It is technically possible to light a cinnamon stick on fire and inhale the resulting smoke, but doing so is highly unsafe. A cinnamon stick is the dried bark of a tree, containing concentrated volatile oils and chemical components not meant for combustion or inhalation. Smoking cinnamon exposes the lungs to a complex mix of respiratory irritants and potentially toxic compounds, ranging from immediate lung irritation to systemic toxicity.
Inhalation Hazards of Burning Plant Material
Smoking cinnamon introduces a basic physical hazard common to the combustion of any plant material. Burning wood or bark generates fine particulate matter, including minute particles of soot and ash classified as PM2.5 (particulate matter less than 2.5 micrometers in diameter). These microscopic particles bypass the body’s natural defenses and travel deep into the lower respiratory tract and the delicate alveolar sacs of the lungs. The physical presence of these particles causes acute inflammation and can lead to chronic respiratory illnesses, such as bronchitis, with repeated exposure.
Incomplete combustion also releases gases like carbon monoxide and complex organic molecules known as polycyclic aromatic hydrocarbons (PAHs). PAHs are a group of compounds that includes known and probable human carcinogens, also found in cigarette and wood smoke.
Volatile Compounds and Respiratory Irritation
Beyond the general hazards of smoke, cinnamon presents unique dangers due to its high concentration of volatile chemical compounds. The characteristic scent and flavor of cinnamon largely come from cinnamaldehyde, which makes up a significant portion of the bark’s essential oil. When burned, this compound is rapidly aerosolized and concentrated in the smoke, becoming a potent respiratory irritant.
Cinnamaldehyde acts on the transient receptor potential A1 (TRPA1) receptors in the airways, leading to an immediate burning sensation, coughing, and irritation of the throat and nasal passages. This chemical irritation impairs the function of the cilia, the tiny hair-like structures responsible for clearing mucus and foreign debris. Disrupting this mucociliary clearance mechanism compromises the lung’s anti-bacterial defense system, increasing the risk of respiratory infection and inflammation.
Coumarin and Systemic Toxicity
A more insidious danger comes from coumarin, a naturally occurring substance found in high concentrations in Cassia cinnamon, the most common variety sold in North America. Coumarin is recognized as a potential hepatotoxin, meaning it can cause liver damage in sensitive individuals or at high doses. While coumarin is regulated in food products, its effects when inhaled are highly concerning.
The lungs offer a direct route into the bloodstream, bypassing the initial filtering of the digestive system. Inhalation of coumarin, likely in an aerosolized or chemically altered form from the heat, introduces the possibility of systemic absorption and subsequent damage to the liver. Studies also indicate coumarin may have carcinogenic properties in animal models, contributing to long-term health risks. The concentration of this compound varies greatly, making combustion an unpredictable and unsafe method of exposure.
Safe Methods for Utilizing Cinnamon Aromas
People seeking the pleasant aroma of cinnamon have multiple safe alternatives that avoid the dangers of combustion. These methods allow enjoyment of the spice’s fragrance by utilizing its natural volatility while eliminating the risks associated with inhaling smoke and chemical irritants.
Safe methods for utilizing cinnamon aromas include:
- Simmering a few cinnamon sticks in a pot of water on the stove to allow the scent to diffuse via steam.
- Using an electric essential oil diffuser with cinnamon oil, which disperses the oil as a fine, cool mist.
- Placing cinnamon sticks in a decorative dish as a natural, passive diffuser.