What lab tests are used to diagnose black mold exposure?

Diagnostic Testing for Black Mold Exposure

There are no validated laboratory testing methods that exist for diagnosing toxigenic mold exposure, including black mold (Stachybotrys chartarum). 1

Environmental Assessment Rather Than Blood Tests

Environmental sampling, rather than laboratory testing of patients, is the appropriate approach for confirming black mold exposure:

• Environmental sampling should be performed by qualified professionals such as industrial hygienists or indoor environmental quality consultants 2, 1
• Air sampling requires specialized equipment and expertise 2
• When air sampling is conducted, outdoor samples should be collected simultaneously for comparison 2
• Higher indoor concentrations, predominance of one mold type, or different types indoors versus outdoors suggest an indoor mold problem 2

Why Laboratory Tests Are Not Validated

Several factors explain why laboratory tests for black mold exposure are problematic:

• Assays to detect mycotoxins and microbial volatile organic compounds in blood have been developed but are not standardized for clinical use 2
• It is unclear what levels of these compounds are associated with health effects 2
• Immunoassays for mold have not been standardized for clinical use 2
• 90% of field-collected Stachybotrys spores are not culturable, making detection difficult 3
• Not all strains of Stachybotrys produce detectable trichothecene toxins, so presence of the mold does not confirm toxin exposure 3

Clinical Approach to Suspected Mold Exposure

When mold exposure is suspected, the following approach is recommended:

1. Evaluate for allergic responses:

   • Skin-prick testing or in vitro tests for specific IgE antibodies may help identify allergic mechanisms 1
   • Note that these tests have limitations for fungal allergens 1

2. Assess symptoms and physical findings:

   • Common symptoms include rhinitis (62%), cough (52%), headache (34%), respiratory symptoms (34%), CNS symptoms (25%), and fatigue (23%) 4
   • Physical examination may reveal pale nasal mucosa, pharyngeal "cobblestoning," and rhinorrhea 4

3. Environmental investigation:

   • Environmental sampling may be useful when there is suspicion of mold (e.g., musty odor) but no visible growth 2
   • Look for signs of mold growth including discolored patches, cottony growth, water stains, condensation, and musty odors 1

Important Considerations and Pitfalls

• The concept of "toxic mold syndrome" is controversial, with many reported symptoms being attributed to allergic rather than toxic responses 4, 5
• There is no compelling evidence that exposures in most mold-contaminated indoor environments result in measurable health effects beyond allergic responses 3
• Health-based exposure standards for molds and mycotoxins do not exist 3
• The CDC and American Academy of Pediatrics consider Stachybotrys chartarum a serious health threat, but quantitative standards relating to health effects are lacking 2, 3

Management Recommendations

The most effective approach to addressing potential black mold exposure is:

1. Environmental remediation:

   • Remove all contaminated material 3
   • Clean accessible HVAC parts and filters 3
   • Implement preventive maintenance 3
   • For areas <10 ft², individuals can clean using appropriate methods 1
   • For larger areas, professional remediation following EPA guidelines is recommended 1

2. Symptom management:

   • Treat allergic symptoms with antihistamines and/or nasal corticosteroids 1
   • For asthma/bronchial hyperresponsiveness, consider inhaled β-agonists and corticosteroids 1
   • Maintain indoor humidity below 50% using dehumidifiers 2, 1

Remember that the primary approach to addressing black mold concerns is environmental assessment and remediation rather than laboratory testing of patients, as there are no validated clinical tests for black mold exposure.