Last updated : November 18, 2024
The Department of Transportation (DOT) requires that all safety-sensitive employees submit to pre-employment drug testing as well as random, reasonable suspicion, and post-accident drug testing. The procedure is well documented from start to finish to lessen the chance of error. Likewise, laboratories, operating under strict protocols, have specific drug cutoff levels set to lessen the chance of error, as well.
The levels work toward protecting those being tested from obtaining a false positive result. There are documented cases of this happening. Before the cutoff levels were changed to alleviate the problem, poppy seeds were notorious for causing people to test positive for opiates. Even after the change, the debate whether or not they can cause a false positive continues.
Some over-the-counter medications can cause false positive drug tests too. Cold medications with codeine have triggered false positive results for morphine. Even Ibuprofen taken in any form can sometimes cause false positive marijuana use.
What are cut-off levels?
Laboratories that process drug tests for the DOT must be certified by the Substance Abuse and Mental Health Services Administration (SAMHSA). These laboratories follow DOT-mandated guidelines defining the amounts of drugs in your system that trigger a positive result for a specific drug. Therefore, if the level has a lower metabolite count than the level set, the test is negative. This eliminates the chance that trace amounts in the body, such as those caused by poppy seeds or ibuprofen, don’t cause false positive drug test results.
A specific drug test panel is added to create the requested drug test. While free to test for any drug, many employers of the general workforce use the DOT drug test as an example to go by and test for the same drugs.
They are:
- Amphetamines and methamphetamines
- Cocaine
- Marijuana
- Opioids, including the synthetic opioids oxycontin, oxycodone, hydrocodone, and hydromorphone
- Phencyclidine (PCP)
DOT Drug Testing Mandates Changing
The DOT enforces the Omnibus Transportation Employee Testing Act of 1991 which includes drug testing requirements for all agencies under its regulation. Until February 2022, the urine test was the only approved employee drug testing method. That’s when the department announced its final ruling allowing employers to use the oral fluid drug test. Proposed changed at the beginning of 2024 weren’t followed through with due to negative comments received. However, even if changes were implemented, no laboratories are certified to process the tests yet—and we need at least two.
Whether or not an employer uses oral fluid testing is entirely up to them. The urine and oral fluids tests may be interspersed as seen fit. Say an employee suffers from shy bladder syndrome, then, an oral fluid test could be used instead.
The specifics
Below is a chart of the specific cutoff levels for each drug contained on the DOT drug test.
| Initial Test Analyte | Initial test cutoff | Confirmatory analyte | Confirmatory test cutoff concentration | |
| 1 | Marijuana Metabolites (THCA) | 50 ng/m | THCA | 15 ng/mL |
| 2 | Cocaine Metabolite (Benzoylecgonine) | 150 ng/mL | Benzoylecgonine | 100 ng/mL |
| 3 | Phencyclidine (PCP) | 25 ng/mL | Phencyclidine (PCP) | 25 ng/mL |
| 4 | Amphetamine | |||
| Amphetamine | 500 ng/m | Amphetamine | 250 ng/mL | |
| Methamphetamine | 500 ng/mL | Methamphetamine | 250 ng/mL | |
| MDMA/MDA | 500 ng/mL | MDMA/MDA | 250 ng/mL | |
| 5 | Opioids | |||
| Codeine/Morphine | 2000 ng/mL | Codeine/Morphine | 2000 ng/mL | |
| 6-Acetylmorphine (6AM or Heroin) | 10 ng/mL | 6-Acetylmorphine (6AM or Heroin) | 10 ng/mL | |
| Hydrocodone | 300 ng/mL | Hydrocodone | 100 ng/mL | |
| Hydromorphone | 300 ng/mL | Oxymorphone | 100 ng/mL | |
| Oxymorphone | 100 ng/mL | Oxymorphone | 100 ng/mL | |
| Oxycodone | 100 ng/mL | Oxycodone | 100 ng/mL |
The five panel drug test is constructed as mandated in DOT regulations 49 CFR part 40, Section 87.
