At first I was incredulous. Why were so many people showing up in my office with mold sickness—in Tucson, Arizona, of all places?

It turns out that, while mold grows in damp places, spores can survive in incredibly adverse conditions, including in dry deserts—and reanimate when the conditions are better. Like in your walls after a rain. Or in your vents. Or under your sink. Or in your floorboards after a leak.

What Mold Is

There are three primary categories of microorganisms involved in human illness (not counting the parasites): viruses, bacteria, and fungi. Mold is in the third category.

Most of us think of mold as the black stuff we can see, but fungi release spores into the air to reproduce. Sometimes this can give off a musty smell, but sometimes if you’re not sensitive, you won’t see or smell a thing. That’s part of what can make mold so tricky to diagnose. It can also grow almost anywhere there’s dampness and oxygen.

Types of Mold

  • Allergenic mold: These don’t usually cause problems unless you’re allergic and/or exposed to a lot of them. These include alternaria, cladosporium, and penicillum.
  • Pathogenic mold: These are molds that can produce infections if you’re immunocompromised. Aspergillus is one example, as it can cause the lung infection aspergillosis.
  • Toxic mold: These molds release mycotoxins and are harmful regardless of allergic potential. Aspergillus also releases mycotoxins so it would fit here too, as do some species of penicillum (this is where we get the antibiotic penicillin from, actually). The most toxic form of mold is stachybotrys, or “black mold.” That’s the one most of us think of. You can absorb the mycotoxin produced by stachybotrys, trichothecenes, through your gut, lungs, and skin. They’re fat-soluble, so you can also store them for a long time.

Screening for Mold

Some of my patients will get swab test kits (like from for $100) or petry dishes (from Home Depot, and I believe they run around $30). But these only work for mold you can see (which is useful, because it’s possible to mistake allergenic molds for stachybotrys, and the only way to know what you’ve got for sure is to test it). If you suspect mold but can’t see it, the best way to find out if you have a problem is via air sampling from air quality assurance companies who specialize in mold. The same company should not also offer remediation (since you won’t know whether their assessment is accurate or not), and they should offer forensic quality testing.

It’s possible to test for antibodies against some of the types of mold listed, but this will only tell you if you are allergic; it won’t tell you if you’re toxic from mold exposure. The best test for this, as I have learned from some of the mold docs in Tucson with whom I share patients, is the cytokine TGFb1. High levels indicate toxicity. I’ve also run a specialty test in some cases that measures mycotoxins directly, though that one can be pricier. But in many cases, if my patients already know they’ve been exposed, we just treat it and see if they improve. 

Mold Treatment

Mold treatment usually involves remediation and/or avoidance, binding and eliminating it (with activated charcoal, or prescription meds cholestyramine or colestipol), and treating the other fungi that tend to come with it (usually candida or other yeast). Sometimes a good detox protocol is also necessary, especially for patients who also have a lot of chemical sensitivities in addition to mold issues. Leaky gut also shows up secondary to this more often than not.

Some cases clear up pretty quickly after getting away from the mold source, and some are more complicated. But definitely the first step is finding out whether mold is part of your issue.