No abstract

The U.S. Food and Drug Administration (FDA) has regulatory authority over e-cigarettes, parts and components. Many e-cigarettes currently marketed are open systems. Closed systems may allow less manipulation and may influence the safety of these products. This study provides valuable information on ways that open system e-cigarettes are used and it can inform safety tests that can be conducted by the FDA to determine whether or not these products should remain on the market. Additionally, our definitions of unorthodox use can be incorporated into the Population Assessment of Tobacco on Health Study to better understand the prevalence of these behaviors.

Two common food preparation techniques, baking and fermentation, do not substantially affect the carbon or nitrogen isotopic signature of grain-based foods. Mass-balance equations can be used to accurately estimate the isotopic signature of multi-ingredient food items for which quantitative ingredient information is available.