Chromium in leather footwear—risk assessment of chromium allergy and dermatitis

Abstract

Chromium-tanned leather footwear, which releases >3 ppm hexavalent Cr(VI), may pose a risk of sensitizing and eliciting allergic dermatitis. To determine the content and potential release of chromium in leather footwear and to discuss the prevention of chromium contact allergy and dermatitis. Sixty pairs of leather shoes, sandals and boots (20 children's, 20 men's, and 20 women's) were purchased in Copenhagen and examined with X-ray fluorescence spectroscopy. Chromium was extracted according to the International Standard, ISO 17075. The detection level for Cr(VI) was 3 ppm. Chromium was identified in 95% of leather footwear products, the median content being 1.7% (range 0-3.3%). No association with store category or footwear category was found. A tendency for there to be a higher chromium content in footwear with high prices was shown (p(trend) = 0.001). Cr(VI) was extracted from 44% of 18 footwear products, and, in three items, more than 10 ppm was extracted. One shoe had 62 ppm Cr(VI) extracted. Sandals seemed to be over-represented among footwear with detectable Cr(VI). Cr(III) extraction reached a median value of 152 ppm. Most leather footwear contained chromium. Cr(VI) was extracted from a high proportion of leather footwear; this poses a risk of sensitization.