Incense - Incense and Health

Incense and Health

Incense smoke contains various contaminants including gaseous pollutants, such as carbon monoxide (CO), nitrogen oxides (NO_x), sulfur oxides (SO_x), volatile organic compounds (VOCs), and absorbed toxic pollutants (polycyclic aromatic hydrocarbons and toxic metals). The solid particles range between ~10 and 500 nm. The emission rate decreases in the row Indian sandalwood > Japanese aloeswood > Taiwanese aloeswood > smokeless sandalwood.

Research carried out in Taiwan in 2001 linked the burning of incense sticks to the slow accumulation of potential carcinogens in a poorly ventilated environment by measuring the levels of polycyclic aromatic hydrocarbons (including benzopyrene) within Buddhist temples. The study found gaseous aliphatic aldehydes, which are carcinogenic and mutagenic, in incense smoke.

A survey of risk factors for lung cancer, also conducted in Taiwan, noted an inverse association between incense burning and adenocarcinoma of the lung, though the finding was not deemed significant.

In contrast, a study by several Asian Cancer Research Centers showed: "No association was found between exposure to incense burning and respiratory symptoms like chronic cough, chronic sputum, chronic bronchitis, runny nose, wheezing, asthma, allergic rhinitis, or pneumonia among the three populations studied: i.e. primary school children, their non-smoking mothers, or a group of older non-smoking female controls. Incense burning did not affect lung cancer risk among non-smokers, but it significantly reduced risk among smokers, even after adjusting for lifetime smoking amount." However, the researchers qualified the findings by noting that incense burning in the studied population was associated with certain low-cancer-risk dietary habits, and concluded that "diet can be a significant confounder of epidemiological studies on air pollution and respiratory health."

Frankincense has been shown to cause antidepressive behavior in mice. It activated the poorly understood ion channels in the brain to alleviate anxiety and depression.