Predicting skin sensitizer potency based on in vitro data from KeratinoSens and kinetic peptide binding: global versus domain-based assessment.

Three in vitro methods for the prediction of the skin sensitization hazard have been validated. However, predicting sensitizer potency is a key requirement for risk assessment. Here, we report a database of 312 chemicals tested in the KeratinoSens™ assay and for kinetic peptide binding.

Predicting the bioconcentration of fragrance ingredients by rainbow trout using measured rates of in vitro intrinsic clearance.

Bioaccumulation in aquatic species is a critical end point in the regulatory assessment of chemicals. Few measured fish bioconcentration factors (BCFs) are available for fragrance ingredients. Thus, predictive models are often used to estimate their BCFs.

Chemical reactivity and skin sensitization potential for benzaldehydes: can Schiff base formation explain everything?

Skin sensitizers chemically modify skin proteins rendering them immunogenic. Sensitizing chemicals have been divided into applicability domains according to their suspected reaction mechanism. The widely accepted Schiff base applicability domain covers aldehydes and ketones, and detailed structure-activity-modeling for this chemical group was presented.

Chemical basis for the extreme skin sensitization potency of (E)-4-(ethoxymethylene)-2-phenyloxazol-5(4H)-one.

(E)-4-(ethoxymethylene)-2-phenyloxazol-5(4H)-one, commonly referred to as oxazolone, is the most potent skin sensitizer in published databases as determined with the murine local lymph node assay. It has been used very widely in immunological research to induce and elicit skin sensitization reactions in experimental animals. Nevertheless, no detailed study on the reactivity of oxazolone with proteins or peptides has been published, which would rationalize its unique sensitization potential from a chemical point of view.

Use of in vitro testing to identify an unexpected skin sensitizing impurity in a commercial product: a case study.

Due to regulatory constraints and ethical considerations, the quest for alternatives to animal testing has gained a new momentum. In general, animal welfare considerations and compliance with regulations are the key drivers for this research. Mechanistically based in vitro tests addressing specific toxicological questions can yield new information, for example on reactive components, and thus in certain cases the in vitro tests are not only second choice replacements of a 'gold standard' animal test but can also be used to develop safer products.