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
Tuesday, 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
0.3 mL aliquot of 24 hour urine collection
Storage Temperature
Refrigerated preferred, ambient and frozen acceptable
Additional Information

Test sent to Mayo Medical Laboratories.

CPT Code
Fee Code