In 1995 the public exposure of confidential industry documents from within Brown & Williamson Tobacco Corporation, for the first time revealed the extent of deliberate manipulation of nicotine levels in cigarettes by tobacco companies in the USA in order to increase their addictiveness. Tobacco companies dispute this interpretation of the documents. In one document, a 1972 memorandum, tobacco executives describe the cigarette as "a storage container for a daily dose of nicotine", an acknowledgement of the active - and addictive - ingredient of tobacco. Tobacco producers have said that they do add nicotine to cigarettes, but only to maintain levels lost in the processing, while consumer and health groups accuse the tobacco industry of deliberately "spiking" cigarettes with extra nicotine, to enforce addiction.
In 1995 the New York Times presented information on the activities of the Philip Morris company based upon over 2000 pages of research documentation it received from an unidentified source. This documentation showed that Philip Morris had been actively studying different levels of nicotine in cigarettes and their effects upon people over many years and had produced manipulated nicotine levels for test cigarettes. The company denies any of this research was later applied to market products. The information further revealed wide ranging studies on students and young people, which opponents contend has always been the main target group for tobacco manufacturers.