title: Development of a Certified Reference Material (NMIJ CRM 7203-a) for Elemental Analysis of Tap Water.
abstract: A certified reference material (CRM), NMIJ CRM 7203-a, was developed for the elemental analysis of tap water. At least two independent analytical methods were applied to characterize the certified value of each element. The elements certified in the present CRM were as follows: Al, As, B, Ca, Cd, Cr, Cu, Fe, K, Mg, Mn, Mo, Na, Ni, Pb, Rb, Sb, Se, Sr, and Zn. The certified value for each element was given as the (property value ± expanded uncertainty), with a coverage factor of 2 for the expanded uncertainty. The expanded uncertainties were estimated while considering the contribution of the analytical methods, the method-to-method variance, the sample homogeneity, the long-term stability, and the concentrations of the standard solutions for calibration. The concentration of Hg (0.39 μg kg-1) was given as the information value, since loss of Hg was observed when the sample was stored at room temperature and exposed to light. The certified values of selected elements were confirmed by a co-analysis carried out independently by the NMIJ (Japan) and the KRISS (Korea).
authors.affiliation: National Metrology Institute of Japan (NMIJ), National Institute of Advanced Industrial Science and Technology (AIST).
authors.forename: Yanbei
authors.initials: Y
authors.lastname: Zhu
authors.forename: Tomohiro
authors.initials: T
authors.lastname: Narukawa
authors.forename: Kazumi
authors.initials: K
authors.lastname: Inagaki
authors.forename: Shin-Ichi
authors.initials: SI
authors.lastname: Miyashita
authors.forename: Takayoshi
authors.initials: T
authors.lastname: Kuroiwa
authors.forename: Tomoko
authors.initials: T
authors.lastname: Ariga
authors.forename: Izumi
authors.initials: I
authors.lastname: Kudo
authors.forename: Masae
authors.initials: M
authors.lastname: Koguchi
authors.forename: Sung Woo
authors.initials: SW
authors.lastname: Heo
authors.forename: Jung Ki
authors.initials: JK
authors.lastname: Suh
authors.forename: Kyoung-Seok
authors.initials: KS
authors.lastname: Lee
authors.forename: Yong-Hyeon
authors.initials: YH
authors.lastname: Yim
authors.forename: Youngran
authors.initials: Y
authors.lastname: Lim
mesh_terms: D060766:Drinking Water / Q000032:analysis* / Q000592:standards; D007564:Japan; D013058:Mass Spectrometry / Q000592:standards; D012015:Reference Standards; D056910:Republic of Korea; D014131:Trace Elements / Q000032:analysis* / Q000592:standards
chemical_list: D060766:Drinking Water; D014131:Trace Elements