environment within the human body, so they can thrive within this elevated pH environment. This makes the skin more than usually susceptible to bacterial colonization. Bacteria on the skin feed on the waste proteins and fatty acids in the sweat from the apocrine glands and on dead skin and hair cells, releasing trans-3-methyl-2-hexenoic acid in their waste, which is the primary cause of body odor. Underarm hair wicks the moisture away from the skin and aids in keeping the skin dry enough to prevent or diminish bacterial colonization. The hair is less susceptible to bacterial growth and therefore reduces bacterial odor. The apocrine sweat glands are inactive until puberty, which is why body odor often only becomes noticeable at that time. Deodorant products work in one of two ways – by preventing sweat from occurring, or by allowing it to occur but preventing bacterial activity that decomposes sweat on the skin. History Modern deodorants In 1888, the first modern commercial deodorant, Mum, was developed and patented by a U.S. inventor in Philadelphia, Pennsylvania, Edna Murphey. The small company was bought by Bristol-Myers in 1931 and in the late 1940s, Helen Barnett Diserens developed an underarm applicator based on the newly invented ball-point pen. In 1952, the company began marketing the product under the name Ban Roll-On. The product was briefly withdrawn from the market in the U.S., but it is once again available at retailers in the U.S. under the brand Ban. In the UK it is sold under the names Mum Solid and Mum Pump Spray. Chattem acquired Ban deodorant brand in 1998 and subsequently sold it to Kao Corporation in 2000. In 1903, the first commercial antiperspirant was Everdry. The modern formulation of the antiperspirant was patented by Jules Montenier on January 28, 1941. This patent addressed the problem of the excessive acidity of aluminum chloride and its excessive irritation of the skin, by combining it with a soluble nitrile or a similar compound. This formulation was first found in "Stopette" deodorant spray, which Time Magazine called "the best-selling deodorant of the early 1950s". "Stopette" gained its prominence as the first and long-time sponsor of the game show What's My Line?, and was later eclipsed by many other brands as the 1941 patent expired. Between 1942 and 1957, the market for deodorants increased 600 times to become a $70 million market. Deodorants were originally marketed primarily to women,