Test ID: ASFR
Arsenic Fractionation, 24 Hour, Urine
Secondary ID
A test code used for billing and in test definitions created prior to November 2011
NY State Approved
Indicates the status of NY State approval and if the test is orderable for NY State clients.
Useful For
Suggests clinical disorders or settings where the test may be helpful
Diagnosis of arsenic intoxication
Special Instructions and Forms
Describes specimen collection and preparation information, test algorithms, and other information pertinent to test. Also includes pertinent information and consent forms to be used when requesting a particular test
Method Name
A short description of the method used to perform the test
Liquid-Liquid Extraction/Inductively Coupled Plasma-Mass Spectrometry (ICP-MS)
Reporting Name
A shorter/abbreviated version of the Published Name for a test; an abbreviated test name
Aliases
Lists additional common names for a test, as an aid in searching
Arsenic, Inorganic Forms
Arsenic, Organic Forms
As (Arsenic)
Specimen Type
Describes the specimen type needed for testing
Specimen Required
Defines the optimal specimen. This field describes the type of specimen required to perform the test and the preferred volume to complete testing. The volume allows automated processing, fastest throughput and, when indicated, repeat or reflex testing.
Collection Container/Tube: Clean, plastic urine container with no metal cap or glued insert.
Submission Container/Tube: Plastic, 10-mL urine tube (Supply T068) or clean, plastic aliquot container with no metal cap or glued insert
Specimen Volume: 10 mL
Collection Instructions:
1. Collect urine for 24 hours.
2. No preservative. See Urine Preservatives in Special Instructions for multiple collections.
3. Patient should not eat seafood for a 48-hour period prior to start of collection.
4. See Metals Analysis-Collection and Transport in Special Instructions for complete instructions.
5. Refrigerate specimen within 4 hours of completion of 24-hour collection.
Additional Information:
1. 24-Hour volume is required.
2. High concentrations of gadolinium and iodine are known to interfere with most metals tests. If either gadolinium- or iodine-containing contrast media has been administered, a specimen should not be collected for 96 hours.
Urine Preservative Collection Options
| Ambient | Yes |
| Refrigerated | Preferred |
| Frozen | Yes |
| 6N HCl | Yes |
| 50% Acetic Acid | Yes |
| Na2CO3 | No |
| Toluene | Yes |
| 6N HNO3 | No |
| Boric Acid | No |
| Thymol | No |
Forms: If not ordering electronically, submit a General Request Form (Supply T239) with the specimen.
Specimen Minimum Volume
Defines the amount of specimen required to perform an assay once, including instrument and container dead space. Submitting the minimum specimen volume makes it impossible to repeat the test or perform confirmatory or perform reflex testing. In some situations, a minimum specimen volume may result in a QNS (quantity not sufficient) result, requiring a second specimen to be collected.
Reject Due To
Identifies specimen types and conditions that may cause the specimen to be rejected
| Hemolysis | NA |
| Lipemia | NA |
| Icterus | NA |
| Other | NA |
Specimen Stability Information
Provides a description of the temperatures required to transport a specimen to the laboratory. Alternate acceptable temperature(s) are also included.
| Specimen Type | Temperature | Time |
|---|---|---|
| Urine | Refrigerated (preferred) | 7 days |
| Ambient | 7 days | |
| Frozen | 7 days |
Clinical Information
Discusses physiology, pathophysiology, and general clinical aspects, as they relate to a laboratory test
Arsenic (As) exists in a number of different forms; some are toxic, while others are not. The toxic forms are the inorganic species of As(+3) (As-III), As(+5) (As-V), and their partially detoxified metabolites, monomethylarsine and dimethylarsine. As-III is more toxic than As-V and both are more toxic than mono- and dimethylarsine. 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 chicken that have been fed on seafood remnants may also contain the organic forms of arsenic.
Following ingestion of arsenobetaine and arsenocholine, these compounds undergo rapid renal 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.
Reference Values
Describes reference intervals and additional information for interpretation of test results. May include intervals based on age and sex when appropriate. Intervals are Mayo-derived, unless otherwise designated. If an interpretive report is provided, the reference value field will state this.
INORGANIC ARSENIC
0-24 mcg/specimen
Reference values apply to all ages.
Interpretation
Provides information to assist in interpretation of the test results
The quantitative reference range for fractionated arsenic applies only to the inorganic forms. Concentrations > or =25 mcg inorganic arsenic per specimen are considered toxic.
There is no limit to the normal range for the organic forms of arsenic, since they are not toxic and normally present after consumption of certain food types. For example, a typical finding in a urine specimen with total 24-hour excretion of arsenic of 350 mcg/24 hours is >95% is present as the organic species from a dietary source, and <5% present as the inorganic species. This would be interpreted as indicating the elevated total arsenic was due to ingestion of the nontoxic form of arsenic, usually found in food.
A normal value for blood arsenic does not exclude a finding of an elevated urine inorganic arsenic, due to the very short half-life of blood arsenic.
Cautions
Discusses conditions that may cause diagnostic confusion, including improper specimen collection and handling, inappropriate test selection, and interfering substances
Consumption of seafood before collection of a urine specimen for arsenic testing is likely to result in a report of an elevated concentration of arsenic, which can be clinically misleading.
High concentrations of gadolinium and iodine are known to interfere with most metals tests. If either gadolinium- or iodine-containing contrast media has been administered, a specimen should not be collected for 96 hours.
Nitric acid cannot be added to either the collection or aliquot container because nitric acid will cause assay failure. All specimens are tested for the presence of nitric acid prior to analysis and cannot be analyzed if nitric acid is present.
Clinical Reference
Provides recommendations for further in-depth reading of a clinical nature
Caldwell KL, Jones RL, Verdon CP, et al: Levels of urinary total and speciated arsenic in the US population: National Health and Nutrition Examination Survey 2003-2004. J Expo Sci Environ Epidemiol 2009;19:59-68
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
Test Classification
Provides information regarding the medical device classification for laboratory test kits and reagents. Tests may be classified as cleared or approved by the US Food and Drug Administration (FDA) and used per manufacturer's instructions, or as products that do not undergo full FDA review and approval, and are then labeled as an Analyte Specific Reagent (ASR), Investigation Use Only (IUO) product, or a Research Use Only (RUO) product.
CPT Code Information
Provides guidance in determining the appropriate Current Procedural Terminology (CPT) code(s) information for each test or profile. The listed CPT codes reflect Mayo Medical Laboratories interpretation of CPT coding requirements. It is the responsibility of each laboratory to determine correct CPT codes to use for billing.
82175
LOINC® Code Information
Provides guidance in determining the Logical Observation Identifiers Names and Codes (LOINC) values for the result codes returned for this test or profile.
| Result ID | Reporting Name | LOINC Code |
|---|---|---|
| 3628 | Inorganic Arsenic (Toxic) | 53838-9 |
| 3629 | Organic Arsenic (Non-Toxic) | 53839-7 |
| TM4 | Collection Duration | 13362-9 |
| VL2 | Urine Volume | 3167-4 |


