By Rachel Dodgen
What is the first thing that pops into your head when you hear the word “mold”? Is it the fuzzy blue stuff showing up on your forgotten leftovers? Or is it the black spots creeping under your sink? Maybe it’s the musty smell coming from your grandparent’s old shed? Perhaps several news stories pop into your mind with warnings of “toxic mold”? Whatever it is, it likely isn’t a pleasant thought or image. And when you actually see mold in person, especially indoors, it causes panic. Or if you’re a weirdo building science nerd like me, it causes intrigue.
Mold is an essential member of the natural world and human history. Mold breaks down organic material which leads to unwanted food spoilage, but that same process also gives us delicious cheeses and beer. Mold also has its hand in the creation of penicillin (literally named for the mold Penicillium from which it is derived), antibiotics, and other pharmaceuticals. It’s even responsible for some of the amazing colors seen in the thermal areas of Yellowstone. Unfortunately for mold’s reputation, it is also responsible for home destruction and illness – though not as much as you might believe.
Mold is everywhere. You cannot avoid it. There are microscopic mold spores on your body right now. They are being filtered out by the hairs and mucus that line your nose and throat at this very instant. It is on every surface of your home just waiting for the right condition to grow just as they do outside. And our homes are not far from the perfect environment for mold to take over! Nearly everything we build and fill our homes with is made from their favorite food (any organic material like wood and cotton, even dust!) and countless species prefer the same temperature as us (most comfortable between 50°F and 80°F). The limiting factor for mold growth in our homes is water. Mold likes a lot of it, and we prefer our buildings on the drier side.
Unwanted mold growth in your home is a clear indication of one thing – a moisture problem. Honestly the mold is kind of doing you a favor. It’s like, “Hey, you! See I’m growing over here? That’s because it’s real wet and I’m gonna start eating up your house. Hope that’s cool. I may cause it to rot away and thousands of dollars in damage if you ignore me, but otherwise I can lead you to the problem!” And you’ll respond, “Thanks mold! I’ll get right to that leaky pipe or that cold spot causing condensation or that high humidity.” And then you live happily ever after. Except the mold, he dies off when the water issue is solved, but don’t worry because there’s billions of spores just like him, ready to warn you about the next problem. There are likely some growing just out of sight somewhere else in your home, and that’s okay. It is unrealistic to expect a 100% mold free building. A healthy home just doesn’t have mold actively growing or an excessive amount – excessive as in you are very aware of its presence, either through site or smell.
Now let’s touch base on that whole “toxic mold” concern. Toxic mold (most commonly black mold) is not as big of an issue as we (the average homeowner) often perceive, and some black spots in your home is not an indication you will get sick. The science around mold and mold causing disease is honestly thin. Exposure to mold can lead to sickness or allergic reactions, but exposure is more involved than just seeing it. Exposure means inhaling, ingesting, or absorbing a piece of mold, mold spore, or mycotoxin (a chemical some molds produce for defense), and there’s no definitive answer for how frequently, how readily, or how dangerously that occurs. Even if you are truly exposed, you won’t necessarily have a reaction. Sensitivity to mold varies widely from person to person, with the most at risk being those with asthma and the immunocompromised. We generally understand that “a lot of mold” can be bad and sensitivity can worsen overtime. That’s about as definitive as the science gets.
So yes, mold is bad. But mold is also not that bad. It is simply taking advantage of the cozy environments we build and then it’s trapped in this environment where our potential for exposure continually increases as the mold remains. Bottom line is, if you can see mold and/or smell mold, you need to identify your water problem and fix it. Otherwise, you can thank mold for modern medicine and especially stinky cheese and look forward to the future of mold-inspired discoveries