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HelpTest ID THCX Carboxy-Tetrahydrocannabinol (THC) Confirmation, Chain of Custody, Urine
Useful For
Detection and confirmation of drug abuse involving delta-9-tetrahydrocannabinol (marijuana)
Chain of custody is required whenever the results of testing could be used in a court of law. Its purpose is to protect the rights of the individual contributing the specimen by demonstrating that it was under the control of personnel involved with testing the specimen at all times; this control implies that the opportunity for specimen tampering would be limited.
Additional Tests
| Test ID | Reporting Name | Available Separately | Always Performed |
|---|---|---|---|
| COCH | Chain of Custody Processing | No | Yes |
| ADLTX | Adulterants Survey, CoC, U | Yes | Yes |
Testing Algorithm
Adulterants testing will be performed on all chain of custody urine samples as per regulatory requirements.
Method Name
Immunoassay/Gas Chromatography-Mass Spectrometry (GC-MS) Confirmation with Quantitation
Reporting Name
Carboxy-THC Confirmation, CoC, USpecimen Type
UrineContainer/Tube: Chain-of-Custody Kit (T282) containing the specimen containers, seals, and documentation required.
Specimen Volume: 20 mL
Collection Instructions: Collect specimen in the container provided, seal, and submit with the associated documentation to satisfy the legal requirements for chain-of-custody testing.
Additional Information: Submitting less than 20 mL will compromise our ability to perform all necessary testing.
Forms: Chain-of-Custody Request Form is included in the Chain-of-Custody Kit (T282). A copy of this form is also available at http://www.mayomedicallaboratories.com/it-mmfiles/chain-of-custody-request-form.pdf.
Specimen Minimum Volume
5 mL
Specimen Stability Information
| Specimen Type | Temperature | Time |
|---|---|---|
| Urine | Refrigerated (preferred) | 14 days |
| Frozen | 14 days | |
| Ambient | 72 hours |
Clinical Information
Delta-9-tetrahydrocannabinol is the active agent of the popularly abused street drug, marijuana.
Following consumption of the drug, either by inhalation or ingestion, it is metabolized to a variety of inactive chemicals, 1 of them being delta-9-tetrahydrocannabinol carboxylic acid.
The immunochemical procedure used to screen for tetrahydrocannabinol (THC) as part of IDOAU / Drug Abuse Survey, Urine is designed to cross-react with THC carboxylic acid.
In almost all medico-legal cases and in screening of employees, or when the patient adamantly denies THC use and the immunochemical test is positive, confirmation of the result by gas chromatography-mass spectrometry and EIA are required.
Chain of custody is a record of the disposition of a specimen to document who collected it, who handled it, and who performed the analysis. When a specimen is submitted in this manner, analysis will be performed in such a way that it will withstand regular court scrutiny.
Reference Values
Negative
Positives are reported with a quantitative GC-MS result.
Cutoff concentrations:
IMMUNOASSAY SCREEN
<50 ng/mL
THC CARBOXYLIC ACID BY GC-MS
<3 ng/mL
Cautions
No significant cautionary statements
Day(s) Performed
Monday through Friday
Report Available
2 daysPerforming Laboratory
Mayo Medical Laboratories in Rochester
Test Classification
This test was developed and its performance characteristics determined by Mayo Clinic in a manner consistent with CLIA requirements. This test has not been cleared or approved by the U.S. Food and Drug Administration.CPT Code Information
80349
G0480 (if appropriate)