Hen's egg test on chorioallantoic membrane

The Hen's egg test on chorioallantoic membrane (HET-CAM), or hen's egg test is a test that can be used to test the toxicity or irritancy of substances. It is also often used to test vaccines. The highly vascularized chorioallantoic membrane (CAM) of a fertilized chicken egg as a biological model for mucous membranes. The CAM, which contains arteries, veins, and capillaries, is particularly sensitive to chemical irritants, making it a useful model for assessing irritation potential—especially for ocular irritancy. Due to its extensive vascularization, the CAM exhibits inflammatory responses similar to those observed in the conjunctival tissue of the eye. HET-CAM is considered an alternative to the Draize Eye Test and supports the principles of the 3Rs (Replacement, Reduction, and Refinement of animal use) in scientific research.

It is a CAM Assay. The product to be tested is applied to a special membrane. Such tests were first used because chicken eggs were easily available. As the respective membrane does not contain any nerve cells, it is likely that the developing bird embryo does not feel pain during the test. These tests are not considered to be animal testing.

This test can be used as a replacement for the Draize test, as it similarly detects irritation response in cosmetics. 

Test protocols can be found here  and here 

References

Category:Animal rights
Category:Toxicology