Evaluation of the safety of two complex cosmetics ingredients
Client
A chemicals manufacturer.
Background
The client was interested in extending the conditions of use of two of its manufactured surfactants to cosmetics and requested a risk assessment in order to evaluate their safety in a range of rinse-off and leave-on products. The two surfactants are each a mixture of several different structurally-related chemicals.
Project goals
To conduct a thorough review of the available relevant toxicological data, and to establish the safety of proposed levels of use in a range of different cosmetic products.
Approach and outcome
Exposure regimens for cosmetics were established based on the latest Notes of Guidance (NoG) from the European Commission’s Scientific Committee on Consumer Safety (SCCS). Retention factors (the amount of product available for uptake; particularly important for rinse-off products which may only be in brief contact with the skin or hair) were also considered. Bibra calculated exposures to the surfactants from the proposed levels of use and converted these to Systemic Exposure Doses (SEDs) using SCCS defaults.
Toxicity data on the various constituents of the two surfactants, and on structurally similar read-across compounds, were identified through literature searches using the bibra in-house TRACE database and external data sources. All relevant endpoints and routes of exposure were considered, and key studies were summarised.
A human health risk assessment of possible local and systemic exposures from the two surfactant mixtures was conducted in line with the SCCS NoG, assuming additive toxicity for the structurally-related constituents. Health-precautionary points of departure were identified and converted to systemic doses (PoDsys). These were compared with the SEDs for consumers to come up with Margin of Safety (MoS) values. The MoS figures were considered in the context of sources of uncertainty to allow conclusions on health risks. In cases where the MoS values were not sufficient to rule out health risks, bibra proposed concentrations of surfactant that could be considered tolerable, giving an acceptable MoS.
