Hide and Seek: Hidden Causes of Nickel Allergy

by Audrey Kunin, MD

Posted on | By Audrey Kunin, MD

Nickel allergy is a common reaction to minute amounts of nickel particles coming into direct contact with the skin and may include jewelry, watches, zippers, snaps and even eyeglasses. Approximately 10% of Americans have an allergy to nickel. Certain occupations result in habitual nickel exposure, which increases the risk of developing a nickel allergy. These include metal factory workers, hairdressers, tailors and restaurant workers.

Jewelry Not a Girl's Best Friend?

Because women tend to wear more jewelry, particularly costume jewelry which has a high nickel content, they are more commonly affected. Men rarely present with a nickel allergy unless developed through occupational exposure. A nickel allergy may arise at any age, and as with any form of allergy, the more often the exposure, the higher the risk for developing an allergy. As seen with other medical allergies, once a person is allergic, they are always allergic.

Eczema patients (or those with atopic dermatitis or other forms of chronic open skin rashes) are more prone to developing a nickel allergy as the nickel particles can gain better access to entering the bloodstream. Also, if nickel comes in contact with an open wound, this can act as a source of sensitization. Ear, nose and body piercings can ironically act as a major form of nickel sensitization. Use of stainless steel, medical plastic or medical titanium earrings are vital during the ear piercing process to reduce this risk.

Acting Rashly

Why does a rash form from exposure to nickel? Nickel sulfate is considered foreign by the immune system – much like the body would react to a germ. When one of these foreign substances comes into contact with the skin, the body reacts, causing a rash termed an "allergic contact dermatitis." There are many causes of allergic contact dermatitis but they share clinical similarities in the appearance of the rash. Inflammation leads to itching, redness, rough scaly areas, cracking and perhaps weeping or blistered skin.

Repeat insults result in repeat flare-ups. This explains why the earlobes for instance may only develop an itchy rash periodically when certain high-risk earrings are worn versus continuous daily problems with a wedding ring.

The Finer Things in Life

Yes, while it is true that you may own "good" jewelry, not the costume variety, all metallic jewelry still contains some small percentage of nickel. Purity is a pretense. There simply is no such thing as pure gold jewelry. While no one is surprised if they break out to their $9.95 pair of earrings, they are horrified when it happens with the real thing. The longer that you wear a good piece of jewelry, the more the microscopic "good" metal molecules are worn away, exposing the nickel molecules to the skin. This is how you can suddenly become allergic to an object you’ve worn "forever."

For most, nickel sulfate contact dermatitis is confined to objects with a high concentration of nickel, associated with costume jewelry or watchbands. For finer jewelry, prolonged contact with the object is typically required to cause the rash. Gold and sterling silver molecules invisibly wear away over time allowing nickel to come into contact with the skin. Twenty-four karat gold jewelry may have a hardener added due to the softness of the gold, making it more suspect than its 14 and 18K counterparts. Gold plating with 24K is less likely to result in this as it does not require the hardeners that a solid ring or bracelet may require.

Hidden Treasure

Nickel sulfate may be a hidden treasure in your most commonly used products, creams and even medications. Instances of cross-reactions to molecularly related products not truly containing nickel may also occur. If a patch test for nickel allergy is positive, don't overlook these potential sources:

•  Non-U.S. Coins (The 1- and 2-euro coins have recently made headlines as concern gathers about its potential role in causing nickel allergy.)

•  Green Felt Dye (such as that used on pool tables)

•  Machine oils used to cut or grind

•  Some eye cosmetics

•  Chromium and cobalt

•  Canned foods such as tuna (the nickel leaches from the can into the food)

•  Broccoli and chocolate, nickel-rich foods

•  Antabuse (disulfuram, a prescription oral medication)

•  Alkaline batteries

•  Cell phones

•  Bra clasps, snaps, zippers and metal buttons

•  Paper clips

•  Eyeglass frames

Surprised to find dental fillings failed to make the list of potential nickel sources? Neither did surgical staples, wires or orthopedic implants. It is extremely rare for stainless steel instruments and alloys used in dentistry to cause nickel dermatitis. Reasons include minimal nickel concentrations and potentially brief contact time, such as with a surgical instrument. Titanium and even medical plastic have been introduced into the medical marketplace as well to avoid the risk of exposure to nickel.

Testing, Testing, 1-2-3

Repeat performances of a nickel allergy often lead patients to seek dermatology advice. Patient work-up frequently includes the simple, painless and effective T.R.U.E. Test Patch. Testing identifies 23 of the most common causes of a contact dermatitis including nickel sulfate. While it's ideal to learn the source of an allergy, avoidance may be more difficult, particularly when nickel is found in such a wide variety of inanimate objects found in daily life. Nickel is contained in a wide variety of places making its detection a challenge. Just imagine nickel lurking in zippers, snaps, pens, jewelry, tools, eating utensils, door knobs and even certain eye creams or medications. The list is endless. It's important to know that despite its name, the US nickel (and all other US coins) no longer contains nickel. United States coins are made with zinc and copper.

Reduce Your Risk

There are several things you can do to try to continue wearing that wedding band and prevent exposure to other sources of nickel as well.

Try a mild topical steroid cream under the area when needed. This is tricky, as in the case of a potent topical steroid used "under occlusion" (something is placed on top of the steroid cream layer, such as tape, or in this case a ring), the steroid is driven deeper into the skin and over time can thin the skin. Using a plain 1% over-the-counter hydrocortisone cream is an emergency method (not to be used long-term) of reducing the inflammation. Oral antihistamines also help rapidly reduce discomfort.

Consider using an at-home nickel detection system. Several are on the market and help find hidden sources of nickel in items from jewelry to everyday gadgets.

Simply apply a coat of the Nickel Guard to provide a barrier protection between your jewelry and your skin. Nickel Guard may be applied to the surface of your ring or any other jewelry. This product is safe and easy and will not harm even your most valuable items.

Keep your skin dry where the metal is going to contact you. Placing your hands into a sink-full of water allows the metal ions to be better absorbed into the skin.

Wear a good layer of protective, bland moisturizing cream. The better the barrier between you and the metal, the less likely the reaction will be bothersome. The non-acidic nature helps prevent chemical reactions with the metal which then allows nickel particles to be released from the object of concern.

Consider electroplating sentimental or really good pieces of jewelry. Take your ring, etc., back to the jeweler and see if a new layer of "good" metal can be applied to the contact surface. This prevents leaching of the nickel particles onto your skin, at least for a while.

Take your ring/jewelry off when you don't absolutely need to be wearing it. Diminished contact with the skin decreases the amount of allergen you are exposed to.

Stay dry. Perspiration can leach nickel particles out of the skin both by hastening the rate of wearing invisible "good" metal particles away as well as potentially chemically reacting with various metals.

In cases where the allergen is in an item that is not worn, use of vinyl gloves can help. Since both nickel allergy and latex allergy are common within those prone to eczema, I would prefer vinyl to a latex glove option. Severe nickel dermatitis in association with industrial levels of nickel-containing metals may require thicker protective work gloves in addition to thinner barrier alternatives.

Cover metal handles with plastic may provide relief for anyone finding it necessary to work with this type of equipment. To salvage current earrings, see if wearing stainless steel, titanium or medical plastic backs helps.

Short of treating a contact dermatitis with topical steroids, moisturizers and antihistamines, the best way to deal with a nickel contact dermatitis is to avoid it in the first place.

Article written by Audrey Kunin, MD
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