Drug Test Cutoff Levels: Urine, Oral Fluid, and Hair

Drug test cutoff levels are the minimum concentrations of a drug or its metabolite that must be present in a specimen before a laboratory reports the result as positive. The Substance Abuse and Mental Health Services Administration sets the federal cutoffs through its Mandatory Guidelines, most recently updated in January 2025 to cover both urine and oral fluid.1Federal Register. Mandatory Guidelines for Federal Workplace Drug Testing Programs-Authorized Testing Panels Anything below the cutoff is reported as negative, even if a trace amount is technically detectable. The specific numbers matter because they determine whether secondhand exposure, a prescription medication, or foods like poppy seeds can push a test into positive territory.

How the Two-Stage Testing Process Works

Every federally regulated drug test runs in two rounds. The initial screen uses immunoassay technology to flag specimens that exceed a threshold for a broad drug class. It’s a filter. It catches anything that looks like marijuana metabolites, cocaine metabolites, opioids, and so on, without pinpointing the exact molecule. A specimen below the screening cutoff stops there and is reported negative.

A specimen above the screening threshold moves to confirmatory testing, which uses gas chromatography-mass spectrometry or liquid chromatography-tandem mass spectrometry to identify the specific metabolite and measure its concentration. Confirmation cutoffs are often lower than screening cutoffs because the equipment is more precise and targets a single molecule instead of a class. If the confirmation test finds the target metabolite below its own cutoff, the result is negative despite the initial flag. The confirmation number is the one that controls.

Federal Urine Cutoff Levels

Urine is the most common specimen for federal workplace testing. Concentrations are measured in nanograms per milliliter (ng/mL). The following numbers come from the 2025 SAMHSA Mandatory Guidelines, which bind federal agencies and serve as the model most private employers adopt.1Federal Register. Mandatory Guidelines for Federal Workplace Drug Testing Programs-Authorized Testing Panels

Marijuana

The screen for the marijuana metabolite (delta-9-THC carboxylic acid, often called THCA) is 50 ng/mL. Confirmation drops to 15 ng/mL. The 50 ng/mL screening threshold was set high enough that passive smoke exposure almost never triggers a positive. A 2015 study found immunoassay screening at 50 ng/mL produced negative results in over 99 percent of specimens from non-smokers exposed to cannabis smoke in unventilated rooms.2PubMed Central. Non-Smoker Exposure to Secondhand Cannabis Smoke. I. Urine Screening and Confirmation Results

Cocaine

Cocaine testing targets the metabolite benzoylecgonine at 150 ng/mL for screening and 100 ng/mL for confirmation.

Opioids

Codeine and morphine share a screening threshold of 2,000 ng/mL. Their confirmation levels split: codeine confirms at 2,000 ng/mL, morphine at 4,000 ng/mL. Those thresholds are intentionally high to keep poppy seed consumption from producing positives.3PubMed. Experience with a urine opiate screening and confirmation cutoff of 2000 ng/mL

Heroin use is identified through the 6-acetylmorphine metabolite. Because 6-AM is a unique marker of heroin and isn’t produced by any food or legal medication, both screening and confirmation cutoffs are just 10 ng/mL.

Amphetamines and MDMA

Amphetamine and methamphetamine share a 500 ng/mL screening cutoff, with confirmation at 250 ng/mL for each substance individually. MDMA and its metabolite MDA use the same 500 ng/mL screening and 250 ng/mL confirmation levels. The amphetamine class is a common source of screening false positives; some decongestants and antidepressants cross-react on the immunoassay, and the confirmation test then clears them.

Phencyclidine

PCP carries a 25 ng/mL cutoff for both screening and confirmation, reflecting its chemical stability and the absence of common cross-reactive substances.

Federal Oral Fluid Cutoff Levels

The 2025 SAMHSA guidelines formally authorized oral fluid (saliva) as a federal testing specimen for the first time, with an effective date of July 2025. Oral fluid testing measures parent drugs rather than metabolites, which means it detects recent use, generally within the past 24 to 48 hours, rather than use from days or weeks earlier. That shorter window fits post-accident and reasonable-suspicion testing.

The oral fluid panel is broader than the urine panel and adds fentanyl as a standalone analyte. Cutoff levels are measured in ng/mL for undiluted (neat) oral fluid:

  • THC: 4 ng/mL screening, 2 ng/mL confirmation
  • Cocaine and benzoylecgonine: 15 ng/mL screening, 8 ng/mL confirmation for each
  • Codeine and morphine: 30 ng/mL screening, 15 ng/mL confirmation for each
  • Hydrocodone and hydromorphone: 30 ng/mL screening, 15 ng/mL confirmation for each
  • Oxycodone and oxymorphone: 30 ng/mL screening, 15 ng/mL confirmation for each
  • 6-Acetylmorphine: 4 ng/mL screening, 2 ng/mL confirmation
  • Phencyclidine: 10 ng/mL screening, 10 ng/mL confirmation
  • Fentanyl: 4 ng/mL screening, 1 ng/mL confirmation
  • Amphetamine and methamphetamine: 50 ng/mL screening, 25 ng/mL confirmation for each
  • MDMA and MDA: 50 ng/mL screening, 25 ng/mL confirmation for each

Oral fluid cutoffs are much lower than urine cutoffs for most drug classes because concentrations in saliva are naturally much smaller. These thresholds reflect parent drug entering saliva from the bloodstream, not accumulated metabolites filtered through the kidneys over days. Someone who might test negative on a urine screen taken two hours after use, before the metabolite has built up, could test positive on an oral fluid screen taken at the same time.

Hair Testing Is Not Yet a Federal Specimen

Hair testing offers the longest detection window of any specimen type, roughly 90 days from a standard 1.5-inch sample. SAMHSA has not finalized mandatory federal guidelines for hair. A proposed rule was published in 2020 and a revised version remains under review. Until those guidelines are final, hair results are generally not accepted for federal workplace testing programs, and hair testing operates under laboratory-validated protocols rather than a uniform federal standard.

Hair concentrations are measured in picograms per milligram (pg/mg). Industry cutoffs commonly used by testing laboratories include a marijuana metabolite screening threshold of 1 pg/mg, a cocaine screening threshold of 500 pg/mg, and opiate screening thresholds around 200 pg/mg. Confirmation levels vary by drug class and by lab. Environmental contamination is a live concern; laboratories use wash procedures before analysis, but those methods are not standardized across the industry.

Specimen Validity Thresholds

Before a laboratory analyzes a urine specimen for drugs, it checks whether the specimen is genuine human urine. Specimen validity testing runs on every federal specimen, and its results determine how the sample is handled.

Dilute

A specimen is dilute when creatinine falls between 2 and 20 mg/dL and specific gravity is greater than 1.0010 but less than 1.0030.4Substance Abuse and Mental Health Services Administration (SAMHSA). Medical Review Officer Guidance Manual for Federal Workplace Drug Testing Programs Dilute readings commonly result from drinking a lot of water before the test. Under DOT rules, if creatinine on a negative-dilute specimen is between 2 and 5 mg/dL, the employer must order an immediate recollection under direct observation.5eCFR. 49 CFR 40.67 – When and how is a directly observed collection conducted?

Substituted or Adulterated

A substituted specimen has creatinine below 2 mg/dL and specific gravity at or below 1.0010 or at or above 1.0200. Those values fall outside the range the human body produces. A specimen is flagged as adulterated if the pH is below 3 or above 11, or if nitrite reaches 500 micrograms per milliliter or higher.6Nuclear Regulatory Commission. 10 CFR Part 26.161 – Cutoff levels for validity testing Substituted and adulterated results are treated as refusals to test under federal rules, which carry the same consequences as a positive.

Why a Lab Positive Is Not the Final Word

A laboratory positive does not automatically become a reported positive. Every non-negative result first goes to a Medical Review Officer, a licensed physician trained in substance abuse testing, who reviews the result and interviews the donor before making a final determination. Legitimate explanations, prescription medications most often, can produce a lab positive that shouldn’t count against the employee.

Once the MRO receives a confirmed positive, the employer’s designated representative contacts the employee and instructs them to reach the MRO within 72 hours.7eCFR. 49 CFR 40.131 – How does the MRO or DER notify an employee of the verification process after receiving laboratory confirmed non-negative drug test results? In a confidential interview, the MRO explains the result and gives the employee a chance to provide a medical explanation, such as a valid prescription for a controlled substance. If the medication is prescribed consistent with federal controlled substance laws, the MRO can verify the result as negative.8eCFR. 49 CFR 40.135 – What does the MRO tell the employee at the beginning of the verification interview?

When a valid prescription raises a safety concern, an airline pilot on a sedating opioid, for example, the MRO allows five business days for the employee’s prescribing physician to discuss whether the medication can be changed. If the concern isn’t resolved in that window, the MRO reports the safety issue to the employer without disclosing the medication. Miss the 72-hour contact window entirely and the MRO can verify the result as positive without ever speaking to you, which forfeits the prescription defense.

DOT and Private Employer Variation

The Department of Transportation applies drug and alcohol testing to safety-sensitive workers in aviation, trucking, rail, transit, pipeline, and maritime industries through 49 CFR Part 40.9eCFR. 49 CFR Part 40 – Procedures for Transportation Workplace Drug and Alcohol Testing Programs DOT testing uses the SAMHSA cutoff levels. What differs is the consequence: a positive or a refusal removes the employee from safety-sensitive duties immediately, and a Substance Abuse Professional-directed return-to-duty process is required before the employee can go back.

Private employers who are not federally regulated have latitude in how they design their programs. Most adopt the SAMHSA cutoffs because they are a defensible national standard, but nothing prevents a private employer from setting stricter thresholds. Some safety-critical industries do exactly that; nuclear energy regulations explicitly allow licensees to establish more stringent levels than the federal baseline.10eCFR. 10 CFR 26.163 – Cutoff levels for drugs and drug metabolites Going the other way, using cutoffs higher than the federal standard, produces a program less sensitive than the recognized benchmark and can expose the employer to liability if a drug-related incident later brings the program under scrutiny. State laws also affect what private employers can require and what procedural safeguards employees receive. For most private programs, the SAMHSA cutoffs are the floor, not the ceiling.