Contact sensitization of mice to nickel sulphate and potassium dichromate

The ability of nickel sulphate and potassium dichromate to induce contact sensitization in mice has been investigated. Topical exposure of mice to 0.5% potassium dichromate in dimethylsulphoxide (DMSO) under occlusion resulted in specific contact sensitization in each of 7 experiments. Although sensitization to nickel sulphate under the same conditions was weak and somewhat variable, evidence for significant levels of contact allergy was obtained in 4 of 7 experiments. In addition, repeated topical application of both nickel sulphate and potassium dichromate in DMSO was found to result in the induction of lymphocyte proliferative responses in lymph nodes draining the site of exposure. These data indicate that epicutaneous exposure to both metal salts may cause specific contact sensitization in mice.