2. What tests can detect skin-sensitizing substances?

2.1 In vitro tests on living organisms

Three regulatory tests for cutaneous sensitization in animals and one in humans, based on T-cell mediation, have been validated.

Two tests are performed in albino guinea pigs according to the following scheme:

• sensitization induction ;

• latency/maturation time and cell proliferation (rest 15 days) ;

• triggering ;

• rating of cutaneous reactions erythema and oedema localized at the site of the triggering application.

For this last item, scoring is based on the following grid:

• 0 = no apparent change...