Analytic Time

3 - 5 days

Soft Order Code

Test Updated:



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Find a Requisition

All specimens should be accompanied by a requisition.

Submitting Specimens

Learn about how to properly label and where to ship specimens.

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MLabs provides all the supplies necessary for the collection of specimens.

Test FAQ

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Test Overview

Test Methodology

Gas Chromatography/Flame Ionization Detection (GC-FID)

Test Usage

Assessing toxicity or monitoring possible abuse.

Reference Range

8.0 - 17.0 mcg/mL; Critical Value: 30 mcg/mL.

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

Specimen Requirements

Collection Onsite

Collect blood in a red top or green top tube.

Collection Offsite

Collect blood in a red top or green top tube. Centrifuge, aliquot serum or plasma into a plastic vial and refrigerate.

Normal Volume
2 mL serum or plasma
Minimum Volume
0.3 mL serum or plasma

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.