Sign in →

Epic Test Code LAB2106601 Arsenic Speciation, 24 Hour, Urine

Additional Codes

MML:SPASU


Specimen Required


Patient Preparation:

1. For the 48-hour period prior to start of collection, as well as during the collection, patient should not eat seafood.

2. High concentrations of gadolinium and iodine are known to potentially interfere with most inductively coupled plasma mass spectrometry-based metal tests. If either gadolinium- or iodine-containing contrast media has been administered, a specimen should not be collected for 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 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

Urine

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

Reject Due To

  All specimens will be evaluated at Mayo Clinic Laboratories for test suitability.

Clinical Information

Arsenic (As) exists in a number of different forms; some are toxic, while others are not. The toxic inorganic forms are arsenite (As[3+], As[III]) and arsenate (As[5+], As[V]), and their partially detoxified metabolites are monomethylarsonic acid (MMA) and dimethylarsinic acid (DMA). As(III) is more toxic than As(V), and both are more toxic than MMA and DMA. The biologic half-life of inorganic arsenic is 4 to 6 hours, while the biologic half-life of the methylated metabolites is 20 to 30 hours. Target organs of As(III)-induced effects are the heart, gastrointestinal tract, skin and other epithelial tissues, kidney, and nervous system.

 

Inorganic arsenic is carcinogenic to humans. Symptoms of chronic poisoning, called arseniasis, are mostly insidious and nonspecific. The gastrointestinal tract, skin, and central nervous system are usually involved. Nausea, epigastric pain, colic abdominal pain, diarrhea, and paresthesias of the hands and feet can occur.

 

Nontoxic, organic forms of arsenic are present in many foods. Arsenobetaine and arsenocholine are the 2 most common forms of organic arsenic found in food. The most common foods that contain significant concentrations of organic arsenic are shellfish and other predators in the seafood chain (cod, haddock, etc). Some meats, such as meats from chickens that have been fed seafood remnants, may also contain the organic forms of arsenic.

 

Following ingestion of arsenobetaine and arsenocholine, these compounds undergo rapid kidney clearance to become concentrated in the urine. Organic arsenic is completely excreted within 1 to 2 days after ingestion, and there are no residual toxic metabolites. The biologic half-life of organic arsenic is 4 to 6 hours.

 

For reporting purposes, the concentrations of the inorganic forms (As[III] and As[V]) along with the methylated forms (MMA and DMA) will be summed and reported together as 'inorganic' arsenic. This is consistent with how the biological exposure index reference range is reported.

Reference Values

TOXIC ARSENIC

<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.

Cautions

Consumption of seafood before collection of a urine specimen for arsenic testing is likely to result in a report of an elevated concentration of organic arsenic, which can be clinically misleading.

Specimen Retention Time

14 days

Performing Laboratory

Mayo Clinic Laboratories in Rochester

CPT Code Information

82175

NY State Approved

Yes

Urine Preservative Collection Options

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

Ambient

No

Refrigerate

Preferred

Frozen

OK

50% Acetic Acid

OK

Boric Acid

No

Diazolidinyl Urea

No

6M Hydrochloric Acid

OK

6M Nitric Acid

OK

Sodium Carbonate

No

Thymol

No

Toluene

No

Day(s) Performed

Monday through Friday

Report Available

3 to 5 days

Method Name

Triple-Quadrupole Inductively Coupled Plasma Mass Spectrometry (ICP-MS/MS)/Ion Chromatography Inductively Coupled Plasma Mass Spectrometry (ICP-MS)