title: Determination of reference concentrations of strontium in urine by inductively coupled plasma atomic emission spectrometry.
abstract: OBJECTIVE
  The aim of this study was to establish reference concentrations of urinary strontium by inductively coupled plasma atomic emission spectrometry (ICP-AES).
  
  
  METHODS
  For the determination of strontium, urine samples were collected from healthy Japanese (n=146; 115 males, 31 females; mean age, 33±9 years; age range, 18 to 58 years). The urine samples stored at or below -20°C were thawed with incubation at 40°C for 30 min and sediments were dissolved by vigorous shakings. Then, the samples were centrifuged at 3000 g for 5 min, and the supernatant was directly aspired into a P-5200-3600/1200 ICP-AES system from Hitachi Ltd., Tokyo, Japan.
  
  
  RESULTS
  A steeper increase in the S/N ratio and a good effective linearity of the calibration line was obtained at 407.771 nm in the range of 0-300 μg/L strontium standard solution. Urine samples having the same background signal as that of 18 MΩ cm ultrapure blank water, a good correspondence of the single peak pattern of the spectra, accuracy and precision of spike recovery were also confirmed. Urinary strontium concentrations showed a log-normal distribution and a geometric mean concentration of 143.9 μg/L, with 5-95% confidential interval of 40.9-505.8 μg/L.
  
  
  CONCLUSIONS
  The results of this study will be useful as guidelines for the biological monitoring of strontium in normal subjects and in individuals therapeutically or environmentally exposed to strontium.
authors: Department of Hygiene and Public Health, Osaka Medical College, 2-7 Daigakumachi, 569-8686, Takatsuki City, Osaka, Japan, usudakan@yahoo.co.jp.
authors: Kan
authors: K
authors: Usuda
authors: Koichi
authors: K
authors: Kono
authors: Satsuki
authors: S
authors: Hayashi
authors: Takashi
authors: T
authors: Kawasaki
authors: Go
authors: G
authors: Mitsui
authors: Takahiro
authors: T
authors: Shibutani
authors: Emi
authors: E
authors: Dote
authors: Kazuya
authors: K
authors: Adachi
authors: Michiko
authors: M
authors: Fujihara
authors: Yukari
authors: Y
authors: Shimbo
authors: Wei
authors: W
authors: Sun
authors: Bo
authors: B
authors: Lu
authors: Kazuo
authors: K
authors: Nakasuji