Skin Irritation (OECD TG 439)

Use EpiDerm to determine the skin irritation potential of chemicals or formulations including liquids, solids, gels, lotions, ointments or creams. Skin irritation results are acquired within 3 days.


EpiDerm tissues are equilibrated overnight under standard culture conditions (37 C, 5% CO2, 95% RH) with EpiDerm Assay Media (EPI-100-NMM). 18-24 hours later tissue culture supernatants are aspirated and replaced with fresh, pre-warmed media. Tissues are exposed to test material and controls for 60 minutes. Following exposure, tissues are thoroughly rinsed and transferred to fresh culture medium. After a 24 hour post exposure incubation period, culture medium is collected for the optional analysis of cytokines and replaced with fresh medium for an additional 18 hours. Tissue viability is then determined by the MTT Assay.


The determination of skin irritation potential of test materials is based on tissue viability.  According to the EU and GHS classification (R38 / Category 2 or no label), an irritant is predicted if the mean relative tissue viability of triplicate tissues exposed to a test material is reduced below 50% of the mean viability of the negative controls.


SIT Graph

The EpiDerm Skin Irritation Test (SIT) is a formally validated in vitro method for the accurate and reliable prediction of skin irritating and non-irritating test materials.  This test method is a stand-alone in vitro alternative to animal skin irritation testing.


Download the EpiDerm Skin Irritation Test Protocol

Watch the EpiDerm Skin Irritation Test Training Video

For more information, view Technical References.

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