Approximately 10-15% of people suffer some degree of Nickel Allergic Contact Dermatitis (NACD) caused by nickel sensitivity. Symptoms include a red itchy rash and inflamed skin in and around the piercing. People are not born with a sensitivity to nickel and can develop one at any time.
The popular trend of piercing various body parts has triggered an increase in allergic reactions to nickel.
"In the 1980s, the incidence of allergies to nickel was about 10 percent," Dr. David Cohen of the New York University School of Medicine told CNN. "By the mid-1990s, that number had increased almost 40 percent to 14.3 percent."
The problem is so prevalent the European Union has placed a nickel ban on jewellery sold there. Products intended to come into direct and prolonged contact with the skin must not release soluble nickel at a rate in excess of 0.5 microgram/cm²/ week, when tested in artificial sweat, according to standard EN 1811:1998.
Fashion necklaces, necklace-clips, earrings, bracelets, watch-straps and rings may contain nickel. Fashion jewellery tends to be less expensive and often utilises easily cast and inexpensive metals and alloys that inevitably contain nickel because of the attributes it manifests.
Stainless steel is not easily cast to produce inexpensive fashion jewellery.
Two-thirds of all nickel produced goes into stainless steel. The most common grades used are Type 304, which contains 18% chromium and 8% nickel, and the more corrosion-resistant Type 316 (18% Cr, 10% Ni, 2% Mo). The unique attributes of corrosion resistance, clean-ability, ease of fabrication, appearance, availability and, above all, the bonding of nickel within the alloy so as not to be absorbed into the bloodstream in quantities to cause a reaction means the 300 series of surgical stainless steels are the material of choice for many hygienic applications in food processing, beverage production, medicine and jewellery manufacture. The 316L grade is used extensively in findings: the posts, cups and hooks used in piercing jewellery.
The term "hypoallergenic" or "nickel free" is applied to goods whereby either nickel is not present (titanium, platinum, palladium and higher carats of yellow or rose gold - normally 14ct and higher) or nickel cannot be released at levels into the bloodstream high enough to trigger an allergic reaction.
Low carat gold and white gold (unless specifically stated to the contrary) contain nickel and are not hypoallergenic.
Hypoallergenic fashion jewellery tends to be made up of a 316L stainless or titanium post or finding used in the piercing with a cast substrate plated in a nickel free plating most commonly rhodium or possibly platinum or a high carat gold (normally 22ct).
Acute sufferers from hypo-allergy are unlikely to react to jewellery constructed with this type of integrity.
View Euro hypoallergenic earrings.