RESUMEN
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.
Asunto(s)
Contaminación por Humo de Tabaco/análisis , Contaminantes Atmosféricos/análisis , Monitoreo del Ambiente/métodos , Regulación Gubernamental , Laboratorios , Reproducibilidad de los Resultados , Contaminación por Humo de Tabaco/legislación & jurisprudenciaRESUMEN
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. Less adsorption on or more desorption from carbon filters was found for compounds with the highest volatility. Therefore, yield data from the intense regime may not reflect the effectiveness of cigarette design features to reduce certain smoke components that occurs when products are smoked under conditions closer to those used by the majority of smokers in real world situations. In addition, a combination of these interacting factors may explain the worse level of between-laboratory reproducibility data for particulate matter measurement obtained during intense machine smoking. Among-laboratory data variability for vapour phase components, other than carbon monoxide, and for particulate phase components, other than nicotine, still needs to be evaluated in collaborative studies. Before proposing smoking regimes as tools to evaluate smoke emissions, it is essential to understand these various interacting factors and subsequent uncontrolled effects that such regimes can generate and the limitations of their use. These observations imply that higher tolerances may need to be set and taken into account when smoking under the intense regime before deciding that, for a given product, there are real differences between the yields determined in different laboratories.
Asunto(s)
Monóxido de Carbono/análisis , Nicotina/análisis , Humo/análisis , Fumar , Breas/análisis , Canadá , Monóxido de Carbono/química , Celulosa/análogos & derivados , Filtración , Humanos , Nicotina/química , Breas/química , Temperatura , Ventilación , AguaRESUMEN
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. Some public health representatives have proposed that the intense regime mandated for testing in Canada with 100% of the ventilation holes in the cigarette filter blocked, should be used for product characterisation and that it is not necessary that it should reflect general human smoking behaviour. We believe that this is a flawed approach because our studies and those of other workers demonstrate that the conditions generated in the cigarette when using this intense machine smoking regime are extreme in comparison to the conditions found for regimes based more realistically on human smoking. In this paper, we provide data to show that smokers modify their smoking intensity over the course of smoking in response to changes in draw resistance, smoke concentrations and smoke temperatures. We compare changes in and interactions between these parameters during puffing when smoking cigarettes of different designs. Cigarettes were smoked using various machine smoking regimes previously proposed for smoke testing as well as a regime based on human smoking data from an 'in-house' study. Puffing parameters were derived from this study to represent the 'average smoker' under laboratory conditions and equivalent to the 90th percentile when the studied smokers smoked under natural conditions. Biomarker data from human uptake studies have shown that ventilation is an effective cigarette design tool to reduce total smoke constituent uptake in humans so demonstrating that any blocking of filter ventilation is far from 100%. Likewise, this current work also shows how smokers modify their smoking behaviour in ways not well reflected by the 100% ventilation blocking regime. It seems logical that any machine smoking regime chosen for future product regulation should reflect these findings for it to have valid public health relevance. In addition, it seems misguided to discourage product design features, such as ventilation, which clearly can provide products with reduced human smoke exposure, just to maintain the dogma, counter to the scientific evidence, that there must be a regulatory regime with 100% ventilation blocking.
Asunto(s)
Nicotiana , Humo , Fumar , Biomarcadores , Filtración , Humanos , Nicotina , Material Particulado/análisis , Material Particulado/toxicidad , TemperaturaRESUMEN
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. However, differences will always occur when comparing overall data across products between different laboratories. A forum for technical discussion between laboratories testing products as they are manufactured and a Government appointed verification laboratory gives transparency, ensures consistency and reduces apparent compliance issues to the benefit of all parties. More than 30years ago, such a forum was set up in the UK that continued until 2007 and will be described in this document. Anticipating further testing requirements in future product regulation as proposed by the Framework Convention on Tobacco Control, cooperation between accredited laboratories, whether for testing or verification, should be established to share know-how, to ensure a standardised level of quality and to offer competent technical dialogue in the best interest of regulators and manufacturers alike.