title: Recommendation to include formaldehyde 2.0% aqua in the European baseline patch test series.
abstract: BACKGROUND
  The currently used patch test concentration of formaldehyde (1.0% aqua; 0.30 mg/cm(2)) has been shown to fail to detect ~ 50% of contact allergies to formaldehyde.
  
  
  OBJECTIVE
  To justify the inclusion of formaldehyde 2.0% aqua (0.60 mg/cm(2)) in the European baseline patch test series.
  
  
  METHODS
  A survey of the reported frequencies of contact allergy to formaldehyde found with formaldehyde 2.0% aqua as compared with 1.0% aqua was performed. Studies that describe a standardized patch test technique for obtaining a correct dose per unit area were included. Experimental provocation tests in patients with contact allergy to formaldehyde detected only with 2.0% aqua were also surveyed.
  
  
  RESULTS
  In a multicentre study performed in 12 dermatology clinics among 3591 individuals, 3.4% reacted to 2.0%, and 1.8% reacted to 1.0% (p < 0.001). A randomized double-blind repeated open application test performed in individuals reacting only to 2.0% but not to 1.0% showed that 9 of 17 formaldehyde-allergic individuals reacted to a moisturizer that contained formaldehyde (p < 0.001).
  
  
  CONCLUSIONS
  It is recommended that formaldehyde 2.0% aqua (0.60 mg/cm(2)) should replace formaldehyde 1.0% in the European baseline series from 2014. With the Finn Chamber(®) technique, a standardized amount of 15 µl of the solution obtained by using a micropipette should be used.
authors.affiliation: Department of Occupational and Environmental Dermatology, Skåne University Hospital, Lund University, Malmö, SE-20502, Sweden.
authors.forename: Ann
authors.initials: A
authors.lastname: Pontén
authors.forename: An
authors.initials: A
authors.lastname: Goossens
authors.forename: Magnus
authors.initials: M
authors.lastname: Bruze
mesh_terms: D000485:Allergens / Q000008:administration & dosage / Q000009:adverse effects; D017449:Dermatitis, Allergic Contact / Q000175:diagnosis* / Q000209:etiology; D004305:Dose-Response Relationship, Drug; D005060:Europe; D005557:Formaldehyde / Q000008:administration & dosage / Q000009:adverse effects; D006801:Humans; D010328:Patch Tests / Q000379:methods*; D017410:Practice Guidelines as Topic; D012996:Solutions
chemical_list: D000485:Allergens; D012996:Solutions; D005557:Formaldehyde
keywords: EU legislation; allergic contact dermatitis; baseline series; contact allergy; cosmetics; dose; formaldehyde; micropipette; patch test; preservatives