Incense and candles share a ton of similarities. Both candles and incense date back to ancient times, require a flame, slowly release fragrance into a room, and generally improve a room’s aroma. But in an era where health and safety are priorities #1 and #2, which is the safer option between incense vs. candles?

Here’s the TL;DR:

Incense is generally safer than candles due to the lesser fire risk. However, candles are typically safer regarding the impact on human health. Some studies suggest burning incense can cause cancer due to the carcinogens released. Research also shows a much lower health risk from burning candles.

A 2020 Navigate360 survey concluded that 70% of Americans only felt safe at home. Yet, our safe places can also be home to hidden and unexpected dangers. So keep reading to discover the potential safety concerns of incense and candles, from fire hazards to possibly toxic fumes.

Disclaimer: The following article does not substitute health and safety advice. It merely presents both sides of the debate using statistics and facts. If you have health or safety concerns about burning either, I encourage you to do additional research.

Fire Hazards

The Zebra—the insurance company, not the species—revealed that Americans dub home fires the #1 worst household emergency. But here’s a not-so-fun fact: home fires actually ranked 12% higher than natural disasters and 18 points higher than break-ins or thefts at 35%.

scented candles and incense sticks side by side

You may know that both incense and scented candles require a lit flame to release their long lasting fragrance. However, which fragrance solution is least likely to be a fire hazard between incense and candles?


Fires from lighting incense are typically not too common. However, that doesn’t mean they can’t happen. In fact, fire crews in the U.K. responded to two incense-related house fires within a few hours in April 2019.

Now, there are generally two ways to burn incense.

Direct-burning (combustible) involves lighting incense sticks or cones to smolder at the tip until it runs out of fragrance. Indirect-burning (non-combustible) does not require a flame and relies on an outside heat source to release its aroma.

Here’s how each of these types lends to a fire risk:

Direct-Burning Incense + Fire Risk

Direct-burning doesn’t require an active lit flame like a candle, which leads many to believe it’s safer than candles.

But is it?

As the incense sticks or cones burns, the ash at the tip will fall to the holder below until there’s nothing left to burn. The fire risk increases if this falling ash misses the incense holder entirely and lands on flammable materials.

burning incense cones vs incense sticks

Overturned incense holders and allowing incense to smolder near a flammable material can also lend to a fire risk. So can leaving lit incense unattended or lighting incense in the path of a breeze or draft that can blow the hot ash elsewhere.

Of course, most (if not all) of these risks are preventable:

  • Don’t light incense near anything flammable, such as curtains or wood.
  • Do not leave incense unattended when lit.
  • Don’t light it in an area with heavy traffic where someone (or something) may knock it over).
  • Don’t allow incense to smolder in front of an air vent or an open window.
  • Use a long, wide, sturdy, and fire-resistant incense holder. 

Indirect-Burning Incense + Fire Risk

Despite its name, “non-combustible” incense isn’t 100% fireproof. That’s because the indirect-burning method involve a separate heating element that warms charcoal. (Oh, and this charcoal can top 1,000 °F or 538 °C.) 

In essence, you’d heat the charcoal or charcoal tablets and then sprinkle the resin (the fragrance) onto the glowing charcoal. Doing so releases the scent. 

With proper use, indirect-burning typically isn’t a fire risk on its own like traditional incense sticks and cones. However, the smoldering charcoal could create a fire risk when lit near something flammable or near a drafty window. 

Take proper precautions—like those in the direct-burning section—for the safest experience. Additionally, don’t throw out anything incense-related until you’re completely sure it’s cooled down and won’t ignite in the garbage can.


a lit scented candle

According to the National Fire Protection Association, candles cause 2% of all house fires. It’s also worth mentioning that carelessness is to blame for many of these fires. 10% resulted from falling asleep, and 60% were from a candle lit near combustible materials.

Of course, the major concern with candles is the open flame when lit. It could take a matter of 30 seconds for an accidentally tipped-over candle to evolve into a major fire.

Although unusual, another fire risk comes from candles that—you know—spontaneously shatter. Mainstays recalled 1.2 million candles in February 2023 for just that.

Sometimes, the candle’s heat will also shatter the glass. The broken glass could cause the hot wax and flame to spill out, potentially igniting nearby combustible objects.

To burn a candle safely and lower the risk of a house fire:

  • Ensure candles have at least 12 inches of space from flammable objects.
  • Lit candles should never be left unattended.
  • Keep lit candles away from pets, children, and heavy foot traffic.
  • Avoid lighting candles in rooms where you sleep.
  • Don’t light candles near open or drafty windows or vents.
  • Trim your candle wick regularly.

Toxic Fumes

We live in a society where26.5 million Americans have asthma. Lung cancer ranks as the #3 most common cancer in the U.S. And, air pollution is only worsening.

Now, here’s the next safety concern: the potentially toxic fumes emitted by lit incense and candles.

scented candles and incense sticks side by side

Both incense and candles release a concoction of potentially harmful chemicals when lit/burned. So how do the two compare when it comes to potential fume toxicity?


As you burn incense, it releases the following substances into the air:

Particulate Matter

Abbreviated as “PM,” particulate matter is extremely small droplets—either liquid or solid—that sit in the air. We breathe these in unknowingly when we burn incense. But you may not know that PM is a form of air pollution and carcinogen.

Unfortunately, one bit of research links high PM exposure to possible lung cancer. One study from 2008 also found that smoldering incense releases more particulates than cigarette smoke (45 mg/g vs. 10).

It’s also worth noting that a lot of the research linking incense to respiratory cancers hinges on one key aspect: regular and prolonged exposure. Therefore, occasional use in a well-ventilated room as long as you ensure proper ventilation.

Volatile Organic Compounds

Volatile organic compounds (or VOCs) are organic and dangerous chemicals released into the air via incense smoke. Burning incense can release everything from formaldehyde to benzine into the room.

Choosing incense dipped in natural (rather than synthetic) oils can reduce VOC dangers. Still, it remains exceeding unlikely that lit incense will ever “purify” the air as many believe.

Carbon Monoxide

Carbon monoxide is an odorless, colorless, and tasteless gas that leads to roughly 420 deaths per year in the U.S. when exposed to high amounts. Scary enough, one study of 23 incense found that the release of carbon monoxide from incense is high enough to cause health issues.

Polycyclic Aromatic Hydrocarbons

Polycyclic aromatic hydrocarbons (or PAHs) are chemicals that come from incomplete combustion. Unfortunately, there’s also a link between PAHs (a known carcinogen) and certain types of cancers, like lung, bladder, and skin cancers.


Candles release these into the air as they burn, which may affect indoor air quality:

Carbon Dioxide + Water Vapor

As candles burn, the chemicals in the air and the wax combine to produce carbon dioxide and water vapor. Candles also emit small amounts of carbon monoxide as they burn, though the amount is so small that it’s unlikely to harm your health.


Soot” is the black smoke that comes from candles. It’s especially common in candles with longer wicks that burn hotter and cannot combust completely. The wax travels to the candle wick quicker than it can burn, creating the black smoke known as soot.

black soot on glass of scented candle

Now, on its own, soot typically isn’t a major health concern without long-term exposure in high concentrations. That said, you can lessen the amount of soot you breathe in by choosing soy candles, which are known to produce less soot than paraffin candles.

You should also keep your candle wick trimmed and allow for ample ventilation in the room.

Volatile Organic Compounds

Like incense, candles also release a blend of VOCs, including benzene and formaldehyde, which are carcinogens. However, studies suggest that the VOC content in lit candles is so low that it’s not a major risk to human health.

Particulate Matter

Like incense, candles emit particulate matter (or PM), particularly after being blown out. Long-term exposure to PM can increase your risk of asthma attacks and other breathing issues, but it’s increasingly rare.

Final Thoughts

To be completely honest, candles and incense aren’t 100% safe concerning fire hazards and fume emissions. There will always be a slight risk, regardless of which one you prefer. However, there are safer ways to use both of these odor-busters. 

First, whether you choose incense or candles, always follow proper safety precautions. 

If you choose candles, choose soot-free ones to reduce the amount of soot released into the air. If you select incense, stick to direct-burning. Buy those dipped in natural oils that can limit the toxic fumes.

And never leave lit incense or candles unattended!