Nickel release from metallic earrings: a surveyof the Danish market and validation of the nickel spot test.

Abstract

BACKGROUND\nExposure to nickel releasing earpiercing jewelrymay explainthepersistently highprevalence of nickel allergy in Europe.While nickel release from earrings is regulated,fieldstudies show that the regulation is not always respected.Moreknowledge is neededregarding the risk of piercing exposure including suitable screening methods.\n\n\nOBJECTIVE\nTo examine the proportion of earringson the Danish market that release more nickel than allowed, and to validate the use of the dimethylglyoxime(DMG) testas a screening tool.\n\n\nMETHODS\n304 earrings were purchased and tested with the DMG test and X-ray fluorescent (XRF) spectrometry.The level of nickel release was quantified in a selected subsample of 100 earrings by the European reference test EN 1811.The DMG spot test was validated against EN1811 at different thresholds.\n\n\nRESULTS\nExcessive nickel release according to the European regulation was found in45(14.8%) of tested earrings. The sensitivity of the DMG test decreased with reduced levels of nickel release (sensitivity of 45.2% at ≥0.2\u2009μg/cm2 /week vs. 61.1%at >0.5\u2009μg/cm2 /week).\n\n\nCONCLUSION\nExcessive nickel release is commonin earrings on the Danish market. Due to low sensitivity, the DMG test has limited use in screening ofearrings for research butmay be still beusedclinically. This article is protected by copyright. All rights reserved.