DOT drug test cutoff levels are the concentration thresholds that determine whether a test result is reported as positive. Below the cutoff, the result is negative — no violation, no further review. At or above the cutoff, the result triggers confirmation testing and MRO review. Understanding these levels matters both for employers managing testing programs and for drivers who want to understand what a positive actually means.
Every DOT drug test uses a two-stage process at the SAMHSA-certified laboratory. The first stage is an immunoassay screening test. This is a rapid, high-throughput test that identifies specimens likely to contain drugs at or above the screening cutoff. If the screening result is below the cutoff, the specimen is reported as negative and no further testing happens.
If the screening result is at or above the cutoff — or if the specimen shows signs of adulteration or substitution — the lab proceeds to confirmation testing using gas chromatography/mass spectrometry (GC/MS) or, for some substances, liquid chromatography-tandem mass spectrometry (LC-MS/MS). The confirmation test uses different, typically lower cutoff levels and identifies the specific compound and exact concentration. A result at or above the confirmation cutoff is a confirmed positive. The confirmation result is what the MRO uses to make the final determination.
The following cutoff levels are established in 49 CFR Part 40 (as amended through the most recent revisions):
Marijuana (THC-COOH)
Initial screening cutoff: 50 ng/mL
Confirmation cutoff: 15 ng/mL
Note: The confirmation cutoff is significantly lower than the initial screening cutoff. A specimen that screens at exactly 50 ng/mL for THC-COOH may confirm well below 15 ng/mL — in which case it reports as negative. This discrepancy between screening and confirmation is intentional and explains why not every non-negative screen leads to a confirmed positive.
Cocaine (Benzoylecgonine)
Initial screening cutoff: 150 ng/mL
Confirmation cutoff: 100 ng/mL
Opiates — Codeine and Morphine
Initial screening cutoff: 2,000 ng/mL
Confirmation cutoff: 2,000 ng/mL for codeine
Confirmation cutoff: 2,000 ng/mL for morphine
Note: The opiate initial screening cutoff was raised from 300 ng/mL to 2,000 ng/mL in 1998 specifically to reduce false positives from poppy seed consumption. Eating a poppy seed bagel no longer triggers a positive DOT drug test — at least not at these levels.
Heroin (6-Acetylmorphine)
Initial screening: Positive morphine result triggers additional GC/MS testing
Confirmation cutoff: 10 ng/mL
Note: 6-AM is a unique metabolite of heroin not produced by other opiates. A positive 6-AM result at or above 10 ng/mL is definitive evidence of heroin use — it cannot be explained by prescription opiates or poppy seeds.
Amphetamines and Methamphetamine
Initial screening cutoff: 500 ng/mL
Confirmation cutoff: 250 ng/mL for amphetamine
Confirmation cutoff: 250 ng/mL for methamphetamine
Note: A confirmed methamphetamine positive also requires amphetamine to be present at or above 100 ng/mL. This prevents false positives from certain legal medications that metabolize to methamphetamine.
MDMA (Ecstasy) and MDA
Initial screening cutoff: 500 ng/mL
Confirmation cutoff: 500 ng/mL for MDMA
Confirmation cutoff: 500 ng/mL for MDA
Phencyclidine (PCP)
Initial screening cutoff: 25 ng/mL
Confirmation cutoff: 25 ng/mL
Cutoff levels exist because drug metabolites can appear in urine from sources other than intentional drug use. The question the cutoffs try to answer: at what concentration level can we reasonably conclude the person used the drug, rather than being passively exposed?
Secondhand marijuana smoke is the classic example. Being in a room where others are smoking marijuana can result in trace amounts of THC metabolites in your urine. The 50 ng/mL initial screening cutoff and 15 ng/mL confirmation cutoff were set based on research showing that passive exposure under normal conditions won't produce urine concentrations above those levels. Only active smoking produces concentrations that exceed the cutoffs.
The same logic applies to the opiate cutoffs. The reason the codeine/morphine initial cutoff is 2,000 ng/mL — much higher than you might expect — is to exclude positive results from poppy seed consumption, which can produce measurable morphine concentrations at lower cutoffs.
Cutoff levels determine whether a result is positive at the time of testing. They don't tell you when a substance was used. The question of how long a drug stays detectable depends on metabolic rate, frequency of use, body composition, hydration, and other factors that vary significantly between individuals.
General detection windows (for occasional users at DOT cutoff levels):
These are approximations. Individual variation is significant. A driver who used marijuana three weeks before a test might be below the 15 ng/mL confirmation cutoff; another driver with different metabolism might still be above it. Cutoff levels don't answer the timing question — only the concentration question at the moment of collection.
A laboratory result isn't a final DOT drug test result. It's input for the MRO's review. Even a confirmed positive from the lab — a result that meets or exceeds the confirmation cutoff — can be reported as negative by the MRO if there's a legitimate medical explanation.
A driver taking legally prescribed codeine for post-surgical pain, who produces a urine specimen that comes back at 3,000 ng/mL for codeine and 2,800 ng/mL for morphine — those are confirmed positives from the lab's perspective. But the MRO, reviewing the driver's prescription documentation and medical history, might report that result as negative if the medication and dosing are consistent with the positive result. The MRO is the safeguard against false positives from legitimate medication use.
What the MRO cannot do: report a positive as negative because the driver claims they were passively exposed, because the driver disagrees with the result, or because the employer is in a difficult position. The MRO's authority to report a negative is limited to documented medical explanations. "I didn't do it" isn't one.
BBB Mobile DOT Drug Test provides FMCSA-compliant drug testing throughout Utah. Mobile, on-site collection at your location. $100 per DOT drug test. SAMHSA-certified lab, licensed MRO review included.
Call (435) 395-1459 or email info@bbbmobiledotdrugtest.com. Serving Park City, Heber City, Salt Lake City, and CDL employers throughout Utah.
Cutoff levels are the concentrations at which a specimen is reported positive. DOT testing uses two stages: an initial immunoassay screening cutoff and a lower confirmation cutoff measured by GC/MS or LC/MS-MS. A specimen must meet both to be reported positive.
For marijuana metabolite, the initial screening cutoff is 50 ng/mL and the confirmation cutoff is 15 ng/mL. A specimen must reach the screening cutoff first, then confirm at or above the confirmation cutoff.
The first stage is a fast immunoassay screen that flags likely positives. The second stage uses GC/MS or LC/MS-MS confirmation, which identifies the specific substance and concentration with the accuracy needed to hold up in legal and regulatory proceedings.
The cutoff levels are deliberately set to avoid positives from incidental passive exposure. Reaching both the screening and confirmation cutoffs from secondhand smoke alone is highly unlikely.
A confirmed breath alcohol concentration of 0.04 or higher is a DOT violation. A result between 0.02 and 0.039 requires removal from duty for at least 24 hours but is not a reportable violation.
No. A confirmed lab positive still goes to a Medical Review Officer, who can report it as negative if the donor provides a legitimate medical explanation, such as a valid prescription.
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