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commonly increased another constituent. In general, efforts to reduce individual 

 constituents have not been successful. 



General Reduction 



During the same period, Reynolds Tobacco and other cigarette manufacturers also 

 directed their research to attempt to reduce levels of all constituents. This approach, also 

 advocated by researchers such as Dr. Ernst Wynder, offered advantages over selective 

 reduction because it led to the reduction of total smoke yields and the levels of individual 

 compounds more or less proportionately. 



To understand the concept of general reduction, it is essential to understand what 

 smoke is. Smoke is a complex mixture -- it consists of a particulate or "tar" phase as well 

 as a vapor or gas phase. Since the mid-1950s, cigarette manufacturers have devoted 

 extensive resources to achieve a general reduction in "tar" and the vapor phase components 

 of cigarette smoke. Techniques incorporated in cigarettes over the last 40 years which 

 reduce "tar" include: 



• Filtration 



• Reconstituted tobacco 



• Paper porosity 



• Reduced tobacco 



• Expanded tobacco 



• Filter ventilation 



Design changes such as the development of more porous cigarette paper, improved 

 filtration, and the use of expanded (or "puffed") tobacco and reconstituted tobacco made 



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