What methods are used to test for mold exposure?

Testing for Mold Exposure

Environmental testing for specific molds is usually not necessary, and there are no validated laboratory tests to assess human exposure to mold or mycotoxins in clinical practice. 1

Key Principle: Visual Inspection Over Laboratory Testing

The American Academy of Pediatrics explicitly states that testing the environment for specific molds is usually not necessary when visible mold growth is present (discolored patches, cottony or speckled growth on walls or furniture, water damage, or musty odors). 1 Visual and olfactory inspection is the most effective and practical method for identifying mold problems. 2

When Environmental Testing May Be Considered

Environmental sampling should only be performed in limited circumstances:

• When mold is suspected but not visible (e.g., persistent musty odor without obvious source) 3
• Must be conducted by qualified professionals such as industrial hygienists or indoor environmental quality consultants with expertise in evaluating indoor mold/dampness problems 3
• Air sampling requires specialized equipment and must include simultaneous outdoor air samples for comparison 3
• Interpretation criteria: Higher indoor concentrations, predominance of one mold type, or differences between indoor versus outdoor types suggest an indoor mold problem 3

Laboratory Testing for Human Exposure: Not Recommended

The American Academy of Pediatrics is unequivocal that no validated method exists to test humans for toxigenic mold exposure. 1, 4, 3

Specific Tests to Avoid:

• Mycotoxin testing in blood or urine: Not validated for clinical use and has no established correlation with health effects 4, 3, 5
• Serum antibody testing (IgG/IgA) for mold antigens: Should not be relied upon solely to confirm or rule out mold-related illness 4, 3
• Microbial volatile organic compound testing: Developed for research only, not standardized for clinical use 4, 3

These unvalidated tests propagate misinformation and inflict unnecessary costs on patients. 6

Clinical Approach for Suspected Mold-Related Illness

For Allergic/Atopic Patients:

• Skin prick testing or mold-specific IgE may be appropriate for diagnosing mold allergies 4
• Conventional allergy diagnosis methods are the standard approach 5

For Immunocompromised Patients:

When invasive fungal infection is suspected, appropriate testing includes:

• Radiological imaging (chest CT preferred over plain radiography) 4
• Microbiological cultures 4
• Serum galactomannan antigen testing for Aspergillus 4
• Immunological evaluation of immune function 4

For Suspected Hypersensitivity Pneumonitis:

• High-resolution CT looking for centrilobular ground-glass nodules, mosaic attenuation, air-trapping 4
• Clinical findings must be integrated with imaging; imaging alone cannot make the diagnosis 4, 3
• Antigen-specific inhalation challenge and lymphocyte proliferation testing are not recommended 3

Critical Pitfalls to Avoid

• Do not order environmental mold testing as part of routine medical evaluation for patients with vague symptoms 1, 4
• Do not order urine or blood mycotoxin testing—these have no clinical validity 4, 3, 6
• Do not rely on commercial laboratories offering mold-related testing panels—these are not evidence-based 6
• Do not wait for test results before recommending remediation when visible mold or water damage is present 1

Practical Remediation Approach

For areas of visible mold less than 10 square feet, individuals can perform cleanup themselves without testing. 1 Prompt cleaning within 24 hours of water damage prevents mold growth. 1 The focus should be on identifying and eliminating moisture sources rather than identifying specific mold species. 1