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Test ID SPASU Arsenic Speciation, 24 Hour, Urine

Specimen Required

Patient Preparation:

1. Patient should not eat seafood for a 48-hour period prior to start of collection.

2. High concentrations of gadolinium and iodine are known to interfere with most metal tests. If either gadolinium- or iodine-containing contrast media has been administered, a specimen should not be collected for at least 96 hours.

Supplies: Urine Tubes, 10 mL (T068)

Collection Container/Tube: Clean, plastic urine collection container

Submission Container/Tube: Plastic, 10-mL tube or a clean, plastic aliquot container with no metal cap or glued insert

Specimen Volume: 10 mL

Collection Instructions:

1. Collect urine for 24 hours.

2. Refrigerate urine specimen within 4 hours of completion of 24-hour collection

3. See Trace Metals Analysis Specimen Collection and Transport for complete instructions.

Additional Information: For multiple collections see Urine Preservatives-Collection and Transportation for 24-Hour Urine Specimens

Useful For

Diagnosing arsenic intoxication using 24-hour urine specimens

Testing Algorithm

Total arsenic will be performed first. If the total arsenic concentration is 10 mcg/L or greater, then speciation will be performed and reported. If total arsenic is below 10 mcg/L, total arsenic will be reported as less than 10 mcg/L and speciation will not be performed.

Reporting Name

Arsenic Speciation, 24 Hr, U

Specimen Type


Specimen Minimum Volume

3 mL

Specimen Stability Information

Specimen Type Temperature Time Special Container
Urine Refrigerated (preferred) 28 days
  Frozen  28 days
  Ambient  72 hours

Reference Values


<35 mcg/L

Reference values apply to all ages.


Arsenic Speciation Interpretive Information:

The toxic arsenic concentration represents the sum of the inorganic and methylated arsenic species. The reference value for toxic arsenic is <35 mcg/L. This value is based on the American Conference of Governmental Industrial Hygienists (ACGIH) Biological Exposure Index (BEI), which does not include the non-toxic organic arsenic.

Performing Laboratory

Mayo Clinic Laboratories in Rochester

Test Classification

This test was developed, and its performance characteristics determined by Mayo Clinic in a manner consistent with CLIA requirements. This test has not been cleared or approved by the US Food and Drug Administration.

CPT Code Information


LOINC Code Information

Test ID Test Order Name Order LOINC Value
SPASU Arsenic Speciation, 24 Hr, U 96253-0


Result ID Test Result Name Result LOINC Value
609384 Inorganic Arsenic (Toxic) 41992-9
609385 Methylated Arsenic (Toxic) 96252-2
609386 Organic Arsenic (Non-Toxic) 43181-7
609406 Toxic Arsenic Concentration 96251-4
609387 Total Arsenic Concentration 21074-0

Urine Preservative Collection Options

Note: The addition of preservative or application of temperature controls must occur within 4 hours of completion of the collection.







50% Acetic Acid


Boric Acid


Diazolidinyl Urea


6M Hydrochloric Acid


6M Nitric Acid


Sodium Carbonate






Day(s) Performed

Monday through Friday

Report Available

3 to 5 days