title: [Development of the certified reference material of mercury in lyophilized human urine].
abstract: OBJECTIVE
  To develop the certified reference material of mercury in lyophilized human urine.
  
  
  METHODS
  Human urine samples from normal level mercury districts were filtered, homogenized, dispensed, lyophilized and radio-sterilized. Homogeneity test, stability inspection and certification were conducted using a atom fluorescence spectrophotometric method. The physical and chemical stability of the certified reference material were assessed for 18 months. The certified values are based on analysis made by three independent laboratories.
  
  
  RESULTS
  The certified values are as follows: low level was (35.6 ± 2.1) µg/L, high level was (50.5 ± 3.0) µg/L.
  
  
  CONCLUSIONS
  The certified reference material of mercury in lyophilized human urine in this research reached the national certified reference material requirements and could be used for the quality control.
authors.affiliation: National Institute of Occupational Health and Poison Control, Chinese Center for Disease Control and Prevention, Beijing 100050, China.
authors.forename: Wei
authors.initials: W
authors.lastname: Zhao
authors.forename: Fu-gang
authors.initials: FG
authors.lastname: Zhang
authors.forename: Hui-fang
authors.initials: HF
authors.lastname: DU
authors.forename: Ya-juan
authors.initials: YJ
authors.lastname: Pan
authors.forename: Hui-fang
authors.initials: HF
authors.lastname: Yan
mesh_terms: D005612:Freeze Drying / Q000592:standards*; D006801:Humans; D008628:Mercury / Q000652:urine*; D012015:Reference Standards; D013050:Spectrometry, Fluorescence; D016482:Urinalysis / Q000592:standards*
chemical_list: D008628:Mercury