Update Type: Reference range changed
Test Updated: 11/17/2021
Test Overview
Test Methodology

Inductively Coupled Plasma-Mass Spectrometry (ICP-MS)

Test Usage

Monitoring iodine excretion rate as an index of adequate dietary iodine intake.

Reference Range *

age 0-17 years: not established; age >=18 years: 75 - 851 mcg/24 hour.

* Reference ranges may change over time. Please refer to the original patient report when evaluating results.

Test Limitations

Administration of iodine-based contrast media and drugs containing iodine, such as amiodarone, will yield elevated results.

Test Details
Days Set Up
Monday, Wednesday, Friday
Analytic Time

2 - 4 days

Soft Order Code
MiChart Code
Iodine 24 Hour Urine (Sendout)
  • Urinary Free Iodine
Reference Laboratory
Mayo UIOD (9549)
Special Testing
Specimen Requirements
Collection Instructions

Collect 24 hour urine specimen with no preservative. Aliquot 10 mL into a clean plastic container and refrigerate. Record total 24 hour urine volume and collection dates/times on request form. Note: if this test is used in conjunction with the (131)I Updake Test, the specimen collection should begin immediately after the dose of (131)I is given.

Alternate Specimen
Urine with 50% Acetic Acid preservative acceptable. [5/08]
Do not collect specimens from patients who have received gadolinium within the past 48 hours. Gadolinium, a material contained in some contrast media, is known to interfere with most metals tests.
Normal Volume
10 mL aliquot of 24 hour urine collection
Minimum Volume
2 mL aliquot of 24 hour urine collection
Additional Information

Test sent to Mayo Medical Laboratories.

CPT Code
Fee Code