Most of us are familiar with outdoor air pollution, but did you know that the air inside our homes can be more toxic than the air outside? Common household products like air fresheners, cleaning products and scented candles and incense contribute significantly to indoor air pollution.
Recent studies on Irish homes after energy retrofits found that activities like burning candles, smoking, and blocking ventilation can significantly impact indoor air quality. When scented candles or incense sticks are burned in poorly ventilated spaces, fine particle concentrations can rise to 15 times the World Health Organization‘s prescribed limits, taking hours to return to normal.
Toxic Chemicals in Air Fresheners
Air fresheners directly release or contribute to the formation of harmful substances, including volatile organic compounds (VOCs), benzene, formaldehyde, toluene, and phthalates. Similarly, burning candles and incense produces toxic gases such as carbon monoxide, sulfur dioxide, and nitrogen oxides, along with VOCs.

These pollutants can trigger coughing, sneezing, and irritation of the eyes, nose, and throat. Long-term exposure is linked to serious health risks, including heart disease, lung cancer, and chronic bronchitis, and can worsen asthma symptoms.
Research from Purdue University warns that chemicals in air fresheners and floor cleaners react with ozone, generating toxic nanoparticles. These can penetrate deep into the lungs, further deteriorating air quality.
Healthier Alternatives
To improve indoor air quality, opt for natural alternatives like essential oil diffusers, houseplants, or simply increasing ventilation. Reducing the use of artificial fragrances can create a cleaner and safer indoor environment.