Prevalence of delayed hypersensitivity to the European standard series in a self-selected population.

There are limited reports of the prevalence of positive reactions in healthy adults to patch tests with standard allergens; there are no recent comprehensive studies from Australia. Healthy adult volunteers (n = 219) from the Western Australian community were patch tested using the European standard series of allergens. Seventy-seven (35%) reacted to at least one allergen, positive patch tests being most prevalent to nickel sulfate (20%), potassium dichromate (9%), cobalt chloride (6%) and fragrance mix (4%). Prevalence of positive patch tests to nickel and chromate was higher than that reported for another healthy population, which may stem from self-selection of volunteers or geographical differences, including extent of exposure to allergens.