title: Chromium(III) and chromium(VI) release from leather during 8 months of simulated use.
abstract: BACKGROUND
  Chromium (Cr) release from Cr-tanned leather articles is a major cause of Cr contact dermatitis. It has been suggested that Cr(VI) release from leather is not necessarily an intrinsic property of the leather, but is strongly dependent on environmental conditions.
  
  
  OBJECTIVE
  To test this hypothesis for long-term (8 months) simulated use.
  
  
  METHODS
  The release of total Cr and Cr(VI) from Cr-tanned, unfinished leather was analysed in subsequent phosphate buffer (pH 8.0) immersions for a period of 7.5 months. The effect of combined ultraviolet treatment and alkaline solution (pH 12.1) was tested. Dry storage [20% relative humidity (RH)] was maintained between immersions. Atomic absorption spectroscopy, X-ray fluorescence and diphenylcarbazide tests were used.
  
  
  RESULTS
  Cr(VI) release was dependent on previous dry storage or alkaline treatment, but not on duration or number of previous immersions. Cr(III) release decreased with time. Fifty-two percent of the total Cr released during the last immersion period was Cr(VI). Cr(VI) release exceeded 9 mg/kg in all immersion periods except in the first 10-day immersion (2.6 mg/kg).
  
  
  CONCLUSIONS
  Cr(VI) release is primarily determined by environmental factors (RH prior to immersion, solution pH, and antioxidant content). The RH should be kept low prior to testing Cr(VI) release from leather.
authors.affiliation: Division of Surface and Corrosion Science, Department of Chemistry, School of Chemical Science and Engineering, KTH Royal Institute of Technology, 100 44, Stockholm, Sweden.|Institute of Environmental Medicine, Karolinska Institutet, 171 77, Stockholm, Sweden.
authors.forename: Yolanda S
authors.identifier: http://orcid.org/0000-0003-2145-3650
authors.initials: YS
authors.lastname: Hedberg
authors.affiliation: Institute of Environmental Medicine, Karolinska Institutet, 171 77, Stockholm, Sweden.
authors.forename: Carola
authors.initials: C
authors.lastname: Lidén
mesh_terms: D000975:Antioxidants; D002857:Chromium / Q000009:adverse effects / Q000032:analysis*; D017449:Dermatitis, Allergic Contact / Q000209:etiology; D004160:Diphenylcarbazide; D006801:Humans; D006813:Humidity; D006863:Hydrogen-Ion Concentration; D007202:Indicators and Reagents; D013052:Spectrometry, X-Ray Emission; D013054:Spectrophotometry, Atomic; D013633:Tanning
chemical_list: D000975:Antioxidants; D007202:Indicators and Reagents; D002857:Chromium; C074702:chromium hexavalent ion; D004160:Diphenylcarbazide
keywords: alkaline environment; allergic contact dermatitis; chemical analysis; chromium(III); chromium(VI); humidity; leather; metals; occupational