Population biomarker estimates and tobacco exposure: Comment on the article by Roethig et al.

We read with great concern the recently published article by Roethig et al. (2009) on population estimates for biomarkers of exposure to cigarette smoke in adult U.S. cigarette smokers published in the October issue of Nicotine and Tobacco Research. The title and conclusions of this work—namely that they provide population-based estimates of biomarkers of exposure in tobacco smokers—are patently misleading, given a number of significant design flaws as summarized below: Regardless, given the serious design flaws of this study, all readers of Nicotine and Tobacco Research should be strongly advised that the “population” estimates provided therein should not be used to estimate “baseline” biomarker levels in U.S. smokers for any exposure reductions in future generations of smokers.