The burning of candles and incense is common in religious ceremonies
worldwide. Analysis of incense smoke has shown the presence of particulate
matter, volatile organic compounds, aldehydes and polycyclic aromatic
hydrocarbons that are hazardous to health. Long-term exposure to smoke
formed during combustion can cause airway dysfunction, allergic reactions
and dermatological effects and is a risk factor implicated in the
development of other serious diseases. In this paper the effect of these
studies are reviewed and simple precautions suggested to avoid toxic effects
of incense smoke.