Exposure based waiving: The application of the toxicological threshold of concern (TTC) to inhalation exposure for aerosol ingredients in consumer products

Thresholds of Toxicological Concern for cosmetics-related substances: New database, thresholds, and enrichment of chemical space

“…It has also been used as a first-level screening tool to prioritize for review a large number of substances identified as needing an assessment under the Canadian Environmental Protection Act (Health Canada, 2016). Consideration has also been given to whether the TTC approach could be applied to human biomonitoring data (Becker et al, 2012) and to human exposures by non-oral routes (Carthew et al, 2009;Escher et al, 2010;Hennes, 2012;Kroes et al, 2007;Partosch et al, 2015).…”

Criteria for the Research Institute for Fragrance Materials, Inc. (RIFM) safety evaluation process for fragrance ingredients

“…The dermal sensitization threshold (DST) establishes a level below which there is no appreciable risk for the induction of sensitization, and is based on a probabilistic analysis of potency data for a diverse range of known chemical allergens (Safford, 2008, Safford et al, 2011. There has also been the suggestion that TTC can be applied to inhalation exposure and risk assessment (Kroes et al, 2007, Carthew et al, 2009, Escher et al, 2010, Drew and Frangos, 2007. With respect to inhalation exposure another important consideration is the potential for site of contact (local) effects in all parts of the respiratory tract.…”

“…The TTC principles, which were originally developed with a focus on systemic exposure following oral administration, have been extended to consider systemic exposure following topical application of cosmetic products (Blackburn et al, 2005, Kroes et al, 2007. More recently there have been analyses proposing that the TTC can be applied to inhalation exposure and risk assessment (Carthew et al, 2009, Escher et al, 2010, Drew and Frangos, 2007, Kroes et al, 2007. A key consideration with respect to inhalation is the development of separate Cramer Class TTC values for site of contact (local) effects.…”

Regulatory Aspects of Anticholinesterase Pesticides

“…The concept proposes that a low level of exposure with a negligible risk can be identified for many chemicals, including those of unknown toxicity, based on knowledge of their chemical structures (Kroes et al, 2005). The TTC concept has been widely discussed in the context of several applications such as the risk management of aerosol ingredients in consumer products (Carthew et al, 2009) and extracts used in cosmetics (Kroes et al, 2007;Re et al, 2009). The concepts have been utilized successfully in the risk management of flavoring agents (Kroes et al, 2005) and also in controlling concentrations of pesticides within the European Union (http://www.efsa.europa.eu).…”