Determination of 15 Micro Rare Earth Elements in Human Urine Sample by ICP-MS

Urine samples were collected in the morning and were stored frozen at −20 ℃ until analysed. The samples were wet digested by HNO₃＋HCLO₄ before determination. The solution was directly analyzed by ICP-MS for the determination of Y, La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb and Lu in human urine with rhenium internal standard calibration. The detection limits were 0.1-2.1 ng•L^－1. Certified reference material of human hair GBW 09101a was analyzed by the described method. The analytical values of the certified reference material showed closed agreement with the reference values.