Experiences with Freund's complete adjuvant test (FCAT) when screening for contact allergens in colophony.

A procedure, using Freund's complete adjuvant test (FCAT), for the determination of the allergenic potential of fractions and components in colophony of the gum rosin type is described and discussed. Gum rosin was shown to be a potent sensitizer in 11 test series (153 animals). FCAT is compared with the guinea pig maximization test (GPMT). Gum rosin was a potent sensitizer according to this method as well. The FCAT method was found to be advantageous over the GPMT method in that it is technically simpler to use and a smaller amount of test substance is needed. However, closed challenge was preferred to the prescribed open challenge. The importance of statistical evaluation of the results obtained in predictive testing is stressed.