AISI 316L Stainless-Steel Ear Piercing Post Assembly Does Not Cause Dermatitis in Nickel-Sensitive Subjects

Twenty-three female and 2 male subjects, documented to be sensitive to nickel by history and diagnostic patch testing, were pierced with American Iron Steel Institute (AISI) 316L stainless-steel ear piercing post assemblies (The Ear Piercing Manufacturers of Europe, UK), AISI 316L having a specification that includes a nickel content of between 10 and 14%. After piercing, the subjects were examined on days 7, 14, 30 and 42. Seven of the ear piercing post assemblies collected at random from the subjects at the end of the study and 10 unused post assemblies selected at random were analysed for nickel content and release. None of the nickel-sensitive patients showed signs of nickel dermatitis during the study. The nickel content of the ear piercing post assemblies collected from patients was reported as being between 11.5 and 12.9%, and the calculated rate of nickel release was below the detection limit of the method, thus recorded at <0.05 µg/cm2/week. By comparison, the nickel content of the unused post assemblies was reported to be between 9.93 and 10.5%, and the calculated rate of nickel release was between 0.11 and 0.21 (mean: 0.15) µg/cm2/week. These results suggest that the AISI 316L stainless-steel ear piercing post assemblies do not elicit adverse reactions to nickel in previously sensitized subjects.