Determination of Total Particulate Matter (TPM) and Tar in Cigarette Smoke – ISO 4387 / GB/T 19609 T

Determination of total particulate matter (TPM) and tar (nicotine-free dry particulate matter, NFDPM) in cigarette smoke is a core smoke-chemistry test used for regulatory reporting, product registration, labeling, and quality control throughout the tobacco industry. Testing is performed on linear or rotary smoking machines under standardized puffing regimes in accordance with ISO 4387, ISO 10315, ISO 10362-1 and the equivalent GB/T 19609 series. Accredited third-party laboratories report TPM, water, nicotine and tar in mg per cigarette to support compliance with tar ceilings and international disclosure requirements.

Technical Overview

Total particulate matter (TPM) is the particle-phase fraction of mainstream cigarette smoke that is retained on a high-efficiency glass-fiber Cambridge filter pad when cigarettes are smoked on a routine analytical smoking machine under strictly controlled conditions. Tar, more precisely defined as nicotine-free dry particulate matter (NFDPM), is obtained by subtracting the water and nicotine contents from TPM. Because tar excludes water and nicotine, it is the internationally recognized metric for smoke condensate yield, regulatory reporting, and product-to-product comparison.

The determination is governed by ISO 4387 and the equivalent Chinese national standard GB/T 19609, supported by a family of companion methods: ISO 8243 (sampling), ISO 3402 (conditioning atmosphere), ISO 3308 (smoking machine definitions and standard conditions), ISO 10315 (nicotine by gas chromatography), ISO 10362-1 (water by gas chromatography), and ISO 8454 (carbon monoxide in the vapor phase). All results are expressed in milligrams per cigarette, usually reported to the nearest 0.1 mg.

Reliable tar data are essential for compliance with mandatory ceilings such as the EU Tobacco Products Directive limits of 10 mg tar, 1 mg nicotine and 10 mg carbon monoxide per cigarette, the tar-yield ceilings enforced by Chinese tobacco regulations, and the disclosure obligations arising from the WHO Framework Convention on Tobacco Control. The same data underpin daily manufacturing quality control, research and development of lower-yield designs, and market surveillance.

Testing Samples

Conventional Cigarettes

King-size and regular-format cigarettes of all blend styles (Virginia, burley, oriental or blended) constitute the principal sample type. A representative sample taken in accordance with ISO 8243 is required, typically 200 to 500 cigarettes (approximately one to two cartons) per lot, with an additional reserve for repeat determinations.

Slim, Super-Slim and Specialty Formats

Reduced-circumference and non-standard formats can be tested with the same core method, with adjustments to pad handling and cigarette positioning documented in the test report. These formats are increasingly common in low-tar product lines and require particular attention to butt-length marking and port sealing.

Cigarillos, Cigars and Other Combustible Products

Larger combustible tobacco products can be characterized using the same analytical principle with adapted published methods; the laboratory confirms the applicable puffing parameters, pad size and butt length prior to testing.

Sample Condition and Conditioning

Samples must arrive in intact original packaging and be conditioned for a minimum of 48 hours at 22 °C ± 2 °C and 60 % ± 5 % relative humidity (ISO 3402) before marking, selection and smoking. Cigarettes are screened for length and weight uniformity, and non-conforming units are rejected so that the smoked sample is representative of the lot.

Testing Items

The standard smoke-chemistry deliverables for a cigarette tar determination include:

• Total particulate matter (TPM), in mg per cigarette
• Water content of the particulate phase, in mg per cigarette
• Nicotine content of the particulate phase, in mg per cigarette
• Tar, i.e. nicotine-free dry particulate matter (NFDPM), in mg per cigarette
• Mean puff count per cigarette and, optionally, per-puff yields
• Carbon monoxide in the vapor phase, in mg per cigarette, completing the tar–nicotine–CO triad required by most regulatory schemes
• Extended smoke toxicant screening (carbonyls, phenols, hydrogen cyanide, aromatic amines, benzo[a]pyrene and other constituents) under intense puffing regimes, where required

Testing Methods

Sampling and Conditioning

Samples are drawn per ISO 8243 and equilibrated in the ISO 3402 atmosphere. After conditioning, each cigarette is marked at the target butt length, defined as the filter length plus overwrap plus 3 mm, or 23 mm, whichever is greater, and outliers in weight or length are excluded from the test population.

Machine Smoking under the ISO Regime

Cigarettes are smoked on a linear or rotary analytical smoking machine operating at the ISO standard conditions: puff volume 35.0 mL, puff duration 2.0 seconds, puff interval 60 seconds, bell-shaped flow profile, and no blocking of filter ventilation. The number of cigarettes is selected so that each pre-weighed 44 mm Cambridge filter pad collects between 5 mg and 100 mg of TPM; 20 cigarettes per determination is typical, with the count increased for very low-yield products. Where carbon monoxide is required, the vapor phase is collected in a gas bag for subsequent analysis.

Alternative Intense Puffing Regimes

For jurisdictions and research programs requiring more aggressive conditions, the Health Canada Intense protocol is applied: 55 mL puff volume, 2-second duration, 30-second interval, and 100 % blocking of ventilation holes. Intense-regime yields are systematically higher and must never be compared directly with ISO values.

Gravimetric Determination of TPM

Pads are equilibrated in the laboratory atmosphere before and after smoking and weighed on an analytical balance readable to 0.1 mg. TPM is the net mass gain of the pad, corrected for blank pads exposed on unlit ports, divided by the number of cigarettes smoked.

Determination of Nicotine and Water

The spent pad is extracted with isopropanol containing internal standards. Nicotine is quantified by gas chromatography with flame ionization detection (ISO 10315 and the corresponding GB/T method), and water by gas chromatography with thermal conductivity detection (ISO 10362-1); Karl Fischer titration (ISO 10362-2) is an accepted alternative for water. Calibrations, certified reference materials and control charts are maintained throughout the sequence.

Calculation and Reporting of Tar

Tar (NFDPM) is calculated as TPM minus water minus nicotine, expressed in mg per cigarette. The test report states the smoking regime, machine type, butt length, number of cigarettes, individual and mean values for TPM, water, nicotine and tar, together with any deviations. Repeatability is verified against the statistical limits published in ISO 4387.

Quality Assurance

Accredited third-party laboratories operating to ISO/IEC 17025 verify leak integrity, puff volume and puff profile before every run, monitor reference cigarettes as internal quality controls, and perform replicate determinations to confirm that precision criteria are met before results are released.

Applications

TPM and tar determination services are used across the product life cycle:

• Regulatory registration of new cigarette products and demonstration of compliance with statutory tar ceilings, including the EU limits of 10 mg tar per cigarette
• Periodic government reporting of tar, nicotine and carbon monoxide yields
• Manufacturing quality control, trend monitoring and batch release decisions
• Research and development of blends, papers, filters and ventilation designs targeting specific yield levels
• Competitive benchmarking and market surveillance of retail products
• Support for pack labeling and export certification in jurisdictions mandating yield disclosure
• Inputs for exposure estimation, toxicological assessment and scientific publications
• Conformity assessment and arbitration in trade disputes

FAQ

What is the difference between TPM and tar?

TPM is everything collected on the Cambridge filter pad, including water and nicotine. Tar (NFDPM) is TPM with the water and nicotine subtracted, representing the dry, nicotine-free particulate fraction of the smoke condensate.

Which standards govern the determination?

The core method is ISO 4387 or its Chinese equivalent GB/T 19609, supported by ISO 8243 for sampling, ISO 3402 for conditioning, ISO 3308 for machine conditions, ISO 10315 for nicotine, ISO 10362 for water and ISO 8454 for carbon monoxide.

How many cigarettes are needed for a test?

A representative submission of roughly 200 to 500 cigarettes is normally sufficient. Each analytical determination typically smokes 20 cigarettes, with the count increased for very low-tar products so that the pad collects at least 5 mg of TPM.

How are the results expressed?

TPM, water, nicotine and tar are reported in milligrams per cigarette, rounded to 0.1 mg, together with the puff count and the smoking regime used.

Why are Health Canada Intense results higher than ISO results?

The intense protocol uses a 55 mL puff every 30 seconds with all ventilation holes blocked, which draws substantially more smoke through the rod. The two regimes are deliberately different and results from them are not interchangeable.

Can this method be applied to heated tobacco or e-cigarettes?

Not directly. Aerosol-generating products require adapted pad arrangements, puffing parameters and aerosol capture appropriate to their operation, and the laboratory should be consulted to confirm the applicable approach before submission.

What is the typical turnaround time?

Following sample conditioning, routine TPM and tar determinations are generally completed within five to ten working days, with extended smoke-chemistry panels requiring additional time depending on the analyte list.