an approach to ingredient screening and toxicological risk assessment of flavours in e-liquids

Introduction:
This article outlines an approach to the screening and toxicological risk assessment of flavors in e-liquids. The authors propose a process for ingredient selection and review of existing toxicological evidence to ensure the safe use of flavors in e-cigarettes.

Key Points:

* The aerosolization process in e-cigarettes can introduce potential thermal breakdown and reaction products of compounds.
* The screening of in-going ingredients involves purity requirements, avoiding ingredients that are carcinogenic, mutagenic, or toxic to reproduction, and excluding respiratory sensitizers.
* a review of toxicological data on the ingredients should be conducted to identify any evidence of inhalation-specific issues that may make a compound unsuitable for use in an inhalation product.
* The use of toxicological thresholds of concern (TTCs) can be helpful when there is a lack of data on local and systemic toxicity.
* TTCs should be used to assess two classes of vaping aerosol compounds: ingredients where the supporting toxicological data is qualitative, and thermal degradation and reaction products of ingredients.
* The TTCs derived from inhalation data on consumer aerosol ingredients are proposed as appropriate for risk assessment of flavoring ingredients for e-cigarettes.
* a TTC of 1800 lg/day is proposed for Cramer class 1 compounds, and a TTC of 90 lg/day for Cramer class 2 and 3 compounds.

Main Message:
The article highlights the importance of a comprehensive approach to ingredient screening and toxicological risk assessment for flavors in e-liquids. The proposed process includes purity requirements, toxicological data review, and the use of TTCs to ensure the safe use of flavors in e-cigarettes. The authors suggest that the TTCs derived from inhalation data on consumer aerosol ingredients are appropriate for risk assessment of flavoring ingredients for e-cigarettes. Overall, the article emphasizes the need for rigorous safety assessments to protect consumers and ensure the safe use of e-cigarettes.

Costigan, S., and C. Meredith. “an approach to Ingredient Screening and Toxicological Risk assessment of Flavours in E-Liquids.” Regulatory Toxicology and Pharmacology 72, no. 2 (July 2015): 361–69. https://doi.org/10.1016/j.yrtph.2015.05.018.