Overview
ISO 10362-2:2013 specifies the Karl Fischer method for the determination of water in cigarette smoke condensates. It covers sample preparation (usually following ISO 4387 mainstream smoke collection or adapted non‑standard smoking), dissolution of condensate in solvent, and direct titration of an aliquot with Karl Fischer reagent. The standard defines reagents, apparatus, standardization and titration procedures, result expression and reporting requirements for laboratory and regulatory use.
Key topics and technical requirements
- Principle: dissolve smoke condensate in anhydrous solvent (propan-2-ol) and determine water content by Karl Fischer titration.
- Scope: applies to smoke condensates from ISO 4387 machine smoking and to condensates from non‑standard smoking with appropriate notes in reports.
- Reagents:
- Propan-2-ol (extraction solvent) - account for its blank water content.
- Karl Fischer reagent (single or two-part formulations); pyridine‑free reagents preferred.
- Methanol (analytical grade) and freshly activated silica gel.
- Apparatus:
- Automatic or semi‑automatic Karl Fischer titrator.
- Solvent dispenser with silica gel moisture trap and continuous stirring.
- Syringes (20 µl and 10 ml), hot‑air oven, horizontal flask shaker.
- Procedure highlights:
- Glassware dried at (105 ± 5) °C and handled to avoid atmospheric moisture contamination.
- Extract filter disc(s) in propan-2-ol (typically 25 ml for 44 mm traps, 50 ml for 92 mm traps) and shake to produce condensate solution.
- Standardize Karl Fischer reagent daily using a 20 µl water injection to determine reagent water equivalent.
- Titrate 10 ml aliquots of blank and sample extracts; calculate water content per cigarette using the measured reagent equivalent and volumes.
- Quality and safety:
- Perform blanks (at least 2 per 100 cigarettes) and report atmospheric/test conditions.
- Note caution on waste handling and pyridine‑containing reagents.
Applications and who uses it
- Laboratories in the tobacco industry for product characterization and quality control.
- Regulatory bodies and testing laboratories that monitor cigarette smoke constituents.
- Analytical chemists performing smoke condensate analysis when gas‑chromatographic methods (ISO 10362‑1) are impractical.
- Useful for comparative product testing, formulation control and method verification when Karl Fischer titration is the selected water‑determination technique.
Related standards
- ISO 10362-1 - Gas‑chromatographic method for water in smoke condensate.
- ISO 4387 - Mainstream smoke collection and determination of total particulate matter.
- ISO 3308 - Routine analytical cigarette‑smoking machine conditions.
- ISO 3696 - Water for analytical laboratory use.
Keywords: ISO 10362-2:2013, Karl Fischer method, water determination, cigarette smoke condensate, smoke condensate analysis, ISO standards, ISO 4387, tobacco laboratory testing.
