A. Ponka et A. Ekman, Insensitivity of the routine dimethylglyoxime test for detecting release of nickel from earrings, SCI TOTAL E, 224(1-3), 1998, pp. 161-165
The Helsinki City Centre of the Environment tested two methods, dimethylgly
oxime (DMG) and atomic absorption spectrometry (AAS), for detecting nickel
release in piercing earrings. The DMG screening test was performed in two s
lightly different ways, with and without ethanol and heat prehandling. All
30 pairs of earrings tested, totalling 66 objects, were negative. However,
according to our AAS test, 25 of the 66 objects (38%) released greater than
or equal to 0.05% of nickel, the mean amount being 2.1% and the maximum 12
%. When measured by AAS after artificial sweat treatment, 11 objects releas
ed more than 0.5 mu g/cm(2) per week of nickel, the mean amount being 3.4 m
u g/cm(2) and the range < 0.1-84 mu g/cm(2). After this sweat treatment, ni
ne of the objects (14%) were positive in DMG tests. These findings indicate
that the DMG test is unreliable for detecting nickel release from jewelry.
Quality control of consumer items should be performed by laboratories that
have quantitative analysis methods for such investigations. (C) 1998 Elsev
ier Science B.V. All rights reserved.