Gold and Nickel Release From Jeweller-Purchased 10K and 14K Gold Earrings in Cysteine-Modified Artificial Sweat.

BACKGROUNDGold contact allergy is common, but its clinical relevance is often uncertain. A previous study of low-cost gold-plated earrings found frequent nickel release and detectable gold release under cysteine-modified artificial sweat.

OBJECTIVESTo assess surface composition and release of gold, nickel and copper from jeweller-purchased earrings marketed as 10K or 14K gold.

METHODSFive pairs of earrings were examined by scanning electron microscopy (SEM) with energy-dispersive spectroscopy (EDS). Release testing used cysteine-modified artificial sweat at pH 8.0 ± 0.2 and 30°C for 168 h. Metals were quantified by inductively coupled plasma mass spectrometry (ICP-MS).

RESULTSSurfaces consisted mainly of gold, copper, silver and zinc. EDS-detected gold ranged from 40 to 63 wt%, and nickel from 0.085 to 0.20 wt%. Nickel release was < LOD in all pairs. Gold release was detected from all pairs (median 0.057 μg/cm2/week, range: 0.016-0.15). Copper release exceeded gold release in all samples (median: 0.53 μg/cm2/week, range: 0.36-2.2).

CONCLUSIONJeweller-purchased 10K/14K gold earrings released measurable gold but not detectable nickel under cysteine-modified artificial sweat conditions. Gold release provides a plausible exposure pathway but does not establish sensitization or elicitation risk.

Abstract from PubMed