin candles emit hazardous materials, including benzene and toluene, was published in the ‘International Journal of TROPICAL DISEASE Health’.

To this end, experts advise limiting candle use indoors, trimming wicks to reduce soot, and ventilating rooms by opening windows. LED candles or plant-based wax alternatives may offer safer options.

“Burning candles may seem harmless, but in poorly ventilated spaces they can significantly affect indoor air quality,” the researcher warned.