Cigarette filter ventilation is a defective design because of misleading taste, bigger puffs, and blocked vents.
OBJECTIVE
To review tobacco industry documents on filter ventilation in light of published studies and to explore the role of filter ventilation in the design of cigarettes that deliver higher smoke yields to smokers than would be expected from standard machine smoked tests (Federal Trade Commission (FTC), International Organization for Standardization (ISO)).


METHODS
Searched from November 1999 to November 2000 internet databases of industry documents (www.pmdocs.com, www.rjrtdocs.com, www.lorillarddocs.com, www.bw.aalatg.com, www.cdc.gov/tobacco/industrydocs, www.tobaccodocuments.org, www.tobaccopapers.org, www.hlth.gov.bc.ca/Guildford, www.cctc.ca/ncth/Guildford, www.cctc.ca/ncth/Guildford2) for documents related to filter ventilation. Documents found dated from 1955 through 1994.


METHODS
Those documents judged to contain the most relevant information or data on filter ventilation related to cigarette taste and compensatory smoking, while also trying to avoid redundancy from various documents deriving from the same underlying data.


RESULTS
Filter ventilation is a crucial design feature creating three main problems for lower tar cigarettes as measured by official smoking machine testing. Firstly, it misleadingly makes cigarettes taste lighter and milder, and, therefore, they appear less dangerous to smokers. Secondly, it promotes compensation mainly by facilitating the taking of larger puffs. Thirdly, for very heavily ventilated cigarettes (that is, > 65% filter air dilution), behavioural blocking of vents with lips or fingers is an additional contributor to compensatory smoking. These three effects are found in industry research as well as published research.


CONCLUSIONS
Filter ventilation is a dangerous, defective technology that should be abandoned in less hazardous nicotine delivery systems. Health interested groups should test cigarettes in a way that reflects compensatory smoking. Lower tar (vented filter) cigarettes should be actively countermarketed.
Kozlowski
L T
LT
Department of Biobehavioral Health, The Pennsylvania State University, Pennsylvania 16802, USA. ltk1@psu.edu
O'Connor
R J
RJ
D002248:Carbon Monoxide / Q000032:analysis; D003257:Consumer Product Safety; D004867:Equipment Design; D005374:Filtration / Q000295:instrumentation*; D006801:Humans; D009538:Nicotine / Q000032:analysis; D012907:Smoking / Q000009:adverse effects; D013638:Tars / Q000032:analysis; D013672:Technology; D019460:Tobacco Industry / Q000379:methods
D013638:Tars; D009538:Nicotine; D002248:Carbon Monoxide