Table 1.

Examples of Patented Innovations to Reduce Smoke Constituents or Quantity of Smoke Emitted by Cigarettes

Site	Strategy and exemplar quotations:
Number of patents identified (n = 62)
Cigarette paper or sheet material	Mechanically trapping particulate: “...the wrapper comprising a ceramic material and being capable of mechanically trapping mainly aqueous particulate phase materials in the sidestream smoke, thereby reducing sidestream smoke deliveries considerably despite the use of the wrapper with conventional tobacco materials.” (Bushby, McAdam, & Timms, 2001)
	Reducing sidestream smoke by increasing burn efficiency by treating paper: “A high surface area oxidative catalyst smoke suppressive composition, smoke suppressive articles, and method of making such compositions and articles are disclosed. The smoke suppressive composition is a solid solution comprising a mixture of iron (Fe) and magnesium (Mg) that promotes efficient combustion, articles treated with such compositions, and methods for making such smoke suppressive compositions and articles… The iron-magnesium composition demonstrates high surface area and efficient combustion for embodiments... The compositions provide superior smoke suppression for items such as cigarettes and smoke suppressive articles. The smoke suppressive compositions are particularly useful for reducing cigarette sidestream smoke in cigarettes.” (Quincy & Cartwright, 1997)
	Material with other components to remove particles, aerosols and convert gases: “..the invention [uses] a treatment material in a process for treating cigarette sidestream smoke to remove visible smoke particles, aerosols and convert gases with off odours. Sheet material for application to a cigarette to reduce sidestream smoke... comprising substantially hydrophobic sorbent, sheet reinforcement and an oxygen storage component which releases oxygen at free-burn rate temperatures adjacent a burning coal of a cigarette....” (Bowen, Becker, Brackmann, & Snaidr, 2004)
Tobacco mix	Addition of carbon particles to reconstituted tobacco: “Use in the tobacco rod of a smoking article of tobacco mixed with a reconstituted tobacco sheet which includes activated carbon particles, surrounded by a paper of... permeability of 20 coresta or greater results in an article having reduced sidestream smoke and selective reduction of certain ingredients in mainstream smoke, whereby the smoker has a perception of increased smoothness.” (Sampson, 1999)
Multi-site	Reduction of carbon dioxide from mainstream smoke (catalyst): “The catalyst comprises nanoscale particles of palladium and/or palladium oxide incorporated in and/or on nanoscale particles of a metal or metal oxide. The nanoscale catalyst, which can be incorporated in the tobacco cut filler, cigarette wrapper and/or cigarette filter of a cigarette, is useful for low-temperature and near-ambient temperature catalysis. The nanoscale catalyst can convert carbon monoxide and nitric oxide that are found in mainstream smoke to carbon dioxide and nitrogen, respectively....” (El-Shall, 2006)
	Reduction of polycyclic aromatic hydrocarbons in mainstream and sidestream smoke (palladium): “An apparatus and method for the process of applying palladium salts to tobacco cut filler and other smokable products so that polycyclic aromatic hydrocarbons can be reduced in both mainstream and sidestream cigarette smoke.” (Zimmerman & Baggett, 2008)