Arsenic Fractionation, 24 Hour, Urine
Method Description Describes how the test is performed and provides a method-specific reference
Inorganic arsenic, monomethylarsonic acid (MMA), and cacodylic acid (dimethyl arsinic acid: DMA) in urine correlate with nondietary (toxic) exposure to arsenic, while arsenobetaine and arsenocholine in urine represent dietary (seafood) exposure and are of little or no significance. Arsenic acid, arsonic acid, MMA, and DMA are reduced and complexed in the presence of strong hydrochloric acid and potassium iodide and the resulting compounds extracted with toluene as iodine complexes, while nontoxic, organic arsenobetaine and arsenocholine remain in the organic fraction and are discarded. Arsenic in the extract is determined by inductively coupled plasma-mass spectrometry (ICP-MS) according to the standard operating procedure for urine total arsenic determinations.(Nixon DE, Moyer TP: Routine clinical determination of lead, arsenic, cadmium, and thallium in urine and whole blood by inductively coupled plasma mass spectrometry. Spectrochimica Acta B 1996;51:13-25)
Day(s) and Time(s) Test Performed Outlines the days and times the test is performed. This field reflects the day and time the sample must be in the testing laboratory to begin the testing process and includes any specimen preparation and processing time required before the test is performed. Some tests are listed as continuously performed, which means assays are performed several times during the day.
Monday through Friday; 11 a.m.
Analytic Time Defines the amount of time it takes the laboratory to setup and perform the test. This is defined in number of days. The shortest interval of time expressed is "same day/1 day," which means the results may be available the same day that the sample is received in the testing laboratory. One day means results are available 1 day after the sample is received in the laboratory.
Maximum Laboratory Time Defines the maximum time from specimen receipt at Mayo Medical Laboratories until the release of the test result
Specimen Retention Time Outlines the length of time after testing that a specimen is kept in the laboratory before it is discarded
Performing Laboratory Location The location of the laboratory that performs the test