What is the truth about toxic mold? Can it be hazardous to our health? Why all the fear-mongering?
5 Myths About Toxic Mold
Myth #1: Mold is everywhere.
While it’s true that mold is an essential part of nature, it is not true that mold exists everywhere indoors. If this were true, why would mold remediators exist? Why fix it if mold is not a big deal? Simply look at the black stain on a ceiling and it instinctively draws a feeling of unrest.
Natural molds found outdoors are not necessarily the same as molds found indoors. Stachybotrys, for example, is a greenish-black mold that grows on high-cellulose materials such as fiberboard, gypsum board, and paper. Growth occurs when there is water damage, excessive humidity, water leaks, or flooding. Stachybotrys can be found outdoors, especially in hay piles, but is certainly not found “everywhere.”
Myth #2: Mold isn’t a problem in dry climates.
Problems can occur in homes in both humid and dry climates. Mold needs only food, water, temperature, and time to grow. Given the food we provide via drywall and the water via indoor plumbing, we have the potential for toxic molds to grow in any climate.
What’s more, dry climates often rely on air conditioning for months at a time. Toxic mold can easily grow in cooling equipment and air ducts if not managed properly. Flat roofs, common in some states with arid climates, are more prone to leaks and water intrusion than slanted roofs.
Myth #3: Mold can’t hurt you.
Just like certain types of mushrooms are poisonous, the same is true for species of mold. When considering the potential for harm, it’s important to consider the role of mycotoxins. According to a study reported by the National Institutes of Health:
Mycotoxins are secondary metabolites produced by microfungi that are capable of causing disease and death in humans and other animals. Because of their pharmacological activity, some mycotoxins or mycotoxin derivatives have found use as antibiotics, growth promotants, and other kinds of drugs; still others have been implicated as chemical warfare agents.
While the emphasis in scientific literature tends to focus on mycotoxin exposure due to food contamination, mycotoxins in the indoor environment can wreak havoc on the immune system. Mold exposure is more than an allergic response; it is a form of poisoning. Consider this list of more than 300 studies compiled by the late Dr. Jack Thrasher and Dr. Irene Grant linking exposure to toxigenic contaminants found in water-damaged buildings with adverse health outcomes.
Myth #4: Just throw bleach on it.
Chlorine bleach’s ion structure prevents the chlorine from penetrating porous materials such as drywall and wood. Mold’s enzyme roots grow inside the porous materials, rendering the bleach ineffective. The water component of bleach, however, does penetrate the drywall or wood, which fosters further mold growth.
Thus, contrary to popular belief, bleach can actually make a mold situation worse. But because chlorine bleach tends to discolor or whiten the surface being treated, the building occupant may be led to believe the problem is solved—until the mold reappears.
Myth #5: Fix it yourself or call an expert.
Either of these scenarios has the potential to do harm. Small mold growth in an isolated area may be a doable project for an experienced DIYer, but the hazardous nature of toxigenic mold requires caution. Proper containment is essential when addressing a mold problem, as well as proper removal of the contaminated items.
When our family discovered mold in May 2007, we called the least expensive “experts” we could find. The company blew fans on the exposed walls, further contaminating the home and resulting in critical illness in the family. (Read our story here.) You are the expert when it comes to your health. When interviewing a prospective remediator, remember that they stand to gain from your business, so you may or may not get an objective perspective. (For more on hiring a remediator, see How to Choose a Mold Remediation Company.)
For more, see A Beginner’s Guide to Toxic Mold or listen to the podcast Is Your House Making You Sick? Toxic Mold Basics:
Listen to “Is Your House Making You Sick? Toxic Mold Basics” on Spreaker.
- 60I am the wife of Chris and mom to 9 children. I like to think outside the box and encourage others to do the same. I have an incessant curiosity about environmental health, one of the many outcomes of our family's encounter with toxic mold. (Read more here.) I am certified…
- 58One of the outcomes of a toxic mold exposure is vigilance when selecting a home or traveling. One family all too familiar with the hazards of water damage used their recent travel experience to educate State Park officials by submitting the following letter. Dear State Parks Office: We have enjoyed…
Angela Burch says
This is a great article, Andrea. Spot on.
Thanks for sharing!
Hello! Thanks for this article and all your work on behalf of us moldy people! =] Question: what did you do with your CO house and all your belongings? I’m wondering because both my husband I are sick, our house is full of mold, both visible and detectable by odor throughout the house.
I also have developed chemical sensitievities — air freshener is everywhere! Church makes me woozy =/ Did you know that grocery stores spray air freshener all over. My bags of organic carrots made our fridge smell like air freshener. Grrrrr. Feeling overwhelmed, but I have you book, you blog and MomsAware. Just haven’t seen, yet, how you handled your abandoned house and stuff? Thinking we may need to do the same. Heartbroken over it.
Found your answer! I’m listening to your episode, “Toxic Mold and Selling Your Home”, on your show, Connecting Point. Just listened to your interview with Dr. Thrasher, discussing mold and mycotoxins.
I cannot find this resource. Are you able to post a link to the Toxic Mold and Selling your Home?
Andrea Fabry says
Yes, here it is, Sandy. :
sara allison says
Thank you it makes so much sense. We were shut in the house for a week due to heavy rain and on the Sunday I woke up feeling so sick I wanted to vomit. I decide to go for a walk outside with the kids and within half an hour I felt fine. I have now found black mould and water stains in the house after closer inspection.
Eve Adams says
I just had my third Mycometrics mold test on our 8 year old home that we built. We had previously done an ERMI in 2013 which came back fine, and then in 2017 we had did a HERSTMI recommended by a dr. and it came back with high levels and a total score of 34-36. Not good. We had one company come in and supposedly remediate a small area of mold coming out of a basement drain and I small particle cleaned with wearing a respirator. We Removed basement carpet and we waited 2 months and just retested with the ERMI. Aspergillus Penicilliodis came back at 2500. Versicolor at 180, Chaetomium Globosam at 35, Europium amstelodami at 130.
Basically a total of 17.20 for Group 1
Group 2 was 12.68 so a total of 4.52.
From my understanding this is not good. There is no visible mold. Two companies that came out could’t find anything but from the drain.
What are you thoughts?
How can I find a company that knows what they are doing so this can be resolved.
I do have chronic Lyme and CIRS.
I am getting so frustrated with this and would appreciate any help you can offer.
Andrea Fabry says
Those are alarmingly high levels post remediation. I would listen to your instincts on this. If there are health issues this certainly would be contributing. Feel free to email me directly firstname.lastname@example.org
Karen Stewart says
Hello Andrea – Love your website. Thank you for so generously sharing your knowledge. Wondering if you could offer some insight on an ERMI we just got back on a home we have made an offer on. It was done using swiffer dust method performed by certified mold inspector who sent it to EMSL. HERTSMI-2 is a 4 but the ERMI is 8.4. No stachy, no chaetonium detected. All the group 1 numbers are low (below 100) except for Penicillium corylophilum which is 781. House is super dusty and we know the owner’s front load washer has lots of mold. Other than the washer, neither our mold inspector nor the house inspector could find any mold. Only even remotely suspicious spot was a bathroom with slightly higher moisture reading but nothing high enough to indicate anything probematic. Any ideas about what usually produces that kind of mold? The HERTSMI-2 mold that produced the score of 4 was Aspergillus Versicolor at 74. Any ideas you have would be great. Also, how do you feel about EMSL? Our inspector feels like their problems from 2015 have been corrected. Thank you!
Andrea Fabry says
Hmm. I’m not sure on this. The only other thought is to do thermal imaging to see if there is some type of hidden moisture. The washing machine is key to remove which no doubt you will. Go with your gut on this one.
Jeanne Phin says
I was exposed to stachybotris aspergillus penicillium on the job as,a Federal Ranger at Back Bay National Wildlife Refuge by a an air conditioner unit installed I correctly the condensation was draining inside the very small confined building. I had a heart attack soon after, seizure symptoms brain fog exhaustion hair loss metallic taste in.my mouth I can no longer work due to diminished health workman comp left it up to me to get a doctor to treat my issues and so far I have had zero success the navy clinic misdiagnosed a kidney infection I had a tumor and had to have right kidney removed.
Andrea Fabry says
So sorry to hear this, Jeanne – but I appreciate you sharing your story.
Kim Hodge says
I Had to leave my job of 15 years due to a Stachybotrys mold infestation. I worked for a gastroenterologist and he had a building built 13 yrs ago in November by a sketchy builder who was from their mosque community, it was built with synthetic stucco and has leaked for years, i have asked that they get mold testing but the dr. and his wife refused. the problem got seriously worse after hurricane harvey hit last August, although we didnt flood there was enough water to seep between the foundation and stucco and all through the ceiling. Myself and two other coworkers were extremely ill for months and one ended up in the hospital twice, even after I took tape samples of the very visible mold to a lab that does only environmental testing NOT remediation and proved that they had Stachybotrys, Cladosporium, Aspergillus and Penicillium mold throughout the entire building they refuse to have the building remediated. one coworker has been diagnosed with Lupus but perfectly healthy before starting this job a yr prior and another with Raynauds Disease again perfectly healthy prior to working in that office, unfortunately they are still there but because I had constant flue like symptoms among a whole host of other issues I left for my own safety. This is a huge problem and Sick building syndrome is a serious issue
Andrea Fabry says
I’m very grateful you took the time to share this, Kim. Good job making this connection. I know that many of us who have experienced mold exposure winced after Hurricane Harvey because we knew what was to come for many. Again, thanks for taking the time to share.
Mrs Anderson says
Thank you!! Great information! I’m buying a home and we discovered a huge mold problem and we were uncertain about to do until now.
Took an Ermi of our rental home: 8.2 with a Hertsmi of 18. Took a Hertsmi of my parents home a few weeks ago. Pre-revolutionary war house, the house I grew up in, the house my Dad still lives in. HERTSMI score of 34. This has connected so many health questions. I’m so grateful for these tests for direction as well as for those of you who share your stories to affirm that this is real and has damaged our health. In a week we leave our neighbors house to live in our new tent (family of 8) while we search for a safe home to rent.