title: Patch testing with the textile dyes Disperse Orange 1 and Disperse Yellow 3 and some of their potential metabolites, and simultaneous reactions to para-amino compounds.
abstract: BACKGROUND
  It is known that, in vitro, human skin bacteria are able to split disperse azo dyes into the corresponding aromatic amines, some of which are sensitizers in the local lymph node assay. We hypothesize that the molecules of disperse dyes migrate onto the skin while garments are worn, and are metabolized and degraded by commensal skin bacteria. These molecules penetrate the skin and induce sensitization.
  
  
  OBJECTIVE
  To evaluate the elicitation capacities of the possible azo-degradation products of the selected azo disperse dyes in patients allergic to them and to compare it with the elicitation capacities of other para-compounds.
  
  
  METHODS
  Ten patients allergic to Disperse Yellow 3 (DY3) and/or Disperse Orange 1 (DO1) were patch tested with a dilution series of the purified dyes 4-nitroaniline and p-aminodiphenylamine in concentrations equimolar to those of purified DO1 in the dilution series, as well as 4-aminoacetanilide and 2-amino-p-cresol in concentrations equimolar to those of purified DY3 in the dilution series. Results. Three patterns of patch test reactions could be seen. The 6 patients who were positive to DO1 and DY3 also reacted to p-aminodiphenylamine and 2-amino-p-cresol. Two patients were positive to DO1 only, and both reacted to p-aminodiphenylamine, but to neither 4-aminoacetanilide or 2-amino-p-cresol. Two patients did not react to DO1 or DY3 on this occasion.
  
  
  CONCLUSIONS
  We show that it is possible that the major sensitizers in contact allergy to DO1 and DY3 are their metabolites, p-aminodiphenylamine and 2-amino-p-cresol, respectively, which might be formed by the azoreductase pathway of skin bacteria.
authors.affiliation: Vilnius University Antakalnis Hospital Allergy Centre, 10200 Vilnius, Lithuania.
authors.forename: Laura
authors.initials: L
authors.lastname: Malinauskiene
authors.forename: Erik
authors.initials: E
authors.lastname: Zimerson
authors.forename: Magnus
authors.initials: M
authors.lastname: Bruze
authors.forename: Kristina
authors.initials: K
authors.lastname: Ryberg
authors.forename: Marlene
authors.initials: M
authors.lastname: Isaksson
mesh_terms: D015081:2-Naphthylamine / Q000031:analogs & derivatives / Q000378:metabolism; D000083:Acetanilides / Q000378:metabolism; D000328:Adult; D000368:Aged; D000814:Aniline Compounds / Q000378:metabolism; D001391:Azo Compounds / Q000009:adverse effects* / Q000737:chemistry / Q000378:metabolism; D003020:Clothing / Q000009:adverse effects; D004396:Coloring Agents / Q000009:adverse effects* / Q000378:metabolism; D003408:Cresols / Q000378:metabolism; D017449:Dermatitis, Allergic Contact / Q000209:etiology* / Q000378:metabolism*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D015394:Molecular Structure; D010328:Patch Tests / Q000379:methods; D010655:Phenylenediamines / Q000378:metabolism; D012867:Skin / Q000382:microbiology; D012869:Skin Absorption; D055815:Young Adult
chemical_list: D000083:Acetanilides; D000814:Aniline Compounds; D001391:Azo Compounds; D004396:Coloring Agents; D003408:Cresols; D010655:Phenylenediamines; C053264:black rubber; C024957:Dispersion Yellow 3; C556349:Disperse Orange 1; C019498:4-nitroaniline; C073225:2-amino-4-methylphenol; D015081:2-Naphthylamine; C519644:4-aminoacetanilide; C029728:4-phenylenediamine