It’s the time of year to get cosy indoors with some scented candles and maybe a warm cup of hot chocolate.   

And as appealing as that may sound, the pollutants they produce when burning pose risks to our airways – sometimes life-threatening.

Children are the most at risk, according to first aid expert Emma Hammett, who reveals that dust mites in the home are a leading trigger for asthmatics.  

But some may argue that nothing says Christmas more than the smell of a spicy scented candle.

However, be aware that candles and incense let off particles such as volatile organic compounds (VOCs) – compounds that easily become vapours or gases.


VOCs are released from burning fuel such as gasoline, wood, coal, or natural gas as well as from many consumer products such as cigarettes, scented candles and solvents. 

Carpets, vinyl flooring, cleaning products, cosmetics, hairsprays, paint, heating, and cooking fuel all cloud household air with VOCs. 

VOCs are blamed by numerous studies for triggering asthma in children and worsening it in adults, and raising the risk of heart disease. 

Breathing in the irritant can inflame the eyes, nose and throat, cause difficulty breathing, nausea, and damage the central nervous system.

Candles also let off formaldehyde when they burn, a pollutant which is known to be harmful to health over the long term. 

Formaldehyde was first classified as a probable human carcinogen in 1987 by the US Environmental Protection Agency (EPA). 

Since then, some studies of humans have suggested that formaldehyde exposure is associated with certain types of cancer, leading to it being named as a known carcinogen in 2011, by the National Toxicology Program.


One study at York University discovered a commonly used ingredient in citric-scented scented candles called limonene reacts with the air creating formaldehyde. 

The study revealed concentrations of limonene in scented candles were up to 100 times higher than previously thought.

The study warned fragrance chemicals could completely dominate the inside of our homes, meaning more exposure to formaldehyde.

The study concluded with the recommendation of opening doors or windows after burning a scented candle or spraying air freshener.

On top of this, incense sticks give off 100 times the amount of fine particles as a scented candle. 

The British Lung Foundation advises you don’t light several scented candles or incense sticks in a confined space such as a bathroom. However occasional use is okay.

Good to know: Houseplants such as geraniums, lavender and types of fern would found to remove formaldehyde from the atmosphere.


-Daily Mail