The Nickel Spot Test consists of an ammoniacal solution of Dimethylglyoxime (DMG) for the detection of nickel in various metallic objects. DMG produces a bright, reddish-pink insoluble salt with nickel. The Spot test detects free nickel down to a limit of 10 ppm (parts/million)1. The sensitivity threshold of most nickel allergic patients is above 11 ppm. Some strongly allergic patients will however still react to objects releasing amounts below the threshold of the test.

1. Put a few drops of the reagent solution onto the cotton tip to moisten it.
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2. Rub the metal surface of the suspected object intensively for up to 1 minute with the cotton tip.
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3. Observe the cotton tip for a change in color to reddish-pink.
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4. A color change of this nature indicates the presence of free nickel.

We hope that the Nickel Spot Test will be of benefit to you in order to avoid exposure to nickel thereby minimizing contact dermatitis caused by nickel releasing objects.

R.J.G. Rycroft, T. Menne, P.J. Frosch
Textbook of Contact Dermatitis, 2nd edition, (1995) ISBN 3-540- 57943-5 Springer-Verlag Berlin, Heidelberg, New York.