Sensitization and testing of guinea pigs with cobalt chloride

Abstract

The guinea pig maximization, test was used to study the sensitizing potential of cobalt chloride; 1 % CoCl₂, was used for injection and 5 % for topical application. The animals were challenged twice; in series I epicutaneous testing was performed 3 weeks after sensitization and intradermal testing after yet another week. In series II the reverse schedule was used, i, e. intradermal testing after 3 weeks and epicutaneous after 4 weeks. CoCl₂ was found to be a grade V allergen. The differences between cobalt-exposed and control animals (which had been treated with Freund's adjuvant, petrolatum, occlusion, etc.) were statistically significant (P < 0.001), However, the administration of cobalt at the first challenge testing caused this difference to diminish.