The epiCS (previously called EST-1000) Skin Corrosion Test (SCT) can be used to assess the potential of chemicals to cause skin corrosion.
The test involves the exposure of the epiCS model to test chemicals and subsequent determination of cytotoxicity via the MTT assay. The epiCS model is a reconstructed epidermis consisting of proliferating and differentiating keratinocytes.
The model underwent external validation and the EURL ECVAM Scientific Advisory Committee (ESAC) subsequently peer reviewed the data. A recommendation followed that the method can reliably predict the corrosive potential of chemicals.
The results of the validation study, the ESAC statement and our recommendation will be soon available on TSAR, the Tracking System for Alternative methods towards Regulatory acceptance.
[collapsed]Skin corrosion usually refers to chemically induced full thickness destruction of skin tissue. It can also refer to any irreversible alterations in skin tissue that are the result of exposure to a chemical.
The potential of a chemical to cause skin corrosion is considered important for establishing protocols relating to safe handling, packaging and transportation of chemicals.[/collapse]
epiCS Skin Corrosion Test (SCT)
[collapsed]The test is based on the notion that skin corrosion is in part due to cytotoxic effects of chemicals. As such, the method involves the determination of cytotoxicity following exposure of the epiCS model to a test chemical.
The MTT assay is used to determine cytotoxicity, which is then expressed as a % of the negative control. A positive control is also included in the assay. The test is available as a commercial kit.[/collapse]
Animal testing replacement
[collapsed]The method is considered to have met the performance standards set out in OECD test guideline No 431 and as such can be used for regulatory purposes for determining the potential of chemicals to act as corrosives (or not).
Along with a number of other in vitro skin corrosion tests, the epiCS method is considered a replacement for the Draize rabbit skin corrosion test.[/collapse]
[collapsed]The epiCS Skin Corrosion Test (SCT) has been validated in a study involving four laboratories using a standardised set of 12 reference chemicals. Full details of the study are available in Hoffmann et al., 2005.
The study was not carried out by EURL ECVAM but the resulting data was subjected to peer review by ESAC.[/collapse]
Validation study outcomes
[collapsed]According to Hoffmann et al., 2005 the epiCS/EST-1000 method showed a very high predictive potential.
Data reported in the ESAC statement relating to this method indicates a specificity of 84.7%, a sensitivity of 100% and an overall accuracy of 92.4%.
For certain chemical classes there was a higher level of variability in predictive capacity, which was dealt with in subsequent ESAC statements.[/collapse]
EURL ECVAM recommendations
[collapsed]As a result of the review of data performed by ESAC, the epiCS method was recommended as being reliable for predicting the corrosive potential of chemicals and that the method meets the performance standards set out in OECD test guideline No 431.[/collapse]