Health experts are warning about the dangers of scented candles and incense this holiday season as evidence mounts that they can cause cancer.
In an op-ed in Conversation, two leading researchers from Ireland warned that scented candles, popular year-round, release toxic gases such as carbon monoxide, chemicals and various volatile organic compounds (VOCs).
The harmful gases and chemicals emitted can cause coughing, sneezing, and irritation of the eyes, nose, throat, and lungs.
Their study on the subject and several others show that vapors from burning candles can also increase the risk of heart disease, lung cancer and chronic bronchitis.
People most at risk are in small homes and poorly ventilated rooms, such as a small apartment, bedroom, or bathroom.
Drs Asit Kumar Mishra from University College Cork and Marie Coggins from the University of Galway urged caution by using them in a new op-ed: ‘The use of scented candles or smoking, when combined with blocked wall vents and closed windows, worsens homeowners’ exposure to indoor air pollutants.’
“When using scented candles, for example, maximum concentrations of fine particles can increase up to 15 times the limits prescribed by the World Health Organization.”
They added: “Some of the organic compounds emitted by home fragrance products, such as benzene, phthalates and formaldehyde, can cause cancer, and burning scented candles and incense sticks indoors is a major source of formaldehyde.” .
Burning Christmas-scented candles and incense can release toxic gases such as carbon monoxide, formaldehyde, and volatile organic compounds, which can irritate the respiratory system and increase the risk of heart disease, lung cancer, and chronic bronchitis.
Candles are popular not only for their pleasant aromas, but also for the aesthetic appeal they bring to interior decoration. They are used in more than 70 percent of homes.
Burning scented candles indoors releases a mixture of aromatic substances that remain in the air, including chemicals such as aldehydes, hydrocarbons, and alcohols.
Some harmful compounds, such as naphthalene, anthracene, and pyrene, are known to cause cancer.
In a 2014 study backed by the EPA, researchers tested a dozen samples of scented candles to see what chemicals they released when burned.
They found 34 key compoundsincluding VOCs and other harmful chemicals, such as formaldehyde and acetic acid, which have been shown to cause potentially serious respiratory problems and skin irritation from short-term exposure, and cancer, asthma, cognitive impairment, and chronic respiratory problems when they are exposed. for a long period of time.
Even brief exposure to candle smoke has been shown to reduce cognitive function.
In one study, participants’ cognitive scores on a specific test averaged 48 before exposure, classified as “average” cognition.
After exposure to contaminants from a burning scented candle, their scores dropped to an average of 40, classified as “below average” cognition.
The researchers who wrote the opinion article. conducted his own study This week they measured the air quality of 14 homes in Galway, Ireland, 24 hours before and 24 hours after making changes to improve the home’s energy efficiency.
In one study, on average, about 60 percent of exposure to small airborne particles, which can be inhaled deep into the lungs and enter the bloodstream, came from burning candles.
Around 20 million cases of cancer were diagnosed in 2022, but that number is expected to rise to more than 35 million cases by 2050. Air pollution, such as from scented candles, is a leading cause of cancer of lung.
The researchers measured five pollutants, including CO2 and PM2.5 (small particles that can enter the lungs and bloodstream), along with temperature and humidity in two rooms of each home.
PM2.5 particles, invisible to the naked eye, come from car engines, burning wood and tobacco smoke. Pollution measuring devices were placed one meter above the ground near sources of pollution and ventilation, while occupants recorded their household activities, such as cooking, opening windows and lighting candles.
The results revealed that activities such as lighting candles, smoking and blocking wall vents can be detrimental to indoor air quality by increasing PM2.5 and CO2 levels.
The two doctors said: ‘In non-smoking homes, the use of candles may be the main source of particle pollution.
‘Some of the organic compounds emitted by home fragrance products, such as benzene, phthalates and formaldehyde, can cause cancer, and burning scented candles and incense sticks indoors is a major source of formaldehyde.
A 2013 study in the journal Environmental science and technology found that lighting candles was a major source of fine airborne particles that can cause breathing problems, increase the risk of heart attack and stroke, and affect brain function.
They measured particle concentrations in the air and found that particle levels remained elevated for hours after the candle flame went out.
On average, candle burning was responsible for about 60 percent of total exposure to tiny airborne particles, small enough to be easily inhaled deep into the lungs and even entering the bloodstream.
A 2020 survey found that about a quarter of candle users reported health problems potentially related to candles, such as headaches, shortness of breath, and cough.
Using scented candles and incense in small rooms and bathrooms, especially where ventilation is poor, compounds the dangers by exposing the person to higher concentrations of harmful chemicals.
A 2020 survey in Saudi Arabia revealed that 66 percent of people who responded to researchers’ questions used scented candles and 34 percent used them more than four times a month.
About a quarter of people reported health problems that could be related to candle use, including headaches (reported by 15 percent), shortness of breath (nine percent) and cough (eight percent). .
Longer exposure (more than 60 minutes) was associated with more headaches, sneezing and wheezing, although not significantly so.
The researchers concluded: “This finding suggests that the emission of VOCs, phthalates and (particles) from burning scented candles like other fragrances may be a reason for the development of these adverse symptoms.”
The ingredients in a scented candle are often a mystery because there is no federal requirement requiring companies to list them anywhere.
Instead, the Consumer Product Safety Commission recommends (but does not require) manufacturers to disclose any potentially hazardous ingredients, such as lead in wicks or harmful chemical fragrances.
As long as the candles burn in well-ventilated spaces, the risks of damage will be minimal.
HVAC expert Jessica Wicks told Real Simple: ‘Consumers should avoid lead or metal wicks and paraffin wax candles.
‘You should choose soy, beeswax or coconut oil candles with cotton wicks. Higher quality candles are more expensive, but usually last longer.’