Though modern society uses incense to make rooms smell nice, burning incense has a long history of cultural and spiritual meaning. People worldwide burn incense for prayer, meditation, healing, community ceremonies, celebration and in honor of loved ones who have passed. But burning anything indoors shouldn’t be done without considering the serious risk to lung health. Incense smoke is no exception, as it has been found to contain many dangerous particles and chemicals that can irritate and damage the lungs.
What is in incense smoke?
When incense burns, it releases high levels of particulate matter and toxic gases. “Most incense sticks are made of composite material including fragrance, wood chips, coal (or potassium nitrate), and some type of adhesive material to keep it all together. When this is burned it generates gaseous pollutants that worsen indoor air quality,” explains Dr. Brian Christman, Professor of Medicine at Vanderbilt University. Specifically, studies have identified carbon monoxide, nitrogen oxide, sulfur dioxide, formaldehyde, and chemicals called polycyclic aromatic hydrocarbons (PAHs). Many of these chemicals are carcinogens that can also be found in cigarette smoke.
Further research has shown that burning just one gram of incense can create about 45 milligrams of particulate matter, which is four times more than a cigarette produces. Particulate matter (PM2.5) are particles that are so tiny they can travel deep into the lungs, irritating, inflaming and damaging the airways.
How does incense affect the lungs?
All these chemicals contained in incense smoke can cause health issues including headaches, skin allergies and a range of lung health problems. “Short term, the gaseous compounds such as sulfur dioxide and nitrogen dioxide dissolve in the layer that lines the airways and generates irritation and inflammation,” Dr. Christman explained. This irritation leads to common respiratory symptoms including coughing, wheezing, sore throat, shortness of breath, chest tightness and asthma flare-ups. This inflammation of the airways can also make it harder for the body to clear out germs, resulting in more frequent and severe lung infections.
Dr. Christman warns that studies have also shown that long-term exposure to incense smoke can lower lung function and increase the risk of chronic breathing diseases. “In one study from Taiwan, daily exposure of children to burning incense resulted in reduced lung function as measured by pulmonary function testing,” he said.
Who’s at risk of lung damage from incense burning?
Since incense is typically burned indoors, the chemicals in the smoke can build up and remain in the air. If there is poor ventilation, this could mean exposing family members and pets to secondhand smoke. “Anyone in the environment would be exposed to ambient smoke with gaseous pollutants and small particle irritants,” Dr. Christman continued.
Additionally, incense can leave behind thirdhand smoke, or toxic particles that cling to furniture, carpets, fabrics and walls. “With sufficient daily exposure, clothing and curtains positioned near burning incense would absorb many chemicals and particles that could be problematic,” he said. “And young children, with their preference for exploring the world by putting objects in their mouth, would be at high risk.”
Children are one of the high-risk groups for other reasons as well. Their small airways are more vulnerable to air pollution caused by any kind of smoke. One study found that children living where incense was burned often had more coughing, wheezing and lung infections. This is because kids’ smaller, still growing bodies mean they breathe faster and take in more polluted air in every breath than adults. Breathing in polluted air can slow lung growth and cause long-term lung damage that can last well into adulthood and even lead to chronic lung disease.
But people with underlying lung or heart conditions are considered at the highest risk. People with conditions like COPD or asthma already manage more inflamed airways and are more likely to experience negative effects from triggers like incense smoke. Other high-risk groups would include individuals with congestive heart failure, lung cancer, pneumonia, allergic rhinitis or interstitial lung disease.
The American College of Allergy, Asthma, and Immunology has found that incense can trigger asthma attacks because the smoke irritates the already sensitive airways and causes them to tighten. Even brief exposure can cause coughing and wheezing, and exposure over a longer period of time may result in permanent lung damage.
What are safer alternatives?
No indoor burning is completely safe as it adds pollution to the air and increases health risks. However, the cultural and spiritual importance of incense must be respected. “The key is to reduce the duration and frequency of exposure and improve ventilation in the area,” Dr. Christman said. “Opening a window and burning the incense near the window can be helpful and will reduce exposure to the occupants of the home.”
Other considerations are to use fans and portable HEPA air cleaners or only burning incense outdoors. If someone in the home has an existing lung condition, you may want to consider only using incense for cultural and spiritual practices when they aren't home. If they are home, try to limit their exposure. If you choose to burn incense, you can also minimize the health risks by choosing high-quality, plant-based incense over synthetic varieties. Essential oils should be avoided, as they come with health risks.
For more information on how to protect your lung health from indoor air pollutants, visit lung.org/clean-air.
Blog last updated: June 5, 2026
