Days Set Up
Monday - Friday
Analytic Time

1 - 4 days

MiChart Code
Iodine 24 Hour Urine (Sendout)
Soft Order Code

Test Updated:


Urinary Free Iodine

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All specimens should be accompanied by a requisition.

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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 0-15 years: not established; age >=16 years: 93 - 1125 mcg/specimen.

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

Specimen Requirements

Collection Offsite

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.

24-hour Urine Jug
Normal Volume
10 mL aliquot of 24 hour urine collection
Minimum Volume
2 mL aliquot of 24 hour urine collection

Billing Information

CPT Code
Pro Fee Code

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Our High Standard

Quality that sets us apart

As the reference laboratory division of Michigan Medicine's Department of Pathology, MLabs shares the institution's commitment to applying established quality principles to clinical laboratory testing. Like other large organizations in complex, consequential fields, we rely on an established approach to monitor quality throughout the testing process.