Air fresheners are consumer products that mitigate unpleasant odors in indoor spaces. They can be in the form of candles, aerosol sprays, diffusers, potpourri, gels and mechanical or heat release products. Global retail sales of air care products were valued at more than $6 billion in 2006 and are forecast to reach $7.3 billion by 2010. Air fresheners work in one of five ways: Adsorption: Adsorbents like zeolite, activated charcoal or silica gel may be used to eliminate offending, chemical odors. Anesthetization: Some air fresheners employ anesthetics to dull the sense of smell. Chemical neutralization: Substances such as rubber or TEG may be used to neutralize odors. Disinfection: Odors caused by bacterial activity can be eliminated by disinfectants like ozone, TEG, or bleaching agents containing hydrogen peroxide, chlorine or hypochlorites. Masking: Many air fresheners obscure odors with a fragrance.