The practice of burning incense carries severe environmental and health risks. Research has shown that IS inhalation can increase the risk of various diseases, including cancer, asthma and heart problems, by aggravated oxidative stress.
Quantitative IS profiling studies indicate that particulate matter emitted by incense burning deteriorates air quality upon release, with carcinogenicity and genotoxicity. It also triggers inflammatory reactions such as allergic contact dermatitis.
Respiratory Issues
Burning incense releases particulate matter and gaseous chemicals into the air. These pollutants can cause a wide variety of health issues. Particulate matter can irritate the eyes and lungs, and can contribute to cardiovascular disease. Many of the gases emitted by incense smoke are known to be carcinogenic, including polycyclic aromatic hydrocarbons.
The volatile organic compounds emitted by incense smoke can also irritate the eyes, nose and throat. Aldehydes such as acetaldehyde and formaldehyde can irritate the skin and lungs, and are suspected to aggravate asthma and allergies.
One study found that children who used incense at home had a higher risk of leukemia than other children, even after controlling for smoking and other factors. However, further investigation is required to understand this finding. Other studies have linked household incense use to hypertension and other respiratory problems. In addition, incense smoke can trigger inflammation in the lungs and gastrointestinal tract. These compounds can also slow metabolism, leading to unwanted weight gain and poor cholesterol levels.
Cardiovascular Issues
Inhaling the complex mixture of gases and particulates produced by burning incense can cause a variety of adverse health effects. This includes asthma and asthma-like symptoms, respiratory dysfunction, cardiovascular disease and cancer, as well as inflammatory reactions in the body.
Researchers have also found that incense smoke contains a number of toxic substances. These include irritants such as polycyclic aromatic hydrocarbons, volatile organic compounds and metals; carcinogens, including N-nitroso compounds, and N-nitrosamines; and oxidants, including reactive oxygen species and nitric oxide.
In addition, incense smoke can be problematic for children. One study found that children exposed to household incense burning had higher rates of bronchitis and bronchiolitis than those not exposed. However, the sample size was small and the lead researcher worked for a tobacco company. This may have introduced a degree of bias into the results. Another study found that exposure to incense smoke is associated with delay in infant gross motor development. The researchers believe that this is due to the inflammatory properties of incense smoke and its ability to increase the activity of certain enzymes.
Neuropsychological Issues
Inhalation of incense smoke may cause irritation to the nose, throat, and eyes. The volatile organic compounds in the smoke such as aldehydes may produce irritant reactions by stimulating the nervous system and causing inflammation.
Another risk is that the vapors may contain nephrotoxic chemicals such as N-nitroso compounds. These can lead to nephrotoxicity by disrupting the renal tubules. In one study, exposure to incense and cigarette smoke was associated with decreased kidney function in participants. The researchers speculated that it might be due to the higher nitrosamine levels in the incense smoke.
A possible mechanism involves oxidative stress-related aberrant inflammation and irreversible DNA damage. This is supported by several epidemiological studies of incense use and adverse cardiovascular health outcomes. In addition, neuroimaging results have shown that incense burning is associated with poor cognitive performance over 3 years and lower brain connectivity in the DMN. Incense burning also interacts with vascular disease and other covariates to predispose to worse cognitive functioning.
Dermatological Issues
The particulate matter in incense smoke contains carcinogens and irritants that can contribute to a variety of respiratory problems. These can include chronic cough, sputum production, runny nose and wheezing. The smoke can also lead to lung inflammation and cancer.
Studies have found that burning incense emits polycyclic aromatic hydrocarbons (PAHs) into the air. These compounds are known to cause several types of cancers in humans. The toxicity of PAHs depends on the length and frequency of exposure, but even short-term exposure can cause damage.
Incense use has been linked to cardiovascular-caused deaths as well, possibly because the toxins in the smoke can negatively affect metabolism. Some studies have shown that incense can also be dangerous to pets, especially those with short snouts like pugs and bulldogs. In addition, incense use can be harmful to children. In one study, long-term exposure to incense smoke led to poor cognitive development and lower IQ scores in children.