Fragrance is a combination of chemicals that gives perfume and cologne its distinct scent. Companies that manufacture perfume or cologne buy fragrance mixtures from fragrance houses, which specialize in developing fragrance chemicals. A small number of these chemicals are natural, while the majority are synthetic. The International Fragrance Association (IFRA) lists 3,059 ingredients in a wide variety of combinations. These chemicals may cause allergies and sensitivities. They can also be associated with reproductive and developmental toxicity, cancer, and other health problems. While federal laws require perfume manufacturers to list the ingredients on their products, they do not disclose individual fragrance chemicals in order to protect perfume trade secrets and to maintain confidentiality agreements with their suppliers. As a result, the public is unaware of most fragrance chemicals and their potential effects on health.
Historically, perfumers used raw materials from roots, bark, flowers and other parts of plants that came from many regions of the world. They also used animal products, such as whale and civet cat oil. Today, the majority of perfumes and cologne contain chemical ingredients derived from petroleum, with some having as few as one or as many as 20 ingredients. Perfumes are classified by concentration level, scent family, and note composition. Perfume concentration levels include parfum, eau de parfum, eau de toilette, and eau de cologne. The higher the concentration of a perfume, the stronger its scent and the longer it lasts on the skin.
A fragrance composition consists of three components that unfold over time: the top note, which is the first smell to emerge; the heart note, which is perceived just after the top note evaporates; and the base note, which is emitted for several hours after application. Notes are arranged in categories by scent families and subtypes, with traditional classification terms that have been in use since 1900. The most common scent families are Floral, Chypre, Fougere, Marine/Ozonic, Oriental, and Citrus [1,2].
Research on the psychological impact of fragrance has been limited to anecdotal evidence and experiments that examine hedonic perceptions of perfume and its relation to mood and personality. Studies of the reward system of the limbic brain, however, suggest that hedonically positive odors like perfume activate dopamine neurotransmitter transmission at the orbitofrontal cortex and amygdala.
In addition to the euphoric effect of perfume, some people perceive it as a form of self-expression and social status symbol. For example, some women feel that a specific fragrance indicates an elegant personality, while others believe that it is a way to attract romantic partners. Other reasons for perfume usage are based on religious, cultural, and social beliefs. Perfume is a multibillion-dollar industry and its sales are increasing. It has become a part of the fashion culture, where it is worn as an accessory. In fact, the word “perfume” derives from the Persian term for flower (“ras al-bini”). The earliest references to perfume date back to 5000 BC. By the eighteenth century, a perfumed person was considered fashionable and refined. It was believed that the higher one’s class, the more expensive and sophisticated his or her perfume. Jacques Guerlain, for example, designed perfumes for the upper classes that were scented with fecal and anal smells.