Harmful and Potentially Harmful Constituents in the Filler and Smoke of Tobacco-Containing Tobacco Products

Abstract

The U.S. Food and Drug Administration established a list of 93 harmful and potentially harmful constituents (HPHCs) in tobacco products. While HPHCs are required to be submitted for tobacco products, knowledge gaps exist regarding which tobacco-containing tobacco product (TCTP, i.e., tobacco products that contain tobacco(s) as a component) types (cigarettes, cigars, roll-your-own tobaccos [RYOs], pipe tobaccos [pipes], smokeless tobacco products [STPs], waterpipe tobaccos [waterpipes]) and matrices (filler, smoke) contain which HPHCs. This study identified and addressed such gaps by conducting literature searches and measuring the amount of HPHCs in TCTP types and matrices. First, literature searches, performed for cigarettes, RYOs, and STPs for publications up to 2014 and for cigars, pipes, and waterpipes for publications up to 2016, identified knowledge gaps for the 93 HPHCs (or 119 HPHCs if cresols [ o -, m -, p -cresol] are counted as 3 and chlorinated dioxins/furans as 25) across TCTP types and matrices. Then, three ISO 17025 accredited laboratories including two subcontracted laboratories performed the HPHC quantifications. Inclusion of the HPHCs, TCTP types, and matrices in the study scope was also determined by the availability of validated analytical methods in each laboratory. Eleven (9%) HPHCs are quantifiable in all brands for all TCTP types and matrices, 33 (28%) HPHCs are not quantifiable in any brands of any TCTP type and matrix, and 74 (63%) HPHCs are quantifiable only in some brands across TCTP types and matrices examined. Understanding the quantifiability of HPHCs in each TCTP type and matrix can inform the scientific basis for manufacturers regarding the regulatory requirements for reporting HPHCs. The quantity of HPHCs observed can also inform the evaluation of the public health impact of HPHCs and public communications regarding the health risks of tobacco products.

Harmful and Potentially Harmful Constituents in E-Liquids and Aerosols from Electronic Nicotine Delivery Systems (ENDS)

“…This study finds that ENDS e-liquids contain a relatively lower number of quantifiable HPHCs (39% with 3% remaining knowledge gaps; Table S2) compared to TCTP fillers (32–49% with 1–48% remaining knowledge gaps; Table S2). This difference may become larger when the remaining knowledge gaps are addressed.…”

Health Risks Associated with Tobacco Consumption in Humans: An Overview

“…Of these four, the IARC identifies NNN and NNK as the primary tobacco-related cancer-initiating chemicals. When secondary and tertiary amines combine with nitriles, they produce nitrosamines, of which over 70 have been scientifically proven to be carcinogenic 15 (Figure 2).…”

Biomarkers of Electronic Nicotine Delivery Systems (ENDS) use

“…In studies focusing on understanding the health effects of tobacco use, biomarkers can demonstrate internal exposure to toxic chemicals present and emitted from specific products [ 10 , 11 ]. For example, biomarkers of exposure are used to characterize tobacco users’ exposure to harmful and potentially harmful constituents (HPHC), including nicotine, TSNAs, PAHs, VOCs, and toxic metals [ 12 ]. Although clinical outcomes such as respiratory and cardiovascular diseases and cancer are definitive endpoints in assessing the potential health risks of novel tobacco products, they can take decades to develop and thus are not always practical to determine quickly.…”