Basic Principles of Cigarette Design and Function Ken Podraza Ph.D
Basic Principles of Cigarette Design and Function Ken Podraza Ph.D. Director Product Integrity Philip Morris USA
PM USA Presentation to LSRO 10/29-30/01 Cigarette Construction
Tipping Paper Adhesive Seam Inner Adhesive Line
Plug Wrap
Perforated Zone (Ventilation)
Filter Plug
Tobacco Column
Cigarette Wrapper
PM USA Presentation to LSRO 10/29-30/01 Processes Related to Cigarette Construction
rod porosity filter ventilation cone Mainstream Smoke
diffusion filtration smoke generation
PM USA Presentation to LSRO 10/29-30/01 Processes of Smoke Formation
Mainstream Smoke
Combustion Pyrolysis Distillation Pyrosynthesis
PM USA Presentation to LSRO 10/29-30/01 Mainstream Smoke
Filter Mainstream Smoke Tobacco, Ingredients
PM USA Presentation to LSRO 10/29-30/01 Mainstream Smoke Phases
• Particulate Phase – The phase of the cigarette smoke retained on a Cambridge filter pad during machine smoking • Consists of condensed droplets of material ranging in size from 0.2 - 0.4 microns • Gas/Vapor Phase – The phase of the cigarette smoke that passes through a Cambridge filter pad during machine smoking • Consists of permanent gases and volatilized compounds • Cambridge Filter Pad – Consists of a fiberglass sheet that collects greater than 99% of the 0.1 µm diameter particles
PM USA Presentation to LSRO 10/29-30/01 Mainstream Smoke Generated by Smoking Machines
• Smoking Parameters – Federal Trade Commission (FTC) / International Organization for Standardization (ISO) • 35 mL Puff Volume • 2 Second Puff Duration • 60 Second Puff Interval PM USA Presentation to LSRO 10/29-30/01 Mainstream Smoke Measurements
• Traditionally, used to determine “tar”, nicotine and carbon monoxide yields – “Tar” is the weight of the material collected on a Cambridge filter pad when a cigarette is smoked under a defined set of conditions (e.g. ISO or FTC) minus nicotine and water. • Interlaboratory validated methods to measure “tar”, nicotine and carbon monoxide exist
PM USA Presentation to LSRO 10/29-30/01 Smoke Profile • Approximately 4,000 identified constituents in smoke • Difficult to identify an ingredient added to tobacco in the ppm concentration range
FID1 A, (000118\002F0201.D) counts
45000 Particulate Phase of 1R4F
40000
35000
30000
25000
20000
15000
10000
5000
PM USA 20 30 40 50 60 70 Presentation80 to LSRO90 10/29-30/01 min Other Smoke Constituents Measured in Benchmark Studies
• Ammonia & Aromatic • Aromatic • Phenols Amines Hydrocarbons – Phenol – Ammonia –Benzene – Catechol – 1-Aminonaphthalene – Toluene – Resorcinol – 2-Aminonaphthalene –Styrene – Hydroquinone – 3-Aminobiphenyl • Gases –Cresols – 4-Aminobiphenyl – Carbon Monoxide • Tobacco Specific • Aldehydes and Ketones – Hydrogen Cyanide Nitrosamines – Formaldehyde – Nitric Oxide – NAB – Acetaldehyde • Heterocycles – NAT – Propionaldehyde – Pyridine – NNK – Butyraldehyde – Quinoline – NNN – Acrolein • Metals • Unsaturated – Crotonaldehyde –Arsenic Compounds – Acetone –Cadmium – Acrylonitrile – Methyl Ethyl Ketone – Chromium – 1,3-Butadiene • Miscellaneous –Lead – Isoprene –“Tar” – Mercury • Polycyclic Aromatic –Nickel Hydrocarbon – Benzo(a)pyrene PM USA – Selenium Presentation to LSRO 10/29-30/01 Alternate Smoking Parameters
• Massachusetts – 45 mL Puff Volume – 2 Second Puff Duration – 30 Second Puff Interval – 50% Ventilation Holes Blocked • Canadian (Extreme) – 55 mL Puff Volume – 2 Second Puff Duration – 30 Second Puff – 100% Ventilation Holes Blocked
PM USA Presentation to LSRO 10/29-30/01 Constituent Yield Methodology
• Interlaboratory validated methods do not exist
PM USA Presentation to LSRO 10/29-30/01 Machine Cigarette Smoking Compared to Consumer Smoking
• Machine smoking – Standardized method (e.g. FTC, ISO) useful to assure consistency in manufacturing and inter-brand comparison for “tar”, nicotine and carbon monoxide
• Consumer smoking – Actual exposure to smokers is not measured by a smoking machine
PM USA Presentation to LSRO 10/29-30/01 Variability
• All measurements show some variability in their results • There are a number of sources contributing to this variability including: – the method itself – inherent product variability – the sampling procedure
PM USA Presentation to LSRO 10/29-30/01 Mainstream Smoke Summary
• Smoking machine derived mainstream smoke • Actual exposure to smokers is not measured by a smoking machine • Ingredients added to tobacco and part of smoke are not typically measured due to the analytical difficulty – Complex smoke matrix – Low concentration of ingredients used
PM USA Presentation to LSRO 10/29-30/01 Processes of Smoke Formation
Mainstream Smoke
Combustion Pyrolysis Distillation Pyrosynthesis
PM USA Presentation to LSRO 10/29-30/01 The Burning Cigarette
PM USA Reference: The Design of Cigarettes, C. L. Brown Presentation to LSRO 10/29-30/01 Smoke Formation Temperature Profile
Temperature Profile
900 800 700 600 500 400 300 200 100 0 010203040506070
Distance from Coal (mm)
PM USA Presentation to LSRO 10/29-30/01 Distillation Process • Transfer of a compound into the smoke stream unchanged • Analytical Pyrolysis of Menthol
A b u nda nc e
T IC : P 0107 25A .D 4 60 00000
50 00000
40 00000 1 30 00000
20 00000
10 00000 2 3 0 5.00 10 .0 0 15 .0 0 20 .0 0 25 .0 0 30 .0 0 35 .0 0 40 .0 0 45 .0 0 Ti m e - - >
PM USA Presentation to LSRO 10/29-30/01 Combustion Process • Transformation of a compound into one or more other substances by heat in the presence of oxygen
– Formation of CO2, CO, H2O and degradation fragments • Analytical pyrolysis of Cocoa
A b un dan c e T I C : P 0107 2 6A . D 9 0 000 0 43 8 0 000 0 2 7 0 000 0 1 6 0 000 0 5 0 000 0 4 0 000 0 3 0 000 0 2 0 000 0 3 9 10 41 7 8 25 30 1 0 000 0 4 18 37 42 5 6 1112 1314151617 192021222324 26272829 31323334 3536 3839 40 0 5. 0 0 10 . 0 0 15 . 0 0 20 . 0 0 25 . 0 0 30 . 0 0 35 . 0 0 Ti m e - - > PM USA Presentation to LSRO 10/29-30/01 Pyrolysis Process
• Transformation of a compound into one or more other substances by heat in a low oxygen concentration environment – Decomposition into smaller fragments – Isomerization
PM USA Presentation to LSRO 10/29-30/01 Pyrosynthesis Process
• Formation of smoke components during the combustion, pyrolysis and distillation processes
PM USA Presentation to LSRO 10/29-30/01 Process of Smoke Formation Summary • Mainstream smoke is produced by a number of processes • Specific process which impacts an ingredient is dependent on the physical properties of the specific ingredient
PM USA Presentation to LSRO 10/29-30/01 Cigarette Construction
Tipping Paper Adhesive Seam Inner Adhesive Line
Plug Wrap
Perforated Zone (Ventilation)
Filter Plug
Tobacco Column
Cigarette Wrapper
PM USA Presentation to LSRO 10/29-30/01 Principal Cigarette Construction Parameters Controlling Smoke Yields
• Type of Tobacco • Tobacco Weight (Density) • Cigarette Paper • Filter Type – Efficiency (retention) • Filter Ventilation • Cigarette Geometry – Circumference –Length PM USA Presentation to LSRO 10/29-30/01 Processes Related to Cigarette Construction sidestream smoke
rod porosity filter ventilation cone Mainstream Smoke
diffusion filtration smoke generation
PM USA Presentation to LSRO 10/29-30/01 Principal Cigarette Construction Parameters Controlling Smoke Yields
• Type of Tobacco • Tobacco Weight (Density) • Cigarette Paper • Filter Type – Efficiency (retention) • Filter Ventilation • Cigarette Geometry – Circumference –Length PM USA Presentation to LSRO 10/29-30/01 Types of Tobacco
BURLEY BRIGHT ORIENTAL EXPANDED RECON STEMS
Air Cured Flue Cured Air Cured Bright Flue Cured Expanded Burley Type Stems Oriental Burley Type Flue Cured
High Filling Moderate Low Filling Excellent Mod. - High Power Filling Power Power Filling Power Filling Power (2X)
Excellent Variable Very Slow Fast Burn Fast Burn Burn Burn Burn
PM USA Presentation to LSRO 10/29-30/01 Tobacco Variability
• Natural product – Grown in many parts of the world • Crop year variation – Weather • Multiple crop years are used in US blended cigarettes
PM USA Presentation to LSRO 10/29-30/01 Typical US Blend
Components %
Burley 25 - 35 Bright 25 - 35 Oriental 3 - 5 Reconstituted 10 - 25 Stems 3 - 10 100
PM USA Presentation to LSRO 10/29-30/01 Tobacco Weight (Density) • US commercial brands have approximately 400 mg to 1 gram of tobacco • Reduced tobacco weight reduces machine smoked yield of smoke components, but also can reduce the physical stability of the cigarette – Compensate by using a higher filling power tobacco • Use expanded tobacco
PM USA Presentation to LSRO 10/29-30/01 Cigarette Paper
• Cigarette papers are constructed of: – Flax or wood fibers – Typically calcium carbonate as a color enhancing agent – Sodium and potassium citrate as burn rate modifiers • Resulting paper has a certain permeability – Measure of the volume of air that flows through a specified area of cigarette paper in a given unit of time--CORESTA units
PM USA Presentation to LSRO 10/29-30/01 Cigarette Paper Properties
• US commercial brands have paper permeability between 14 and 51 CORESTA units • Increased potassium and sodium citrate results in faster burning papers and reduces machine smoked tar yield per cigarette by reducing the number of puffs • Increased cigarette paper permeability decreases the amount of tobacco consumed during a puff and reduces machine smoked tar yield
PM USA Presentation to LSRO 10/29-30/01 Filter Types • Cellulose Acetate – Most common – Made of cellulose acetate •Paper – Offers higher smoke component removal efficiency, at the same pressure drop, but poor visual appearance – Made of pure cellulose • Combination carbon filter – A combination of a cellulose acetate or paper filter with carbon
PM USA Presentation to LSRO 10/29-30/01 CH OH H OH 2 O C C HH C O O H H OH C C H C C OH H H C O O C C H CH2OH H OH
ACETYLATION
CH H OAC 2OAC O C C H H C O O OAC H H C H C C OH H C H C O O C C H CH2OAC H OAC PM USA Presentation to LSRO 10/29-30/01 Single Component Filter
PM USA Presentation to LSRO 10/29-30/01
PM USA Presentation to LSRO 10/29-30/01 Cavity Filter (plug space plug)
PM USA Presentation to LSRO 10/29-30/01 Resistance to Draw (RTD) or Filter Pressure Drop
• The amount of suction that must be used to pull smoke through the filter • Measure of pressure required to force air through the filter at the rate of 17.5 mL/sec
PM USA Presentation to LSRO 10/29-30/01 Filter Efficiency (Retention)
• The percentage of the incoming smoke components that are removed by the filter • As the pressure drop increases for a given filter rod configuration, filtration efficiency increases due to a reduction in mainstream smoke velocity
PM USA Presentation to LSRO 10/29-30/01 Direct Interception
Fiber
Flow
PM USA Presentation to LSRO 10/29-30/01 Inertial Impaction
Flow direction
PM USA Presentation to LSRO 10/29-30/01 Diffusion
Fiber
Flow
PM USA Presentation to LSRO 10/29-30/01 Filter Efficiency (Retention)
• Particulate phase materials can be removed to some degree with a cellulose acetate or paper filter while gases (e.g., CO) are not removed • Use of a combination carbon filter can also reduce some gas phase materials but not CO
PM USA Presentation to LSRO 10/29-30/01 Filter Ventilation
• US commercial brands range from 0 to 81% ventilation • Increased ventilation causes: – Reduction in per-puff machine smoke concentration due to dilution with air from the atmosphere – Improved filtration efficiency of tobacco column and filter due to reduced aerosol velocity – Decreased tobacco burned during a smoking machine puff resulting in increased puff count – Increased diffusion of the gas phase out of the tobacco column
PM USA Presentation to LSRO 10/29-30/01 Cigarette Geometry
• Circumference – US commercial brands are 17 mm to 27 mm, most are 25 mm – Reduced circumference increases Resistance To Draw (RTD) • Length – US commercial brands are 70 to 120 mm, most are 85 or 100 mm – Longer length has the potential for more tobacco to be burned PM USA Presentation to LSRO 10/29-30/01 M a rl b o ro R a f f l e s b K i n g , H P 100, H P i EU U K tr GB S G B S B S m ok e C o ns t i t u e n t T a r , m g /c ig 1 3 1 2 N i c o t i n e , m g /c ig 0 . 9 1 .2 C O , m g /c ig 1 1 1 3 For m a l de hy de , ug/ c i g 3 8 4 1 A c e t a l de hy de , ug/ c i g 5 4 0 6 4 3 A c e t o n e , u g /c ig 2 8 7 3 3 5 A c r o le in . u g /c ig 5 1 6 0 P r opi ona l de hy de , ug/ c i g 5 0 5 6 C r ot ona l de hy de , ug/ c i g 2 0 2 8 M E K , ug/ c i g 6 6 7 8 B u t y la ld e h y d e , u g /c ig 3 4 4 8 H y dr oqui none , ug, c i g 5 4 7 5 R e s o r c in o l, u g /c ig 1 1 C a t e c hol , ug/ c i g 5 0 7 3 P h e nol , ug/ c i g 1 5 2 4 m + p - C a t e c h o l, u g /c ig 1 0 1 3 o- C a t e c h ol , ug/ c i g 3 6 B e nz o( a ) py r e ne , ng/ c i g 1 1 1 3 1 - A m i nona p ht ha l e ne , ng/ c i g 18 18 2 - A m i nona p ht ha l e ne , ng, c i g 11 10 3 - A m in o b ip h e n y l, n g /c ig 3 2 4 - A m in o b ip h e n y l, n g /c ig 2 2 N O , u g /c ig 1 5 6 1 1 8 HCN, u g / c i g 1 1 4 1 3 5 A mmo n i a , u g / c i g 1 8 1 2 1, 3- B u t a d i e n e , u g / c i g 46 54 Is o p r e n e , u g /c ig 3 8 5 4 6 6 A c r y lo n i t r ile , u g /c ig 1 1 1 1 B e n z en e, u g / c i g 4 4 4 4 T o lu e n e , u g /c ig 6 8 6 8 St y r e n e , u g /c ig 9 1 0 P y r i di ne , ug/ c i g 1 2 1 3 Q u in o l in e , u g /c ig 0 . 3 0 .6 NNN, n g / c i g 1 8 9 2 7 N A T , n g /c ig 1 6 0 4 3 NAB, n g / c i g 1 9 7 NNK, n g , c i g 1 0 4 3 4 pH 6 . 2 6 . 2 M e r c ur y , ng/ c i g 3 4 C a dm i u m , ng/ c i g 5 1 3 4 L e a d , n g /c ig 2 0 1 7 C h r o m i u m , n g /c ig B D L N Q Ni c k e l , n g / c i g B DL BDL Ar s e n i c , n g / c i g NQ NQ S e l e ni um , ng/ c i g B D L B D L G B S - G l oba l B e nc hm a r k i ng S t udy B B S - B r a z i l B e nc hm a r k i ng S t udy PM USA ABS - Au s t r a l i a n Co n s ti t u e n t S t u d y Presentation to LSRO 10/29-30/01 Cigarette Construction Summary
• Mainstream smoke concentration, including ingredient smoke concentration, is influenced by: – dilution air – filtration by tobacco – filtration by the filter or additive – outward diffusion
PM USA Presentation to LSRO 10/29-30/01 Overall Summary • A cigarette is surprisingly complex with many inter-related parts • Cigarettes are constructed with a natural, somewhat variable, biological matrix - tobacco • Mainstream smoke formation is dynamic • Mainstream smoke components, including ingredients, are impacted by a number of processes • Mainstream smoke components and ingredient concentrations are influenced by: – dilution air – filtration by tobacco – filtration by the filter or additive – outward diffusion • Approximately 4,000 constituents have been identified in smoke • Difficult to identify an ingredient added to tobacco due to the complex nature of smoke and low concentration of ingredients used
PM USA Presentation to LSRO 10/29-30/01