When certain resins or woods are burned, they release a fragrant smoke. This aromatic smoke is called incense. The scent of the incense itself is also sometimes considered incense. Incense may be used for religious or ritual purposes, or simply to add a pleasant fragrance to the air. It may be used for meditation, aromatherapy, or as a way to repel insects. Incense is usually made of a mixture of fuel and oxidizer materials, such as charcoal or wood powders. Fragrance is added either prior to shaping, as in the case of powdered incense materials, or after, as in the case of pressed sticks and cones. The charcoal provides the fuel for combustion while the oxidizer sustains the burning. The aromatic substances are usually mixed with gum arabic and/or makko powder, which help bind the ingredients together. Other common ingredients include natural essential oils, guarana bark (Rhamnus africanus), and agarwood powder (Kodo or Xiang Dao).
The use of incense in religious services goes back a long way. In fact, the Bible mentions frankincense, which comes from the resin of certain trees, among the gifts given to the baby Jesus. In Judaism and other ancient cultures, incense was used for purification, veneration, and forging a connection with the divine.
In Christianity, incense was avoided for a time as a pagan practice related to sacrifice and emperor worship, but it was gradually introduced into the liturgy, especially in Eastern churches. By the fourth century, it was often used at many points during the Eucharist and daily office, and for processions.
Like second hand smoke, the pollutants emitted by incense are harmful to human health. They can include particulate matters, volatile organic compounds such as musk ketones and musk ambrette, aldehydes, polycyclic aromatic hydrocarbons, and diethylphthalate. In addition, they can cause respiratory irritation.
While the burning of incense in the home is a tradition that dates back to ancient Egypt, it is now more commonly found in stores and businesses where it is sold for its fragrance. It is also widely used in religious ceremonies and meditation. Some people just enjoy the scent and don’t assign any other significance to it.
Some of the more unusual uses for incense include its ability to repel mosquitoes, which can be quite bothersome. It is often used in conjunction with a religious ceremony to keep annoying insects away from the devotees. Some Zen Buddhists claim that the incense they burn during their meditative practices is designed to do just this. Other common uses are as a way to perfume a room, to freshen up clothing, or as a means of removing unpleasant odors from a room. It is even sometimes used as a substitute for candles in certain religious celebrations.