Ear piercing--a cause of nickel allergy in schoolgirls?

960 schoolgirls of ages 8, 11 and 15 years were investigated regarding the frequency of ear piercing and the prevalence of nickel and cobalt allergy. 72% had had their ears pierced. The prevalence of nickel allergy in the whole material was 9%, among girls with pierced ears 13% and among those without pierced ears 1%. The results show that the prevalence of nickel allergy is just as high among schoolgirls as among adult women. There is a clear relationship between ear piercing and induction of nickel allergy. Prophylactic measures to reduce the prevalence of nickel allergy should be directed against this risk factor.