A review of current smoke constituent measurement activities and aspects of yield variability.

An increasing number of initiatives to regulate cigarette smoke constituents beyond 'tar', nicotine and carbon monoxide are being launched. The objective of existing and proposed regulation is presumably either to gain a better understanding of product performance, to be able to discriminate between products, or to impose limits for selected constituents. However, without standardized analytical methods and measurement tolerances a meaningful comparison of data or verification against regulated limits is challenging if not impossible.

Some consequences of using cigarette machine smoking regimes with different intensities on smoke yields and their variability.

When smoking cigarettes under an intense regime with a combination of 100% ventilation blocking and high flow rates, as currently mandated by Health Canada, significant increases in filter temperatures and disproportionately high levels of mainstream smoke water and moisture accumulating in the spent filter were found when compared to other smoking regimes, especially for highly filter ventilated cigarettes. These effects have been reported to decrease cigarette firmness during the course of smoking, to alter filtration properties and efficiencies and to confound the measurement of particulate matter. The high filter temperatures generated also lead to significant amounts of vapour phase compounds desorbing from carbon filters and an over-estimation of the yields of these components.

Limitations in the characterisation of cigarette products using different machine smoking regimes.

It is recognised that no single machine smoking regime can represent the different behaviours of individual human smokers. It has been argued that the current ISO standard regime provides machine yields that are somewhat low for certain cigarette designs compared to human intake. Various cigarette machine smoking regimes have been proposed as options for regulatory use to provide data that reflect "average" or "maximum" yields as related to human intake.

A review of the UK methodology used for monitoring cigarette smoke yields, aspects of analytical data variability and their impact on current and future regulatory compliance.

The European Union (EU) requires that tobacco products are regulated by Directive 2001/37/EC through testing and verification of results on the basis of standards developed by the International Organization for Standardization (ISO). In 2007, the European Commission provided guidance to EU Member States by issuing criteria for competent laboratories which includes accreditation to ISO 17025:2005. Another criterion requires regular laboratory participation in collaborative studies that predict the measurement tolerance that must be observed to conclude that test results on any particular product are different.