Scientists from the University of Birmingham State That Burning Scented Candles can be Harmful to your Health

Scented candles are truly just a normal part of our modern age. They're gifted to friends (seriously? 🫣), used to promote a feeling of calm or relaxation, lit to create ambience and often burned in people's homes daily. Ranging from a few dollars to a few hundred dollars, it would be an extreme rarity to find a person that hasn't owned or been gifted a scented candle in their lifetime.

The article asks the question, "apart from being a way to literally burn money, what’s the harm?". While us beeswax lover's may know some of the reasons these seemingly harmless everyday objects aren't so harmless - too few people are actually aware of the many dangers.

It further explains that we often aren't aware or actively thinking about the air quality inside our own homes. The article discusses one Danish study that suggests "burning candles is the main indoor source of pollution particles". 

“We like to make our homes as cosy as possible and candles give us a feeling of comfort, but I think there is a lack of understanding of what the actual effects are,” says Professor Christian Pfrang, Professor of Atmospheric Science at the University of Birmingham. 

According to one study, burning candles is the main indoor source of pollution particles.

Prof Pfrang advises that PM2.5 along with products of incomplete combustion (carbon monoxide (CO), nitrogen oxides (NO) and sulphur dioxide (SO2)) can all be released while burning and scented candle where they are then breathed into our lungs.

Unhealthy levels of PM2.5 can increase the risk of health issues including: heart disease, asthma, and low birth weight. Short term exposure to SO2 can also harm the respiratory system. Prof Pfrang is also quoted addressing who can be greatly impacted by these pollutants,

“People with pre-existing conditions such as asthma or COPD as well as vulnerable groups, such as children and the elderly, are particularly sensitive to these effects,” 

“Sulphur oxides can also react with other compounds to form particles, which can penetrate deeply into our lungs and contribute to severe health problems.”

Prof Pfrang proceeds to explain that there are growing links between candle burning with these chemicals and their impacts on cognitive and mental health. While in its early stages of development, Prof Pfrang says there are other academics who have begun to link long term health conditions such as Alzheimer's and Dementia to air pollution. 

Proof That Scents Cause Harm

When scents are added to a candle, the risks increase.

Prof Pfrang is quoted in the article,

“Scented candles release aldehydes, such as formaldehyde in particular, and these are quite bad for health,”

Aldehydes can irritate the skin, throat, lungs and eyes, further causing headaches, worsen allergies and can even cause dizziness. They are also carcinogenic. 

Not even essential oils are harmless when used in candles. Due to the concentrations being much higher in essential oils rather than in nature, they can trigger allergic reactions, according to Prof Pfrang.

While the majority of these chemicals become more dangerous once burning, the article outlines that studies have shown some of these harmful elements can be emitted even when a scented candle isn't yet burning, like VOCs.

The Article Isn't Entirely Accurate

The article then goes on to quote a study (funded by a soy wax producer without explicitly detailing that), that suggests soy wax candles are better than paraffin wax candles - even suggesting they burn like beeswax... 

"A 2002 study published in the Journal of the American Oil Chemists’ Society found that soy wax, much like beeswax candles, burned at a significantly lower rate and resulted in less soot than paraffin candles. "

Note they say 'less soot than paraffin'. Soy wax candles, particularly scented soya wax candles DO NOT burn as cleanly as beeswax if you read the results of the full study.

Prof Pfrang does however recommend candles made of natural material.

“Importantly, remember non-scented candles don’t release harmful aldehydes. A cotton wick is also best.”

Thanks Prof Pfrang!  We like natural, non-scented, safe candles too!

How To Burn A Candle, The Clean Way.

Prof Pope says,

“A candle that is burning nicely has very little particulate matter air pollution.”

“You can see when they’re sooty and creating smoke. And if you can see smoke, there’s air pollution.”

It is advised to keep the wick the correct length, check for sputtering and not to burn candles for prolonged periods of time. Prof Pfrang also suggests not to burn them in a bedroom saying,

“Particulates can stay in the room for many, many hours.”

Can We Reduce Indoor Air Pollution?

Ventilation, hours spent burning and other things come into play when trying to reduce indoor air pollution.

“If you burn one candle in a large room for a short time the pollution will be quite limited, but if you have many candles in a poorly ventilated area, it’s a different situation,” - Prof Pfrang. 

“Every candle has a certain emission profile and if you have twice as many you double it. It very quickly builds up.”

The article then goes on to suggest that we should replace candles with electric candles... Seriously? Playing football on Xbox does not give you the same benefits as playing football in the field.  A conversation with a chatbot is not the same as a conversation with a friend (regardless of what Elon says). And we don't get as good nutrition from processed food as real food.  So too we don't get the same relaxation or ambience from a fake candle flame flicker as a pure, golden hued, smoke free, pure beeswax candle.