Chromium and cobalt in leather: A Danish market survey

Leather has been a significant source of chromium (Cr) allergy in Denmark since the 1990s. More recently, cobalt (Co) allergy has been identified in leather as a source of allergic contact dermatitis.

To measure Cr and Co levels in Danish leather goods.

A total of 87 leather samples were collected, all tanned in Europe. Handheld X-ray fluorescence (XRF) device was used to screen for the presence of Cr and Co. The 20 leather samples with the highest concentrations of Co and Co were tested using International Organization for Standardization (ISO)-standards.

XRF analysis showed Cr in 78/87 (83.9%) samples and Co in 52/87 (59.7%), with average concentrations of 41 mg/kg (range: 0.0-77 mg/kg) and 0.22 mg/kg (range: 0.0-2.9 mg/kg), respectively. ISO 10195 and 17 075-1 testing identified Cr (VI) in 7 out of 20 samples (1.4; 0.3-4.2 mg/kg), while ISO 17072-1 detected Co in 6 of 20 samples, averaging 3.95 mg/kg (range: 0.22-7.9 mg/kg).

Most leather samples contained Cr, which was expected, while Cr (VI) was detectable in seven out of twenty tested samples but only detected in one product above the regulatory limit of 3 mg/kg. A potentially significant concentration was found for Co.