title: Investigation on formaldehyde release from preservatives in cosmetics.
abstract: OBJECTIVE
  To understand formaldehyde residue in cosmetics, an investigation on formaldehyde release from eight preservatives (methenamine - MA, paraformaldehyde - PF, poly(p-toluenesulfonamide-co-formaldehyde) -PTSAF, quaternium-15 - QU, imidazolidinyl urea - IU, diazolidinyl urea - DU, dimethyloldimethyl hydantoin - DMDM and bronopol - BP) under various conditions was performed.
  
  
  METHODS
  The concentration of released formaldehyde was determined by high-performance liquid chromatography with photodiode array detection after derivatization with 2,4-dinitrophenylhydrazine.
  
  
  RESULTS
  The amounts of formaldehyde release were in the order of PF > DU > DMDM ≈ QU ≈ IU > MA > BP > PTSAF. The releasing amounts of formaldehyde were the highest in the presence of aqueous matrices for the releasers except QU and IU, and the releasing effect was also relative to pH. More formaldehyde was released with longer storage time and higher temperature. Furthermore, all preservatives in cosmetic matrices released fewer amounts of formaldehyde than in pure aqueous or organic matrices, and the formaldehyde-releasing amounts were also cosmetic specific.
  
  
  CONCLUSIONS
  Formaldehyde release was dependent on the matrix, pH, time and mainly temperature, and the releasing effect was also cosmetic specific.
authors.affiliation: Zhejiang Entry-Exit Inspection and Quarantine Bureau, Hangzhou, 310016, China.
authors.forename: C
authors.initials: C
authors.lastname: Lv
authors.affiliation: Zhejiang Entry-Exit Inspection and Quarantine Bureau, Hangzhou, 310016, China.
authors.forename: J
authors.initials: J
authors.lastname: Hou
authors.affiliation: Zhejiang Entry-Exit Inspection and Quarantine Bureau, Hangzhou, 310016, China.
authors.forename: W
authors.initials: W
authors.lastname: Xie
authors.affiliation: College of Material Chemistry and Chemical Engineering, Hangzhou Normal University, Hangzhou, 310036, China.
authors.forename: H
authors.initials: H
authors.lastname: Cheng
mesh_terms: D002851:Chromatography, High Pressure Liquid; D003358:Cosmetics / Q000737:chemistry*; D005557:Formaldehyde / Q000737:chemistry*; D011310:Preservatives, Pharmaceutical / Q000737:chemistry*
chemical_list: D003358:Cosmetics; D011310:Preservatives, Pharmaceutical; D005557:Formaldehyde
keywords: cosmetics; formaldehyde; formaldehyde releasers; release rule