Are scented candles dangerous? What you need to know
Scented candles can create a pleasant atmosphere, but when they burn, they also generate combustion products and can temporarily increase the concentration of particles and volatile organic compounds in the indoor air. Therefore, rather than labeling all candles as "toxic," it is better to understand what happens when they burn and how to use them responsibly.
Do scented candles pollute the air?
Yes, a lit candle is a small source of combustion. Studies have detected particles and various gaseous compounds during candle combustion, including volatile organic compounds and common combustion byproducts. The amount emitted depends on the type of candle, the formulation, the wick, the duration of use, and ventilation conditions.
Indoor research has observed increases in particles and volatile compounds during the use of scented candles. This does not mean that an occasionally used candle will cause illness, but it does mean that ventilation is a simple measure to reduce the accumulation of pollutants in the environment.
What substances can they emit?
When burned, candles can emit particles and compounds such as formaldehyde, benzene, carbon monoxide, nitrogen oxides, and other organic compounds, as well as substances from the fragrances. The amount varies greatly between products and combustion conditions.
That is why it is not correct to claim that all scented candles contain the same substances or that a certain wax is automatically "safe" or "toxic." The formulation, combustion quality, and usage are relevant factors.
Is paraffin dangerous?
Paraffin is a petroleum-derived wax that is widely used in candle making. Its origin alone does not mean a candle is harmful to health. What matters is considering the actual emissions during combustion, the product's formulation, and the conditions of use.
There are also candles made with other waxes, such as soy, rapeseed, beeswax, or other blends. Choosing a different wax may be part of your material preferences, but it should not be interpreted as an absolute guarantee that there will be no emissions when lit: any combustion produces substances.
What happens if a candle produces black smoke?
A flame that produces too much soot may indicate poor combustion. It can be related to a wick that is too long, drafts, buildup of debris, or certain characteristics of the candle.
If black smoke appears, extinguish the candle, let it cool, and trim the wick following the manufacturer's instructions before using it again. Avoid placing it near drafts.
How to use scented candles more safely
- Ventilate the room. Especially if the room is small or remains closed for a long time.
- Do not leave it unattended while lit. A lit candle is an open flame and there is a fire risk.
- Keep it away from flammable materials such as curtains, textiles, paper, or decorative items that could get hot.
- Place it on a stable and heat-resistant surface.
- Avoid burning it for prolonged periods. Always follow the manufacturer's specific instructions.
- Extinguish it if the flame becomes unstable, too high, or generates excessive smoke.
- Do not use a candle in an unventilated room for long periods.
Is a natural candle better?
"Natural" does not automatically mean free of emissions or guarantee that a candle is harmless when burned. If you are looking for an option with a formulation you feel more comfortable with, you can check the type of wax, the fragrance, the wick, and the information provided by the manufacturer.
The most important thing is to combine an informed choice with moderate use and good ventilation.
Scented candles and sensitive individuals
If a person notices irritation, headaches, coughing, or respiratory discomfort when using a candle, the prudent thing to do is extinguish it, ventilate the room, and avoid using it if the discomfort recurs. People with diagnosed respiratory conditions should follow the recommendations of their healthcare professionals.
Frequently asked questions about scented candles
Are scented candles toxic?
It cannot be claimed that all scented candles are toxic. When they burn, they can emit particles and volatile compounds, but emissions and exposure depend on the product and usage conditions.
Is it bad to sleep with a candle lit?
A lit candle should not be left unattended while sleeping. In addition to the air quality issue, there is an obvious risk of fire.
Should you ventilate after lighting a candle?
Ventilating helps renew indoor air and reduce the concentration of pollutants that may have accumulated during combustion.
Do soy candles not pollute?
It is not correct to say that a soy candle does not emit pollutants. When burned, any candle generates combustion products. The type of wax is just one of the influencing factors.
In summary
Scented candles should not be automatically considered "dangerous" or "toxic," but their combustion can introduce particles and compounds into the indoor air. To use them responsibly, opt for products with clear information, avoid burning them for too long, watch the flame, and ventilate the room.
