Contact Dermatitis • Original Article COD Contact Dermatitis No skin reactions to mineral powders in nickel-sensitive subjects Marie Lod ´ en 1 , Gert Nilsson 2 , Masomeh Parvardeh 3 , Kristina Neimert Carne 4 and Mats Berg 5 1 Eviderm Institute AB, 17077 Solna, Sweden, 2 Wheelsbridge AB, 58937 Link ¨ oping, Sweden, 3 Department of Dermatology S ¨ ormland, M ¨ alar Hospital, 63188 Eskilstuna, Sweden, 4 Kemi-Intressen, 16902 Sundbyberg, Sweden, and 5 Dermatology Division, University of Uppsala and FoU Centre of 63188 S ¨ ormland, S¨ ormland, Sweden doi:10.1111/j.1600-0536.2012.02040.x Summary Background. Cosmetic products are known to be able to induce contact dermatitis. Contact dermatitis may also be induced by nickel, and it is estimated that up to 17% of women are allergic to nickel. Objectives. The aim of the present study was to investigate whether nickel sensitized individuals react to make-up products containing pigments with nickel as an impurity. Patients/Materials/Methods. Twenty-three individuals with a clinical history of nickel allergy and/or with positive patch test reactions to nickel were exposed to mineral make-up products and individual pigments dispersed in alkylbenzoate (50%) in small Finn Chambers  for 48 hr. The skin reactions were evaluated visually and with a non-invasive instrument that quantifies skin erythema. Results. The results showed that 74% of the included individuals showed a visible reaction to the positive control nickel sulfate, and a significant correlation was found between the visual and instrumental readings. However, none of the nickel sensitive individuals reacted to the test products. A subgroup analysis of the 50% most sensitive individuals also confirmed the absence of skin reactions to the powders. Conclusions. The bioavailability of the trace amounts of nickel in the particles was below the level needed to elicit an eczematous reaction in any of the nickel-sensitized individuals. Key words: adverse reaction; eczema; make-up; nickel; pigment; skin penetration. Cosmetic products are known to be able to induce contact dermatitis (1–3), fragrances and preservatives being the most common culprit sensitizing substances, along with weak irritants. Contact dermatitis may also be induced by nickel, which is common in women because of the wearing of earrings or other items of jewelry releasing nickel. The prevalence of metal allergy is high in the general population, and it is estimated that up to 17% of women Correspondence: Marie Lod ´ en, Eviderm Institute AB, Bergshamra All ´ e 9, 17077 Solna, Sweden. Tel: +46708285832. E-mail: marie.loden@eviderm.se Conflicts of interest: Letsfaceit Nordic AB, Sweden, sponsored the study but did not influence the study design or reporting. Marie Lod ´ en, Gert Nilsson, Masomeh Parvardeh and Mats Berg were paid consultants for the study. Gert Nilsson is the CEO of Wheelsbridge AB. Kristina Neimert Carne is employed by a distributor of some of the chemicals used in the study. Accepted for publication 19 October 2011 and 3% of men are allergic to nickel (4). Pigmented make- up products may also contain nickel and other metal allergens (5). Eyelid dermatitis has been observed among nickel allergic dermatitis patients following exposure to nickel containing mascara and eye shadow. However, an association between nickel eyelid dermatitis and nickel in make-up products remains controversial. Nickel is not added as such to make-up, but exists as an impurity among other ingredients, such as in iron oxides. The risk of adverse skin reactions to make-up products containing pigments depends on their absorption and the release of allergens and irritants to the viable skin. Make-up products that are based on particulate matters, that is, so-called ‘pure mineral make-up’, have entered the market, and such products are promoted as being suitable for people with sensitive skin, as they are marketed as ‘free from preservatives, fragrances’ etc. © 2012 John Wiley & Sons A/S 210 Contact Dermatitis, 66, 210–214