Mold Exposure Testing: What Medical and Home Tests Can and Cannot Tell You

This guide is general information, not medical advice. Decisions about medical testing belong with your doctor.

"Mold exposure testing" covers two different questions. One is about your home: is there mold, where is it, and how much? The other is about your health: is mold affecting you? Different tests answer each one, and some widely marketed tests answer neither. Knowing which is which can save money and worry.

Two questions, two kinds of testing

Most people need both a doctor's view of the symptoms and a fix for any moisture and mold in the house.

Medical tests doctors use

Allergy testing. Skin prick tests and blood tests for IgE antibodies show whether your immune system is sensitized to specific molds. They help diagnose mold allergy and guide treatment. They do not show how much mold is in your home.

Tests for specific conditions. Depending on symptoms, a doctor may evaluate asthma, hypersensitivity pneumonitis, or, in people with weakened immune systems, fungal infections. The tests involved depend on the condition and are chosen by the doctor.

The American College of Medical Toxicology (ACMT) notes that fungal antibody tests, including IgE and IgG, can be clinically useful in assessing immune conditions such as common allergies and hypersensitivity pneumonitis, but that they give no information about the source or amount of exposure to mycotoxins.

Urine mycotoxin tests: why medical groups advise against them

Some clinics and online labs sell urine tests for mycotoxins, the chemicals some molds can produce, and present results as proof of "mold toxicity." Medical and public health organizations have raised several concerns:

• Not validated. ACMT's 2025 position statement says this method has not been validated in well-designed studies and is not recommended for assessing human exposure to mycotoxins.
• Not FDA approved, no reference ranges. A Navy and Marine Corps Public Health Center fact sheet notes there is no FDA-approved test for mycotoxins in urine, no validated levels that predict disease, and no reference ranges for healthy people.
• Not recommended by the CDC for people in water-damaged buildings. The same fact sheet notes that the CDC does not recommend biologic testing of people who work or live in water-damaged buildings.
• Food is a common source. Mycotoxins can come from foods and drinks such as grains, fruit, coffee, and wine, so a result does not show that your home is the source.
• Real harm from false positives. A 2015 CDC report described a worker whose unvalidated urine test was read as "positive," leading to a mold toxicity diagnosis, an antifungal prescription, and nonstandard treatments. Destructive testing of her office, costing more than $25,000, found no water damage or significant mold.

ACMT also states that allergic conditions, not toxic effects from inhaled mycotoxins, are the primary health concern with indoor mold, and that there is no toxicological evidence, diagnostic test, or treatment supporting inhaled mycotoxins from indoor mold as a cause of systemic toxicity.

If a provider recommends a mycotoxin test, reasonable questions to ask are: Is the test FDA approved? What reference range is it compared against? How will the result change my treatment?

Testing your home

For the house, the EPA's advice is that in most cases, if mold growth is visible, sampling is unnecessary, and no federal limits exist for mold or mold spores. Testing helps when growth may be hidden, when you need documentation, or to confirm cleanup worked.

Be cautious with dust DNA tests sold under the name ERMI. The EPA developed ERMI as a research tool, says it has not been validated for non-research purposes, and does not recommend its routine public use in homes.

Our guide on how to test for mold covers home testing options, and what a mold inspection involves explains the process.

A practical order of steps

1. If you have symptoms, see a doctor. Describe the symptoms, the home, any mold or water damage, and when things started.
2. Check the home for moisture and mold. Look for leaks, stains, musty smells, and visible growth. See signs of mold in your house.
3. Fix the moisture and remove the mold. Small areas on hard surfaces can often be cleaned; larger or hidden growth needs a professional.
4. Protect people at higher risk. Keep anyone with asthma, allergies, chronic lung disease, or a weakened immune system away from moldy areas and cleanup.

For what symptoms health agencies associate with mold, see black mold symptoms.

Next step for the house

If you own your home and suspect mold, especially hidden mold, a local inspector can find the moisture source and the extent of the problem. You can call the number on this page to be connected with an independent mold inspection or mold testing company.