How nickel release is tested (and the spot test kits)

Two different questions

“Does this item contain nickel?” and “does this item release nickel onto skin?” are not the same question, and the tests for them are not interchangeable. This page covers how release is measured in the EU framework, what the home dimethylglyoxime (DMG) spot test can and cannot tell you, and where the US stands. We work from documents and have not tested any jewelry or kits ourselves, and we do not name or recommend any kit.

For the allergy itself, DermNet (retrieved 2026-11-14) says nickel allergy is diagnosed by clinical history and patch tests, and that it is essential for affected people to avoid skin contact with nickel-containing metals. Our guide to nickel allergy and jewelry covers the background.

How the EU frames release

The EU rule is written as a release rate, not a percentage of metal. In the consolidated text of the REACH Regulation (Regulation (EC) No 1907/2006, version of 1 January 2021, retrieved 2026-11-14 through the EU Publications Office), the nickel restriction covers three points we could read:

• Post assemblies inserted into pierced ears and other pierced parts of the body, unless the rate of nickel release is less than 0.2 micrograms per square centimetre per week. The text calls this a migration limit.
• Parts of articles coming into direct and prolonged contact with the skin, where the release rate is greater than 0.5 micrograms per square centimetre per week.
• Articles with a non-nickel coating, unless the coating is enough to keep release from the parts in direct and prolonged contact with the skin from exceeding 0.5 micrograms per square centimetre per week for at least two years of normal use.

The passage we retrieved gives these limits but not the full list of which articles fall under them. A 1996 review abstract (PMID 9007370, Contact Dermatitis), written as the Nickel Directive was coming into force, names earrings, watchstraps and zippers as examples of products in direct and prolonged skin contact. It also describes the then-directive as setting a concentration cap of 0.05% for post assemblies, a figure we did not find in the consolidated text excerpt, so treat it as historical context. Our guide to the EU nickel directive and jewelry covers the rule in more depth.

The coating point matters for plated pieces. A coating is judged by whether release stays under the limit after two years of normal use, not by what the surface looks like on day one. See our pages on gold plated, gold filled and vermeil and PVD coating.

What EN 1811 is

A 2010 study abstract (PMID 20536475, Contact Dermatitis) describes EN 1811 as “a European standard reference method developed by the European Committee for Standardization (CEN)”, fine-tuned to estimate nickel release around the limit value of the EU Nickel Directive for products meant for direct and prolonged skin contact. The same abstract says assessments under EN 1811 are expensive to perform, time consuming and may destroy the test item. That is why a cheap screening test is attractive, and why its accuracy matters. We read the standard only as described there, so we do not give its procedure.

What a DMG spot test is, and what studies found

A DMG spot test is a quick screen that gives a yes or no on nickel at the point where it is applied. It does not report a release rate in micrograms per square centimetre per week, so it cannot show whether an item is above or below the EU limits. Four study abstracts speak to how well it performs.

2010, San Francisco earrings (PMID 20536475). The authors ran DMG spot tests, EN 1811 chemical analysis and X-ray fluorescence on 96 metal components from recently purchased earrings. Against EN 1811 results, they report a sensitivity of 59.3% and a specificity of 97.5%. In plain terms, the test rarely flagged items the reference method did not, but it missed a substantial share of the items the reference method did flag. The authors conclude the test has high specificity but modest sensitivity, and “may serve well for screening purposes”. They add that past exposure studies may have underestimated nickel release from consumer items.

1998, Helsinki earrings (PMID 9926431, Science of the Total Environment). A city environment centre tested 66 piercing-earring objects (30 pairs) with the DMG test, done two ways with and without ethanol and heat pre-handling. All were negative. Atomic absorption spectrometry found 25 of the 66 (38%) released 0.05% or more nickel. After artificial sweat treatment, 11 objects released more than 0.5 micrograms per square centimetre per week by that method, and 9 objects (14%) were positive in DMG tests. The authors call the DMG test unreliable for detecting nickel release from jewelry and say consumer-item quality control should be done by laboratories with quantitative methods.

1987, 54 metal objects (PMID 3665734, Dermatosen in Beruf und Umwelt). The stick test was evaluated on 54 randomly bought metal objects designed for prolonged skin contact and on 15 alloys of known composition, against surface analysis and release into synthetic sweat. It found the test “will identify most nickel containing alloys” but with “important exceptions”, where it recommends provocative user tests or patch tests with the suspected alloy.

The studies differ in method, year and sample, so we do not average them. They agree on direction: a positive is informative and a negative is not conclusive. One caution runs the other way too. The 2010 sensitivity and specificity are measured against the EN 1811 result, so they tell you about that comparison and not about any single item you hold.

What this means for jewelry shopping

• A negative home test is not evidence an item meets the EU limits. Of the sources we read, none says a negative test confirms low release.
• A maker’s “nickel-free” or “hypoallergenic” wording is a claim. Our page on what hypoallergenic jewelry means goes through how that word is used. Ask whether a maker reports release testing against the EU limits, and which standard was used.
• Material grade carries information a spot test does not. See surgical steel, 316L and 304, titanium grades, gold karats and nickel, sterling silver and palladium in white gold. Even then, grade names do not give a release rate.
• Plated pieces can change over time. Our guides on rhodium plating and why jewelry turns skin green cover what wear does to a finish.
• If you pierce a new ear or have diagnosed nickel allergy, the 0.2 limit above is the stricter one in the EU text. Our roundups of hypoallergenic earrings for piercing, nickel free earrings and hypoallergenic jewelry list makers’ published material claims, not test results.

The US position

CPSC’s jewelry FAQ (retrieved 2026-11-14) says there are “no mandatory federal requirements specifically for jewelry”. It points to industry consensus standards as best practice: ASTM F2999 for adult jewelry and ASTM F2923 for children’s jewelry. It adds that children’s jewelry must meet the requirements for children’s products, such as total lead content and lead in paint and similar surface coatings. The passages we read do not mention nickel, so this page cannot say what the ASTM standards say about it, or whether any US rule sets a nickel release limit.

A plain line

This page is not medical advice. A spot test cannot diagnose an allergy or tell you whether you will react. A review abstract cited above says even the EU level is not safe for every nickel-sensitive person. If you suspect nickel allergy, ask a dermatologist or an allergy or dermatology society about patch testing.

What we don’t fully know

We did not find recent studies of how current kits perform, did not read any kit’s instructions, and did not read EN 1811 itself. The remaining limits are in the unknowns box on this page.