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HelpTest Code THCX Delta-8 and Delta-9-Carboxy-Tetrahydrocannabinol (THC) Confirmation, Chain of Custody, Random, Urine
Reporting Name
Carboxy-THC Confirmation, CoC, UPerforming Laboratory
Mayo Clinic Laboratories in Rochester
Useful For
Detection and confirmation of drug use of cannabis/marijuana and to specifically identify and quantify delta-8 carboxy tetrahydrocannabinol (THC-COOH) and delta-9-THC-COOH
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 always under the control of personnel involved with testing the specimen; this control implies that the opportunity for specimen tampering would be limited.
Method Name
Immunoassay/Liquid Chromatography Tandem Mass Spectrometry (LC-MS/MS)
Ordering Guidance
This test is for situations that require the chain-of-custody process. For testing not requiring chain of custody, order THCU / Delta-8 and Delta-9-Carboxy-Tetrahydrocannabinol (THC) Confirmation, Random, Urine.
Specimen Required
Supplies: Chain of Custody Kit (T282)
Container/Tube: Chain-of-Custody Kit containing the specimen containers, seals, and required documentation.
Specimen Volume: 5 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.
Specimen Type
UrineSpecimen Minimum Volume
0.5 mL
Specimen Stability Information
| Specimen Type | Temperature | Time | Special Container |
|---|---|---|---|
| Urine | Refrigerated (preferred) | 14 days | |
| Frozen | 14 days | ||
| Ambient | 72 hours |
Reject Due To
| Gross hemolysis | OK |
| Gross icterus | Reject |
Reference Values
Not detected
Positive results are reported with a quantitative liquid chromatography tandem mass spectrometry (LC-MS/MS) result.
Cutoff concentrations:
IMMUNOASSAY SCREEN:
<50 ng/mL
DELTA-8 CARBOXY-TETRAHYDROCANNABINOL (THC) by LC-MS/MS: < 5.0 ng/mL
DELTA-9 CARBOXY-TETRAHYDROCANNABINOL (THC) by LC-MS/MS: < 5.0 ng/mL
Interpretation
The presence of delta-8 and/or delta-9 carboxy tetrahydrocannabinol (THC-COOH) in urine is a strong indicator that the patient has used cannabis/marijuana.
THC-COOH has a long half-life and can be detected in urine for more than 7 days after a single use.
Chronic use causes accumulation of THC and THC-COOH in adipose tissue, such that it is excreted into the urine for as long as 30 to 60 days from the time chronic use is halted.
Day(s) Performed
Monday through Sunday
Report Available
3 to 5 daysTest Classification
This test was developed and its performance characteristics determined by Mayo Clinic in a manner consistent with CLIA requirements. It has not been cleared or approved by the US Food and Drug Administration.CPT Code Information
80349
G0480 (if appropriate)
LOINC Code Information
| Test ID | Test Order Name | Order LOINC Value |
|---|---|---|
| THCX | Carboxy-THC Confirmation, CoC, U | 102114-6 |
| Result ID | Test Result Name | Result LOINC Value |
|---|---|---|
| 2449 | Carboxy-THC Immunoassay Screen | 19415-9 |
| 618771 | Delta-8 Carboxy-Tetrahydrocannabinol by LC-MS/MS | 20521-1 |
| 36238 | Delta-9 Carboxy-Tetrahydrocannabinol by LC-MS/MS | 20521-1 |
| 36239 | Carboxy-THC Interpretation | 69050-3 |
| 36240 | Chain of Custody | 77202-0 |
Forms
1. Chain of Custody Request is included in the Chain-of-Custody Kit (T282).
2. If not ordering electronically, complete, print, and send a Therapeutics Test Request (T831) with the specimen.
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
Testing for adulterants will be performed on all chain-of-custody urine samples per regulatory requirements.