Though they release a small amount of VOCs into the air, there isn’t enough strong evidence to say they’re dangerous to your health

There’s a reason candles play a role in religious traditions and mindfulness practices around the world. Fire is foundational to human life, and we respond to it accordingly.

It’s little wonder then that so many of us love burning candles, especially scented candles, in our homes.

But are candles bad for you? Pulmonologist Renee Dixon, MD, discusses the possible dangers candles may pose to your health and how to safely burn them.

Can burning candles be bad for your health?

Burning candles can contribute to indoor air pollution, but what the medical and scientific community is split on is whether or not the emissions they generate, tiny as they are, can meaningfully impact your health.

So, are candles toxic?

Given all the available research, Dr. Dixon says she isn’t concerned for people who choose to light them up (in a well-ventilated space, at least).

What happens when you burn a candle?

You may have heard of volatile organic compounds or VOCs. As a candle burns, it releases hydrocarbons — chemical compounds consisting of hydrogen and carbon — into the air. In particular, burning candles releases trace quantities of toluene and benzene.

Toluene is commonly used in paint thinners and adhesives. Without proper ventilation, toluene exposure can irritate your eyes, nose, throat and skin. It can also cause headaches, dizziness, confusion and anxiety.

Benzene is a gas emitted by forest fires, volcanoes, and burning coal or oil. Benzene is primarily used in industrial and pharmaceutical settings, but the vast majority (90%) of all benzene exposure occurs as a consequence of smoking. Benzene is carcinogenic, having been found to increase the risk of leukemia and other blood cancers.

Who’s at risk?

While you wouldn’t want to breathe in significant quantities of either toluene, benzene or any other hydrocarbons, the small amount released when you burn a candle is only cause for concern in certain situations.

Do candles cause cancer? Dr. Dixon says a small number of studies suggest an association between candle burning and bladder cancer.

“All these volatile organic hydrocarbons accumulate in the blood,” she explains. “They eventually get excreted through the bladder, hence the link with bladder cancer.”

As a result, Dr. Dixon says people under surveillance for, living with or in remission from bladder cancer might want to go easy on the candles. Likewise, she encourages people with chronic lung conditions like chronic obstructive pulmonary disease (COPD) to be mindful of the levels of air pollution in their homes.

But it’s important to note that the science isn’t strong enough to suggest we should stop buying and burning candles.

In fact, we engage in far higher-risk activities every day. For example, Dr. Dixon says indoor cooking increases the particulate matter in the air and has been linked to respiratory illnesses. A scented candle simply isn’t dangerous by comparison.

“There is no imminent danger,” she states. “You just have to be mindful about investing in high-quality candles and keeping them in well-ventilated areas.”

Are some waxes better than others?

Wax type and quality can change the amount and kind of emissions the candle generates. While there’s no definitive science proving it does any harm, Dr. Dixon suggests avoiding paraffin wax. Paraffin is made from petroleum and seems to generate greater emissions than other waxes. And candles made from paraffin tend to be cheaper.

“In some cases, these cheaper products have more formaldehyde-generating materials and a lower melting point,” she explains. “It’s been suggested — but not proven — that cheaper candles are more dangerous because they have more VOCs in them.”

If listed, check the paraffin content of the candle you’re considering buying. Whenever you can, opt for beeswax, soy or other plant-based waxes instead.

While they may be pretty to look at, Dr. Dixon also suggests skipping candles that’ve been dyed.

“The dye used to color the candles has benzidine in it,” she reports, which is also linked to an increased risk of bladder cancer.

Are scented candles toxic?

For every person who loves to unwind with a scented candle, there’s another person who gets a headache (or a runny nose) just thinking about them.

There isn’t any science that suggests scented candles are inherently more dangerous than the unscented variety. And like all candles, they release VOCs, but they do so in quantities that shouldn’t pose a health risk. For the safest possible aromatherapeutic adventure, select high-quality candles that don’t use dye or paraffin.

Regardless of toxicity, many people have allergic reactions to scented candles. For some, scented candles can even trigger asthma attacks.

What about wick toxicity?

While once a source of considerable concern, many countries have taken action to prevent the use of lead and metal-cored candle wicks, which can produce dangerous emissions and cause lead poisoning.

Australia was the first country to ban the use of lead wicks. While most American manufacturers stopped using lead in their candle wicks back in the 1970s, the Consumer Product Safety Commission (CPSC) didn’t ban the sale and importation of candles with lead-core wicks until 2003.

If you’re unsure whether your country has banned lead-core candle wicks, just make a point to shop for candles with paper-core, cotton or wood wicks.

How you can safely burn candles

In many cases, the therapeutic benefits of burning candles may far outweigh any health risks they may pose. But that doesn’t mean you can’t make healthy choices to improve the experience and protect against accidents.

Treat yourself to high-quality candles

While expensive candles may be bad for your wallet, they’re a good investment in your health.

“Studies suggest that lower-quality candles emit more particulate matter and chemicals,” reiterates Dr. Dixon. “Higher-quality candles burn off very slowly.”

So, if you’re looking to minimize risk, stick with the fancy stuff.

Of course, the safest candle in the world is only as safe as the person burning it. That’s why following candle safety guidelines is crucially important.

Follow fire safety guidelines

If you’re looking for a reason to stop burning candles altogether, the most obvious safety hazard — fire — is also the most significant.

According to the National Fire Protection Association (NFPA), firefighters respond to an estimated 5,910 structure fires in the U.S. that candles cause every year. The result: an average of 74 deaths, 558 injuries, and $257 million in property damage.

While they’re smaller than the fires we burn in bonfires, fire pits and fireplaces, we should still use caution and common sense when interacting with candles. The following safety tips will help keep you and your family safe:

  1. Trim the wick to 1/4 inch.
  2. Use a wick dipper to keep the wax pool clear of debris at all times.
  3. Burn your candle in a well-ventilated room, far removed from anything that could catch fire.
  4. Never burn a candle for more than four hours.
  5. Never leave a candle unattended, and don’t burn it if you may fall asleep.
  6. Instead of blowing a candle out or using a snuffer, use a wick dipper to gently submerge the wick in the wax pool. This method doesn’t generate any smoke or wax splatter.
  7. Don’t attempt to touch or reposition your candle until it’s had time to cool.

Alternatives to candles

If you’d rather avoid candles altogether, but still want the feeling of a lit candle in your home, consider these alternatives:

  • Ghee and oil lamps, like diyas (which are used in multiple religions across the Indian subcontinent), are smoke-free and less toxic than candles or incense.
  • Flameless candles, while certainly not comparable to the real thing, don’t pose a fire risk.
  • If you buy scented candles for the smell, wax melts might be a suitable substitute. Dr. Dixon says the low temperatures used in wax melting result in fewer combustion byproducts.

Final thoughts

So, are candles dangerous? While not all candles are created equal, there isn’t enough strong scientific evidence to suggest that they’re a danger to your health. As long as you’re taking all the proper fire-safety precautions, go ahead and “get lit.”