Consumer leather exposure: an unrecognized cause of cobalt sensitization

Abstract

Cobalt is used in the so-called pre-metallized dyeing of leather products. Repeated studies have found high levels of cobalt sensitization, but not nickel sensitization, in patients with foot dermatitis. We raise the possibility that cobalt may be widely released from leather items, and advise dermatologists to consider this in patients with positive cobalt patch test reactions.

Contact Sensitization in Children: A Retrospective Study of 2,614 Children from a Single Center

“…Of 291 patients with a positive patch test to cobalt, 135 (46.4%) also had a positive reaction to nickel, confirming that contact sensitization to cobalt is often but not always associated with contact sensitization to nickel and challenging the traditional view of cobalt as a concomitant allergen . Contact sensitization to cobalt in children may result not only from jewelry, but also from toys and leather footwear , as underlined by the association with foot dermatitis.…”

Association between cobalt allergy and dermatitis caused by leather articles – a questionnaire study

“…In 2010, isolated cobalt allergy was reported to be significantly more frequent among female textile and leather workers in a study by Rui et al . A recent study by Thyssen et al , from 2013, established the relevance of leather as a source of cobalt from a sample of a patient's couch; this resulted in a smaller market survey of 14 leather samples from the Danish furniture market, all of which were negative when examined with the cobalt spot test . In market surveys, only a small proportion of items releasing cobalt were found when cobalt release from jewellery, hair clasps, mobile phones and non‐professional work tools was examined .…”

Occupational exposure to metallic cobalt in a baker

“…A cobalt spot test was recently developed . It has proven to be a useful tool in the diagnostic work‐up of patients suspected of having allergic cobalt dermatitis . Here, we report a baker who developed allergic cobalt dermatitis following occupational exposure to baking sheets.…”