Nickel penetration in allergic individuals: bioavailability versus X-ray microanalysis detection.

Development of local allergic reactions after different application times with Finn Chambers was recorded in 34 nickel-sensitive patients. Biologically significant amounts of nickel seemed to penetrate the skin within a few hours, although physical penetration was minimal. Nickel was detected only in the upper keratin cell layer with an X-ray microanalysis method.