Quantitative risk assessment of tobacco products: A potentially useful component of substantial equivalence evaluations

Abstract

Quantitative risk assessment (QRA), a scientific, evidence-based analytical process that combines chemical and biological data to quantify the probability and potential impact of some defined risk, is used by regulatory agencies for decision-making. Thus, in tobacco product regulation, specifically in substantial equivalence (SE) evaluations, QRA can provide a useful, practical, and efficient approach to address questions that might arise regarding human health risk and potential influence on public health. In SE reporting, when differences in product characteristics may necessitate the determination of whether a new product raises different questions of public health, the results from QRA are a valuable metric. An approach for QRA in this context is discussed, which is modeled after the methodology for assessment of constituent mixtures by the US Environmental Protection Agency for environmental Superfund site assessment. Given the intent in both cases is an assessment of the public health impact resulting from the totality of exposure to a mixture of constituents, the application is appropriate. Although some uncertainties in the information incorporated may exist, relying on the most appropriate of the available data increases the confidence and decreases the uncertainty in the risk characterization using this data-driven methodology.

Aerosol Gas-Phase Components from Cannabis E-Cigarettes and Dabbing: Mechanistic Insight and Quantitative Risk Analysis

“…Machine smoking attempts to imitate realistic use but is only an approximation. 52 In this study, a puff profile set by the Cooperation Center for Scientific Research Relative to Tobacco (CORESTA) for e-cigarettes was chosen given the functional similarity of these devices to e-cigarettes; however, puffing topography for CEVPs has not been studied, which represents another source of systematic error of unknown magnitude in the work herein. When calculating ELCR and HI, it is assumed that 100% of each component is absorbed and that the total risk is the sum of the risk from each individual component, which may over- or underestimate the total risk.…”

“…ELCR as defined in Marano et al 52 for each HPHC i for which an IUR value exists was calculated using eq 2, adapted from Marano et al: 52 where CY i is the yield for a given gaseous HPHC, CU is the consumption unit, CR is the consumption rate, ED is the exposure duration, EF is the exposure frequency, IR is the inhalation rate, and AT C is the averaging time for cancer effects. CU is a consumption method-dependent unit (vaping: CU = puffs, dabbing: CU = dabs, and smoking: CU = joints).…”

“…HQ, as previously defined, 52 for a given component i (HQ i ) for which an REL exists was calculated using eq 4, adapted from Marano et al: 52 where AT NC is the averaging time for noncancer effects, which averages component intake over the ED, for a value of 19723.5 days assuming an ED of 54 years. HI, as previously defined, is the sum of HQ for all components for which an REL exists:…”

“…51 Cancer risk may be approximated using the excess lifetime cancer risk (ELCR) and noncancer risks using the hazard index (HI). ELCR, the incremental probability of contracting cancer upon specified conditions of exposure to a carcinogen, 52 is derived from the inhalation unit risk (IUR), an estimate of the increased risk (i.e., above baseline) of developing cancer due to exposure to a 1 μg/m 3 concentration of a given chemical. 53 The reference exposure level (REL) is an estimate of an air concentration that is not likely to create an appreciable risk in humans after continuous inhalation and is calculated in reference to a given symptom that occurs after chronic exposure.…”

“…ELCR and HQ values for individual chemicals are summed to yield total ELCR (ELCR T ) and HI, respectively, which may be used to guide policy decisions regarding environmental cleanup projects and consumer products. 52…”