Determination of eugenol, anethole, and coumarin in the mainstream cigarette smoke of Indonesian clove cigarettes

Indonesian clove cigarettes (kreteks), typically have the appearance of a conventional domestic cigarette. The unique aspects of kreteks are that in addition to tobacco they contain dried clove buds (15–40%, by wt.), and are flavored with a proprietary “sauce”. Whereas the clove buds contribute to generating high levels of eugenol in the smoke, the “sauce” may also contribute other potentially harmful constituents in addition to those associated with tobacco use. We measured levels of eugenol, trans-anethole (anethole), and coumarin in smoke from 33 brands of clove-flavored cigarettes (filtered and unfiltered) from five kretek manufacturers. In order to provide information for evaluating the delivery of these compounds under standard smoking conditions, a quantification method was developed for their measurement in mainstream cigarette smoke. The method allowed collection of mainstream cigarette smoke particulate matter on a Cambridge filter pad, extraction with methanol, sampling by automated headspace solid-phase microextraction, and subsequent analysis using gas chromatography/mass spectrometry. The presence of these compounds was confirmed in the smoke of kreteks using mass spectral library matching, high-resolution mass spectrometry (±0.0002 amu), and agreement with a relative retention time index, and native standards. We found that when kreteks were smoked according to standardized machine smoke parameters as specified by the International Standards Organization, all 33 clove brands contained levels of eugenol ranging from 2490 to 37,900 μg/cigarette (μg/cig). Anethole was detected in smoke from 13 brands at levels of 22.8–1030 μg/cig, and coumarin was detected in 19 brands at levels ranging from 9.2 to 215 μg/cig. These detected levels are significantly higher than the levels found in commercial cigarette brands available in the United States.