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. Hence, an understanding of the validity and limitations of generated data is important for industry and regulators alike to avoid unjustified 'out-of-compliance' situations, and consequent competitive and reputational concerns for manufacturers. This paper reviews smoke constituent regulation and provides examples of technical challenges and good practice. It discusses approaches used to standardize measurements; the role of the International Organization for Standardization; factors influencing result variability and limitations and possible misinterpretations of generated data. If smoke constituents regulation is to be introduced, a standardized, science-based approach must be the pre-requisite for the generation and comparison of data. Potential analytical and technical issues must be resolved in discussion, both before and after the implementation of regulation, to the benefit of the public, regulators and manufacturers.