Mosaic Diagnostics (MycoTOX) Review: Is It Worth It?

What is the Mosaic Diagnostics MycoTOX Profile?

The MycoTOX Profile is a mail-in urine test that measures mycotoxins, the toxic compounds that certain molds produce. It is sold by Mosaic Diagnostics, the lab that used to be called The Great Plains Laboratory (GPL) before it rebranded. If you have seen older forum posts or practitioner notes that mention a "Great Plains MycoTOX" or "GPL MycoTOX," that is the same test under the old name.

Here is the key thing to understand up front. This is a body test, not a building test. It looks at what shows up in your urine, which is one of the ways your body clears water soluble compounds. It does not sample your air, your dust, or your walls. So it belongs in a different category from an ERMI dust test or a professional inspection, and it answers a different question. We will come back to that distinction, because it is where most buyers get confused.

Mosaic markets the MycoTOX Profile to people who suspect mold or mycotoxin exposure, especially those who live or work in water damaged buildings, and who are working with a practitioner to look into it. The test is popular in functional and integrative medicine circles. It is far less accepted in mainstream medicine, which is a real and important part of this review, covered in the accuracy section below.

How the MycoTOX Profile works, step by step

The process is straightforward and happens mostly at home.

Step 1: Order the kit. You order through a practitioner, through Mosaic directly as a patient in some regions, or through a third party lab platform such as Rupa Health, Walk-In Lab, or DirectLabs. The kit ships to your door.

Step 2: Do not take glutathione first. This is a detail people get wrong. Some competitor tests ask you to take a "provoking" agent like glutathione before you collect, to try to mobilize toxins. Mosaic advises the opposite. It tells you not to take glutathione before its urine test, because glutathione can lower your results. Follow the exact instructions in the kit.

Step 3: Collect a first morning urine sample. You collect your first urine of the morning in the provided cup, since that sample is the most concentrated. You then freeze it as directed.

Step 4: Ship it back frozen. You pack the frozen sample with the enclosed materials and mail it to the lab.

Step 5: The lab runs mass spectrometry. Mosaic analyzes the sample using liquid chromatography tandem mass spectrometry, usually written as LC-MS/MS. This method can detect very small amounts of specific compounds, down to parts per trillion. The lab also applies a creatinine correction, which adjusts for how dilute or concentrated your urine was so that hydration does not skew the numbers.

Step 6: You get a report. Results usually come back in about 5 to 10 business days after the lab receives your sample. The report lists each mycotoxin it looked for and the level found, plotted against the lab's own ranges. Most people review it with the practitioner who ordered it.

What it tests for and what you get

The MycoTOX Profile measures 11 mycotoxins produced by roughly 40 species of mold. These are the compounds on the panel, grouped by the molds that commonly make them:

• Aflatoxin M1 (AFM1) and Sterigmatocystin (STC), associated with Aspergillus species.
• Ochratoxin A (OTA), associated with Aspergillus and Penicillium.
• Gliotoxin (GTX), associated with Aspergillus.
• Mycophenolic Acid (MPA), associated with Penicillium.
• Citrinin (CTN), measured through its metabolite dihydrocitrinone, associated with Penicillium and Aspergillus.
• Chaetoglobosin A (CHA), associated with Chaetomium, a mold often found in water damaged buildings.
• Zearalenone (ZEA) and Enniatin B1 (ENB1), associated with Fusarium.
• Roridin E (ROE) and Verrucarin A (VRA), macrocyclic trichothecenes associated with molds like Stachybotrys, the group commonly called black mold.

What you get is a lab report. For each of the 11 compounds you see the level detected, adjusted for creatinine, next to the range the lab uses to flag a result as higher than expected. You do not get treatment instructions, a diagnosis, or an inspection of your home. It is a set of numbers, and it needs a knowledgeable person to interpret it in context.

Pricing and what is included

Because Mosaic sells through practitioners and multiple lab platforms, the price you pay depends on where you order. Across the sellers we checked, the MycoTOX Profile lists in the range of roughly $275 to $330. Some platforms show a discounted price against a higher list price, so the exact number moves around. Always confirm the current price on the official site or the platform you use before you buy.

What is not included is worth stating plainly. There is no home inspection, no environmental sampling, and no clinical consultation bundled with the base test. If you want help reading the report, that is usually a separate cost with your practitioner. And a single test is a snapshot, so people who track this over time end up paying for it more than once.

Accuracy, science, and credentials

This is the section that matters most, and it has two sides.

What is genuinely strong

The analytical method is real and sensitive. LC-MS/MS is a respected laboratory technique for identifying and measuring specific molecules, and it can detect these compounds at parts per trillion. Mosaic also uses mass spectrometry rather than the ELISA antibody method some competitors use, which tends to produce fewer false positives for this kind of small molecule work. The lab itself carries recognized credentials: it is CLIA certified and CAP accredited, and various listings also cite ISO 15189 and additional state and industry certifications. Those credentials mean the lab follows quality controls for running its equipment and handling samples.

The honest limitation

Here is the part a balanced review has to say clearly. Lab accreditation is not the same as clinical validity. The U.S. Centers for Disease Control and Prevention has specifically flagged urine mycotoxin testing as unvalidated for diagnosing illness. Its key points, which apply to this whole category and not to Mosaic alone, are worth quoting:

• "There is no FDA-approved test for mycotoxins in human urine," and these tests "are not approved by FDA for accuracy or for clinical use."
• CLIA certification "does not address the clinical validity of testing," meaning it does not confirm the test predicts your actual health status.
• "Low levels of mycotoxins are found in many foods; therefore, mycotoxins are found in the urine of healthy persons," and "mycotoxin levels that predict disease have not been established."

Independent research backs this up. Studies of thousands of healthy people have found that a very large share test positive for urinary mycotoxins from ordinary dietary sources alone, and validated population reference ranges are limited for most of these biomarkers. On top of that, results do not always agree between labs, partly because panels, methods, and prep instructions differ from one company to the next.

None of this means Mosaic runs a bad lab. It means the number you get back is hard to interpret on its own. A high reading can reflect food, not a sick building. A low reading does not clear a home. That is why the test is best treated as one input, read by someone who knows its limits, rather than a verdict.

Pros and cons

Pros

• Real, sensitive method. LC-MS/MS measures specific compounds down to parts per trillion.
• Mass spectrometry, not ELISA. For this kind of testing it tends to yield fewer false positives than antibody based methods.
• Accredited lab. CLIA certified and CAP accredited, with documented quality controls.
• Simple at home collection. One first morning urine sample, no blood draw, no clinic visit.
• No provocation required. You do not take glutathione beforehand, which removes a step some other tests add.
• Creatinine correction. Adjusts for hydration so a very dilute or concentrated sample is less likely to skew the numbers.
• Broadly available. Orderable through many practitioners and lab platforms.

Cons and limitations

• Not FDA approved for diagnosing illness. The whole category of urine mycotoxin testing is unvalidated for clinical diagnosis per the CDC.
• Diet confounds the result. Mycotoxins show up in the urine of healthy people from food, so a positive is not proof of a mold problem.
• Limited reference ranges. Validated population baselines are lacking for most of these biomarkers, which makes "high" hard to define.
• It says nothing about your home. A urine test cannot locate mold or tell you which room is the source.
• Results vary between labs. Different companies can return different readings on similar samples.
• Cost and coverage. Roughly $275 to $330 and usually out of pocket, and one test is only a snapshot.
• Needs expert interpretation. The raw report is just numbers and is easy to misread without guidance.

Who it is best for, and who should skip it

Best for

• People already working with a functional or integrative practitioner who ordered the test and will interpret it in context.
• People with a known water damaged building exposure who want a body focused data point to track over time under guidance.
• People who understand it is one input, not a diagnosis, and who plan to pair it with proper environmental testing.

Who should skip it

• Anyone trying to answer "does my house have mold?" A urine test is the wrong tool for that. Test the building instead.
• Anyone expecting an FDA validated diagnostic. This is not one, and no urine mycotoxin test is.
• Anyone hoping a single number will settle a health question on its own. Levels that predict disease have not been established.
• Budget conscious buyers who have not yet found or fixed the source. Spend the first dollars locating and stopping the moisture, not on a body test.

How Mosaic MycoTOX compares to alternatives

There are two very different families of "mold tests," and mixing them up is the most common mistake. One family looks at your body. The other looks at your building. Mosaic is in the body family.

Other urine mycotoxin tests (body)

Mosaic MycoTOX vs RealTime Laboratories: RealTime uses the ELISA antibody method and tests 16 mycotoxins, and it asks you to provoke with glutathione before collecting. Mosaic uses mass spectrometry, tests 11, and tells you to avoid glutathione. Different methods and prep, so the results are not directly comparable.

Mosaic MycoTOX vs Vibrant Wellness: Vibrant also uses mass spectrometry but runs a larger panel of around 31 mycotoxins. A bigger panel is not automatically better, since more analytes without validated reference ranges can mean more numbers that are hard to interpret. It does cover more compounds if breadth is what you want.

Across all three, the same category level caveat applies: none is FDA validated for diagnosing illness, and results can differ from lab to lab.

Environmental testing (building)

If your real question is about your home, an ERMI or HERTSMI-2 dust test is the relevant tool. These use mold DNA analysis on household dust to score your home's mold burden against a national database. They tell you about the building, not your body. Many practitioners use environmental and urine testing together, but they answer separate questions, so a urine result should never stand in for testing your home.

Professional inspection and DIY identification

A licensed or ACAC certified mold inspector can find hidden moisture, sample air and surfaces, and tell you where growth is. That is the highest confidence way to assess a building, and also the most expensive. At the other end, a phone based mold identification app and a good step by step testing guide let you locate visible growth and decide what needs a closer look, for far less money. Compared to a $300 urine test, those are usually the smarter first spend, because they tell you whether there is a mold problem to investigate at all. If you want a physical kit, see our take on the best mold testing kits.

Our verdict and rating

Rating: 3.5 out of 5. The Mosaic MycoTOX Profile is a genuinely well run test. The lab is accredited, the mass spectrometry method is real and sensitive, the at home collection is simple, and Mosaic is upfront about avoiding glutathione beforehand. If you already have a practitioner guiding you and you understand what the number can and cannot mean, it can be a reasonable data point.

We hold it back from a higher score for reasons that are bigger than the lab. Urine mycotoxin testing is not FDA approved for diagnosing illness, healthy people commonly test positive from diet, validated reference ranges are limited, and results vary between labs. Most importantly for a mold website, the test tells you nothing about your home. If your goal is to figure out whether you have a mold problem and where it is, the money is better spent locating and fixing the source first, then testing the building if needed. Use MycoTOX as one input under expert guidance, not as a standalone answer to a health or housing question.