POLYCYCLIC AROMATIC HYDROCARBONS IN THE MAINSTREAM SMOKE OF POPULAR U.S. CIGARETTESBY AN T. VU, KENNETH M. TAYLOR, MATTHEW R. HOLMAN, YAN S. DING, BRYAN HEARN, CLIFFORD WATSON

ACS JOURNAL OF CHEMICAL RESEARCH IN TOXICOLOGYJULY 30, 2015

PRESENTED BY: ROWENA FERRER

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TOBACCO SMOKE Leading cause of PREVENTABLE death Six million annual mortalities One half trillion dollars of economic damage worldwide each

year Complex composition of cigarette smoke includes many toxic substances

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OUTLINE What are Polycyclic Aromatic

Hydrocarbons? Sample Preparation Smoke Collection Solid Phase Extraction Gas Chromatography/Mass Spectrometry Results Conclusion

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POLYCYCLIC AROMATIC HYDROCARBONS

Benzo[a]pyrene (BaP)

IARC

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POLYCYCLIC AROMATIC HYDROCARBONS5

Environmental pollutants Found in tar, crude oil

PAHs do not naturally occur in tobacco plant

Complete Combustion: Hydrocarbon + O2 CO2 +

H2O Incomplete Combustion:

Hydrocarbon + O2 CO + C + H2O

POLYCYCLIC AROMATIC HYDROCARBONS

Also, found in some unburned tobacco products Pipe tobacco Chewing tobacco Snuff

fire cured tobacco varieties: slow oxidation to reduce chlorophyll content for flavor

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OVERVIEW7

ISO CI

PUFF INTERVAL 60 s 30 sPUFF DURATION 2 s 2sVOLUME 35 mL 55 mLVENTILATION UNBLOCKED BLOCKED

FDA requires HPHC tobacco testing and reporting1. Levels of 14 PAHs in the smoke of 50

commercial U.S. cigarette products using GCMS International Organization of Standardization (ISO) Canadian Intense (CI)

2. Potential correlations between BaP and other individual PAHs

MATERIALS 35/50 cigarettes used, make up 54%

of the total U.S. cigarette market share based on sales volume

The 50 cigarettes consisted of 23 brands with various sub-brands, lengths, sizes, and package types

Regular, menthol, or Turkish flavored All contained a cellulose acetate filter 3R4F Reference cigarettes from

University of Kentucky

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METHODS Calibration Curve

Varying amounts of standard stock solution containing all 14 PAHs was prepared in methanol

25 μL of 13C PAH internal standard solution

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3R4F REFERENCE CIGARETTE

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Research standard designed to represent tobacco composition of US consumer tobacco products

Do not include any additional flavorings

Smoked as QC samples during each smoking run

SAMPLE PREPARATION11

Cigarettes smoked to 23 mm to butt length in ASM500 16-port smoking machine

ISO CI

Each CFP was placed in 10 mL of methanol in 13 mL vial and then decanted.

Zymark LV Evaporator to reduce volume to 2 mL.

Any remaining particulate matter was removed with 0.45 μL nylon syringe filter.

3.5 mL HPLC grade water

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SOLID PHASE EXTRACTION

GILSON 215 SPE

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SELECTED ION MONITORING GC/MS

The cyclohexane extracts were evaporated to approximately 0.5 mL, and a 1 μL aliquot was used for GC/MS analysis

AGILENT 6890/5973

QUADRUPOLE MASS ANALYZER

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SELECTED ION

MONITORING

Current

ADVANTAGES & DISADVANTAGES OF GC/MS

Advantage Good at separating

complex mixtures into components

Disadvantage Possibility of co-

elution

Advantage Most powerful

detector for chromatography

Disadvantage Possibility of similar

patterns of ionized fragments

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GAS CHROMATOGRAPHY MASS SPECTROMETRY

PAH LEVELS IN 3R4F AND 2R4F REFERENCE CIGARETTES

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*Y axis depicts PAH yield on a log-2 scale Determination of 14 PAHs in Mainstream Smoke from Domestic

Cigarettes, Yan Ding

Coefficients of Variance17

TOTAL PAH YIELDS18

Abbreviated: American Spirit Blue

AMERICAN SPIRIT BLUE19

Tobacco Mass 881 mg/cig 216 mg more than average

tobacco mass of other 49 cig (665 mg/cig)

Flue Cured Tobacco Produces higher molecular

weight PAHs

AVERAGE YIELDS OF INDIVIDUAL PAHs FOR ALL 50 COMMERICAL CIGARETTES

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log

2 sc

ale

SPIDER CHART SHOWING BaP COORELATION WITH INDIVIDUAL AND

TOTAL PAHs21

LINEAR RELATIONSHIPS BETWEEN BaP YIELDS WITH OTHER PAHs IN ISO

REGIMEN22

LINEAR RELATIONSHIPS BETWEEN BaP YIELDS & OTHER HIGH MOLECULAR WT.

PAHs USING CI REGIMEN23

TO CONCLUDE…24

Survey of PAH mainstream smoke yields for popular U.S. cigarettes having a wide range of smoke deliveries

All 14 PAHs found in all 50 test cigarettes American Spirit Blue, Winston Red, Winston Red

100s Carlton White 100s & Marlboro Silver PAH yield vs molecular weight Very strong correlations between BaP and those with

similar molecular weight and chemical structures Sample preservation?

QUESTIONS…25

Cigarette Model26

STATISTICS P-Value: measure of statistical

significance of correlation (>0.5) Coefficients of determination (r2):

measure of the goodness of fit Between smoke deliveries of BaP and and

other PAHs on on the regression lines

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PEARSON CORRELATION COEFFICIANT (r)28

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