Ordering Recommendation

Preferred test for the assessment of acute or chronic arsenic exposure. This test is able to differentiate between toxic inorganic and methylated species as well as benign organic forms. Results are reported as total inorganic, total methylated, and organic arsenic.

Mnemonic
U ARS RAND
Methodology

Quantitative High Performance Liquid Chromatography/Quantitative Inductively Coupled Plasma-Mass Spectrometry

Performed

Sun-Sat

Reported

1-5 days

New York DOH Approval Status
This test is New York DOH approved.
Specimen Required
Patient Preparation

Diet, medication, and nutritional supplements may introduce interfering substances. Patients should be encouraged to discontinue nutritional supplements, vitamins, minerals, nonessential over-the-counter medications (upon the advice of their physician), and avoid shellfish and seafood for 48 to 72 hours. High concentrations of iodine may interfere with elemental testing. Collection of urine specimens from patients receiving iodinated or gadolinium-based contrast media should be avoided for a minimum of 72 hours post-exposure. Collection from patients with impaired kidney function should be avoided for a minimum of 14 days post contrast media exposure.

Collect

Random urine.

Specimen Preparation

Transfer an 8 mL aliquot from a well-mixed collection to ARUP Trace Element-Free Transport Tubes (ARUP supply #43116), available online through eSupply using ARUP Connect or contact ARUP Client Services at (800) 522-2787. (Min: 2 mL)

Storage/Transport Temperature

Refrigerated. Also acceptable: Room temperature or frozen.

Unacceptable Conditions

Acid preserved urine. Specimens collected within 72 hours after administration of iodinated or gadolinium-based contrast media.

Remarks

Trace Elements requisition form may be required (ARUP form #32990-Barcode; #32991-No Barcode).

Stability

Ambient: 1 week; Refrigerated: 2 weeks; Frozen: 1 year

Reference Interval

Effective November 13,2017

Test Number
Components
Reference Interval
Arsenic, Urine - per volume 0-34.9 µg/L (based on Biological Exposure Index)
Arsenic, Urine-ratio to CRT 0.0-29.9 µg/g CRT
0020734 Arsenic, Fractionated, Urine
Test Number Components
Reference Interval
  Arsenic, Organic Refer to report
  Arsenic, Inorganic Refer to report
  Arsenic, Methylated Refer to report

Interpretive Data

The ACGIH Biological Exposure Index (BEI) for arsenic in urine is 35 µg/L. The ACGIH BEI is based on the sum of inorganic and methylated species. For specimens with a total arsenic concentration of 35 to 2000 µg/L, fractionation is automatically performed to determine the proportions of inorganic, methylated and organic species. It may be appropriate to request fractionation for specimens with total arsenic greater than 30 µg/gCRT despite a total arsenic concentration less than 35 µg/L. If low-level chronic poisoning is suspected, the µg/gCRT ratio may be a more sensitive indicator of arsenic exposure than the total arsenic concentration.

This test was developed and its performance characteristics determined by ARUP Laboratories. It has not been cleared or approved by the US Food and Drug Administration. This test was performed in a CLIA certified laboratory and is intended for clinical purposes.

Compliance Category

Laboratory Developed Test (LDT)

Note

If total arsenic concentration is between 35-2000 µg/L, then Arsenic, Fractionated, will be added to determine the proportion of organic, inorganic, and methylated forms. Additional charges apply.

Hotline History
N/A
CPT Codes

82175; if reflexed, add 82175

Components
Component Test Code* Component Chart Name LOINC
0020207 Creatinine, Urine - per volume 2161-8
0025001 Arsenic Urine - per volume 5586-3
0025058 Arsenic, Urine - ratio to CRT 13463-5
* Component test codes cannot be used to order tests. The information provided here is not sufficient for interface builds; for a complete test mix, please click the sidebar link to access the Interface Map.
Aliases
  • Arsenic/Creatinine Ratio, Random, Urine
  • As
  • ASU
  • Normalized Urine Arsenic
  • Normalized Urine As
Arsenic, Random Urine with Reflex to Fractionated