Table 1

Chronology of events related to the marketing of cigarettes filters in the USA, and filter fibre and carbon particle “fall-out” assays of Phillip Morris, Inc

DateMilestones and documents
1860From 1860 to 1920, cigarette filters were used to keep tobacco particles from entering the mouth1, 2, 7, 8
1863Cigarette filters introduced with charcoal powder, cotton wool, flax, hemp, cloth or course paper1, 6, 7
1917Cigarette filters produced with crepe paper7
1924Cigarette filters made by combining crepe paper and cellulose wadding7
1931Parliament cigarettes (Benson & Hedges)—first major filter tip cigarettes in USA6, 7
1936Viceroy cigarettes (Brown and Williamson)—the first filter cigarette at a popular price. Filter was of treated crepe paper6, 7
1949“Golden Throat” filter introduced by Rothmans, Int—cotton wool with crepe paper7
1950 Until the 1950s, “tipped (filter) cigarettes were felt to be a novelty item directly mainly at the women's market”2
1950Cigarettes with cellulose acetate filters introduced (1% market share); non-filter cigarettes (99% market share)2, 3, 7
1950Viceroy became the first serious brand to feature a filter made from cellulose acetate (“20,000 tiny filter traps”). By 1953, Viceroy was marketed as both regular and king size. The therapeutic qualities of the filter were hinted at in their advertisements6, 7
1952Kent “Micronite” cigarettes were introduced by Lorillard. Filter contained harmful crocidolite asbestos fibres.5, 6, 104 Filter with asbestos fibres removed from the market in 1954
1954Marlboro cigarettes with cork tipped “Selectrate” filter introduced by Philip Morris, Inc7
1954Parliament cigarettes with recessed filter introduced by Philip Morris, Inc6, 7, 22
1954Winston cigarettes marketed by R J Reynolds were the first big selling brand cigarette with a cellulose acetate filter6, 7
1956Kent cigarettes introduced by Lorillard with “Micronite” filter having “high filtration” cellulose acetate (Estron)6, 7
1956Cellulose acetate filaments made by Tennessee Eastman and Celanese companies treated with plasticisers7, 21
1957Human health risks associated with the inhalation of cellulose acetate filter fibres discussed by the president of Phillip Morris, Inc and by officers of other US and European companies21
1958Cellulose acetate fibres released from all filter cigarettes tested: Tareyton, Winston, Kent, L&M, Marlboro, and Viceroy. Charcoal granules were discharged from the filter of Lark cigarettes. Study was funded by the Brown and Williamson Tobacco Co.106
1959Food and Drug Research Laboratories report results to studies contracted by Phillip Morris, Inc to examine “five leading brands [Kent L&M, Marlboro, Salem and Winston] of filter tipped cigarettes for the purpose of evaluating, qualitatively, the relative amounts of this particulate material which could be aspirated from the filters under conditions simulating normal smoking.”107, 108
1959Parliament cigarettes with recessed filter designed to prevent “filter feedback”10, 6, 7, 22
1961“Filter fiber fall-out” studies initiated to count and size cellulose acetate fibres released during smoking (Phillip Morris, Inc24)
1961“Carbon particle fall-out” studies initiated to count charcoal granules released from cigarettes with charcoal filters (Philip Morris, Inc26, 80).
1962“All cigarette filters can be shown to transmit particles to the smoker. The [human lung] free passageways are a thousand times, yea ten thousand times, larger than particles which may pass through them. This goes for carbon, tobacco, sand, clay, lint [fibres, threads, cotton, cellulose] and all similar impurities.” Memo to Mr Hugh Cullman (CEO, Philip Morris, Inc) from H Wakeham (director of research, Philip Morris, Inc)115
1962Philip Morris, Inc reports results of cellulose acetate filter fibre “fall-out” tests that compared their leading brand cigarette (Marlboro) versus their competitor's leading cigarette (L&M)24
1964Surgeon General's report concludes that smoking causes lung cancer of men. Filter business becomes a health issue. Sales of filtered cigarettes increase remarkably2, 3, 6, 11
1969Carbon particles are released from Lark cigarettes with charcoal filters reported in “fall-out” studies of Phillip Morris, Inc28, 31, 100, 101, 106, 114
1973Marlboro becomes the No. 1 cigarette brand worldwide6, 7
1980Almost all cigarettes sold have filters (93% market share; non-filter cigarettes, 7% market share)2, 3, 6
1983Cellulose acetate fibre and carbon granule “fall-out” studies of Philip Morris, Inc—of the documents available, the largest number for any one year were those of 198355–68
1985Revised protocols for filter fibre fall-out (Method S-42) and carbon particle fall-out (method S-43) written by Philip Morris, Inc79, 80
1987The largest number of US patents (n = 36) awarded for cigarette filters in any given year was in 1987
1992Health risks associated with the inhalation of tar coated cigarette filter fibres are discussed for the first time in the popular press (Greensboro News and Record110)
1993Cellulose acetate fibres and particles released from cigarette filters is reported97
1993Cigarette filter fibres identified in the lungs of patients with cancer is reported111
1993R J Reynolds denies that cellulose acetate filter fibres are present in mainstream cigarette smoke94, 95, 96, 116
1994Phillip Morris, Inc. submits order for active record disposal to Nancy Ryan, a technician performing cigarette filter fibre and carbon particle “fall-out” assays90
1995Cellulose acetate fibres and particles released from the filters of popular US brand cigarettes is substantiated in studies using different standardised testing methods was reported by Pauly and co-workers; the question of harm is raised again98
1995The filter of Kent Micronite cigarettes (Lorillard) are shown to release thousands of asbestos fibres and particles during normal smoking conditions. The questions of harm is posed6, 104
1995Smokers (Tijerina et al) file suit against Philip Morris and Hoechst Celanese; defective product (cigarette) litigation18
1995Reemtsma, Inc reports that the observed filter fragments that exist on filter tip are not released into the smoke stream117
1995Social Science Research Council envisaged projects and defines costs to address findings of Pauly and co-workers118
1997Studies of human smokers show that charcoal granules are released from the charcoal filters of Lark cigarettes100, 101
1997US patent No. 5,645,087 awarded to Hauni AG for “decontaminating” cigarette filters13
1998State of Minnesota v. Philip Morris et al. Tobacco Companies required to surrender documents; Philip Morris releases some memos describing “fall-out” studies16, 17
1998Inhaled cellulosic and plastic fibres found in human lungs119
1998Filters of novel cigarette appearing nicotine delivery devices are shown to be contaminated with glass fibres and particles (Premier, Eclipse and NEW Eclipse)102
1998US patent No. 5,738,115 awarded to Hauni AG for “decontaminating” cigarette filters14
1998Borowicz and colleagues report results of tests in which cellulose acetate filter fibres and particles are recovered from mouth washes of all smokers and for all cigarettes tested99
1998Filtrona International Ltd reports the results of studies of fibre fragments from six different cigarette filter types released in tap tests; however, very few fibres found in sham smoking120
1999Philip Morris, Inc reports the release of cellulose acetate filter fibres in “fall-out” studies performed using a revised testing protocol88
1999Most recent filter fibre “fall-out” report available from Philip Morris, Inc88
1999Eastman Chemical Co and others report the results of studies characterising cellulose acetate fibres released from the filter end of cigarettes121, 122
2000Fibres, particles, and other filter elements discharged from the filter into mainstream smoke identified as the “third phase” of cigarette smoke105
2000Survey documents that most all smokers (>95%) perceive that inhalation and/or ingestion of cellulose acetate filter fibres is an additional risk to that known to be associated with cigarette smoking and that tobacco companies have an obligation to inform smokers of this defect. Smokers believe that tobacco companies should advise smokers of filter defects93