Urinalysis for Special Populations

In order to distinguish between exposure to uranium from natural sources and anthropogenic origins, the isotopic composition of uranium must be determined. Such a method using sector field ICPMS for measurement of and 

236U/238U in small-volume urine samples was developed and validated (Amason et al. 2013). The woik placed special emphasis on the cleanliness of all reaction vessels used in the process, on the purity of all reagents, and on the low background contribution from the chromatographic resins used for separation and preconcentration of 

An isotope dilution method with an ICPQMS equipped with direct reaction cell (DRC) to remove interferences from polyatomic ions was described (Kimnan et al. 2009). A nebulizer suitable for high solids introduction was used for measurement of urine samples that were diluted fivefold with 10% nitric acid. Isotope ratios were precisely determined for urine sample that contained 54 ng L . A three-stage rinsing procedure was run between samples to minimize salt deposition, memory effects, and instrumental drift. 

Accurate and sensitive determination of the j 235pj/238u ratios in human 

FIGURE 4.14 236U/238U expressed as a function of ratio for a subset of patient 

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