This Certified Reference Material (CRM) is intended for use in the quality assurance of the analysis of arsenic species and other selected trace elements in urine. One unit of NIES CRM No.18 Human Urine consists of two bottles, each bottle containing freeze-dried urine corresponding to approximately 10 ml.
The starting material for this CRM was a composite stock of urine collected from non-occupationally-exposed Japanese males. The urine stock was filtered through membrane filters (5 μm and 0.45 μm).
Portions (10.00±0.05 g) of the filtered urine were dispensed into 950 glass bottles. The urine was then freeze-dried. Each bottle was sealed with a Teflon-lined silicone cap with aluminum closures.
keywords: Biological material, Body fluid, Urine, Speciation analysis, Arsenic speciation