Survey of Chemical Substances in Consumer Products 112, 2011
In order to obtain softness, durability and flexibility, leather needs to be tanned. Tanning with chromium is by far the most important method of tanning within the leather industry and is used in more than 80% of the leather industry world-wide. However, several studies have indicated that leather products can release chromium as Cr(VI) and Cr(III) compounds which may cause allergic reactions and severe foot eczema.
In a recent study, the development of chromium allergy among patients with eczema was investigated from 1985 to 2007 in the region of Copenhagen in Denmark. A retrospective analysis of contact allergy to chromium in 16,228 patients was made. The frequency of chromium allergy decreased significantly from 3.6% in 1985 to 1% in 1995, but again increased significantly to 3.3% in 2007. The majority of cases were caused by leather products particularly in shoes. German studies support this tendency.
Thus, the main purpose of this study has been to clarify whether Cr(VI) and Cr(III) compounds are released from leather shoes in Denmark in an amount that constitutes a risk of causing allergic reactions.