10 Warning Signs of Mold Toxicity: Unveiling the Stealth Biohazard in Your Home

Certain types of mold can hide in plain sight. While your home might appear fresh and clean, mold can quietly spread inside drywall, underneath carpeting, and within HVAC systems. 

We'll cover the health risks posed by mold toxins, how to know when your health symptoms might be caused by exposure to mold, and how to clean it all up safely. 

What are the most common signs of mold exposure?

Mold is a normal part of the natural world. For many people, a little exposure to mold out in a park or the woods causes nothing more than a stuffy nose. For others, though, mold can cause chronic health issues, including:

• Watery and itchy eyes 

• Excessive sneezing

• Headaches

• Rashes

• Fatigue

• Sore throat

• Chronic cough

• Congestion 

• Blurred vision 

• Memory issues

These symptoms are similar to those caused by viruses and allergies, so people often overlook mold as a potential source of their discomfort. A closer look at the health problems associated with contact with mold can show how to identify possible trouble spots around your home. 

READ NOW: The Hidden Dangers of Toxic Chemicals 

Respiratory symptoms: Cough, congestion, and wheezing

Mold spores are airborne. Many molds are completely harmless. Others, like black mold (Stachybotrys chartarum) or Penicillium  can cause serious health problems.

Breathing in the spores and microbial volatile organic compounds (mVOCs) of some molds can cause respiratory symptoms in people who have mold allergies or weakened immune systems. 

Source: Photo by Edward Jenner via Pexels 

Allergic reactions: Sneezing, runny nose, and rashes

Allergic reactions occur when the immune system overreacts to a threat - environmental, food, or drug-related allergies are all common. Some of the following symptoms could be a sign of a mold allergy:

• Chronic sinus infections

• Skin rashes 

• Wheezing

• Headaches

• Chronic cough

• Nasal congestion 

As with all allergies, if you observe symptoms of anaphylaxis, call 911 or go to the emergency room right away. 

People who are allergic to mold need to be especially careful to keep mold out of the home. 

Neurological effects: Headaches, migraines, and brain fog

It's well-documented that mold causes negative physical effects. Some researchers have even suggested that mold can influence mental and neurological health, including:

• Memory problems 

• Difficulty concentrating

• Brain fog

• Depression 

• Anxiety 

In most cases, other causes sparked these issues, but there was a correlation between prolonged exposure to mold and the severity of the symptoms. 

If you feel tired or weak for no apparent reason, then it might be worth checking your home for mold. 

How does mold toxicity affect your long-term health?

Mold and dampness are widespread problems across the country. One study of 831 homes in 75 different locations across the United States revealed that 24% of homes had moisture or mold problems. 

Clearly, this is a common problem. If you don't take steps to eliminate mold quickly, it can lead to long term problems. 

Source: Andrea Piacquadio via Pexels 

Chronic respiratory issues and asthma development

Recent studies of infants in water-damaged homes showed a higher incidence of developing asthma by the age of 7. Homes with water damage are more likely to grow mold.

Mold exposure may permanently affect your lung function, especially if you already have asthma or allergies, or a suppressed immune system.  

Immune system suppression and increased susceptibility to illness

Some types of mold (like the infamous black mold) produce toxic compounds called mycotoxins. The Cleveland Clinic warns that long term exposure can lead to severe health conditions including pregnancy complications, lung scarring, immune and nervous system damage, kidney disease, and even cancer. 

Potential neurological damage and cognitive decline

Some research indicates that mold may be linked to neurological damage. Some recent studies in mice showed neurological damage and heightened anxiety when exposed to high levels of mold. 

It's notoriously difficult to definitively "prove" a particular cause for mental and cognitive conditions. As research continues, more examples of mycotoxins are shown to be present in the samples of patients who are struggling with multiple conditions, like Chronic Fatigue Syndrome. 

Even if mold isn't the primary cause of some of these conditions, it seems to be making symptoms worse. 

Where are the most common places to find toxic mold in your home?

Mold thrives in damp environments. We've all had the occasional patch of something suspicious grow in a shower that hasn't been scrubbed in a while. Depending on the type of fungus, some molds can simply be cleaned with a commercial cleaner and there are no lingering effects.

Toxic mold, however, can pose serious danger if not completely eradicated. 

Source:  Olena Shmahalo on Unsplash

Basement and bathroom: High humidity hotspots

The main culprits for mold growth in the home are basements and bathrooms. Basements frequently leak or flood, and it's very difficult to completely dry them out. This leaves a prime environment for mold to spread. 

Bathrooms are hot and humid after a refreshing shower. Without proper ventilation, that moisture sinks into the drywall, wallpaper, and fabric. This leads to a familiar musty odor that can indicate a much more extensive mold problem.

Hidden dangers: Behind walls and under carpets

It's easy to think that our homes are clean once we've wiped everything down, vacuumed, and mopped. But modern homes are made of many layers of porous material - prime growing spots for toxic mold.

These materials include:

• Wood

• Paper

• Fabric

• Drywall

• Plaster

• Cork

These materials likely make up the walls of your home, and mold can hide within the layers. It's a good idea to test regularly to make sure that mold isn't inside the walls. 

Carpets can also hide walls. If there has been a burst pipe or a water leak, the carpet should be ripped up and replaced to keep mold from growing underneath it in a warm, damp environment. 

If the wet carpet is left alone, the mold can spread into the underlayment, then subfloor, and ultimately floor joists. This can destroy the structural integrity of your home very quickly. 

Unexpected areas: Attics and air conditioning systems

Most of us don't think about our attics unless we suddenly can't find a box from the last move. Unfortunately, many attics are not properly vented.

 Sometimes, home builders or remodelers will vent the exhaust fan from bathrooms and kitchens directly into an open attic space. This directs all that warm, moist air directly into your attic, where it can quickly grow mold. Make sure that your vents are all vented outside. 

Similarly, air conditioning units can inadvertently create a home for mold if they aren't cleaned regularly. Dirty coils and filters can quickly trap spores and build up moisture. If your AC unit is growing a mold colony, then the very device that is supposed to be cleaning your air can actually spread mold spores around your homes. 

Source: Fleur on Unsplash

What are the subtle warning signs of mold toxicity you might be missing?

One of the reasons that household mold can lead to various health conditions is because it's hard to spot. If you have allergies and/or asthma, then a mold allergy will likely interact with your other symptoms and it can be hard to tell what trigger is causing which symptom!  

Adding to the confusion, "toxic mold syndrome" and "mold toxicity" are terms commonly thrown around, but they don't have a standardized medical definition yet. This can make it extremely difficult to receive a diagnosis or medical treatment for symptoms. 

Unexplained fatigue and weakness

There are a wide variety of reasons why someone might experience ongoing tiredness, aches of the muscles and joints, and a general feeling of not being well. 

Many integrative medical practitioners have pointed to chronic mold exposure as a contributor to ongoing conditions that lead to malaise, like ME/CFS or Fibromyalgia. 

Mood changes and irritability

Similar to the tiredness symptoms mentioned above, some practitioners believe that mold can affect mood. Like the other symptoms mentioned above, this is likely triggered if you have an actual mold allergy.

Persistent sinus issues and nasal irritation

People with environmental allergies have extremely sensitive immune symptoms. Breathing in substances like dust, pet danger, or mold can irritate the respiratory tract in these sensitive individuals. It's important to keep these triggers to a minimum in the home. Symptoms can include frequent sinus infections as the nasal passages are repeatedly irritated by the trigger substance. 

How can you differentiate between mold allergies and mold toxicity?

Mold allergies likely affect between 3-10% of the American population. Furthermore, people who already have other environmental allergies - dust, pet dander, pollen, etc. - are probably more likely to also have a mold allergy. 

If you suspect you might be allergic to mold, an allergist or immunologist can perform testing to be sure and determine the level of severity of your allergy. Mold-related allergies are generally manageable if you remove the causes of mold in your home. 

Mold toxicity, on the other hand, is a potentially life-threatening condition. Thankfully, it is also quite rare. Mycotoxicosis - mold poisoning - generally only happens if you actually ingest the mold, which is less common now that there are rigorous food quality laws in place. The Food and Drug Administration monitors the food supply for mycotoxins. 

Source:  Pixabay

Timing and duration of symptoms

Mold allergy symptoms vary widely. If you've spent any time in a musty basement or old building, you may have noticed a slight headache or some nasal congestion. These symptoms often go away once you're back in the fresh air or a well-ventilated building.

In some cases, mold allergies can cause severe respiratory problems, especially in people with weakened immune symptoms or asthma. In these cases, you should go to the ER or call 911 right away. 

Mold poisoning on the other hand, can lead to liver failure or death. It usually comes from ingesting a large amount of contaminated food.  Needless to say, this requires immediate emergency care. 

When should you seek professional help for mold remediation?

Many cases of household mold can be cleaned by a layperson. There are some situations, however, where you need to call in a professional to be sure. 

Since mold can thrive with even a small amount of moisture, you need to completely eradicate the current colony and the source of damp to make sure it doesn't return. 

Visible mold growth covering large areas

A good rule of thumb is that if the mold in your home or workplace covers an area larger than a bath towel (roughly 8 or 10 feet), you need to call a professional in. This generally indicates a large colony that you'll need heavy-duty equipment to remediate. 

Persistent symptoms despite DIY cleaning efforts

Sometimes, homeowners clean the area themselves but continue to experience health complications indicating mold exposure. This can be a sign that you only cleaned out the superficial level of mold, and you need a professional to cut out drywall or clean inside the attic or HVAC system. 

After water damage or flooding incidents

Flooding, burst pipes, roof leaks, and other extensive water damage is a key sign that you will probably need a professional restoration service to come and take a look. 

These events can damage the structural integrity of your home if they're left alone. Generally, it's recommended to have professional  mold remediation services in the structure in a matter of days, not weeks, to make sure that the water doesn't rot your home's structures and mold doesn't spread throughout the building. 

What steps can you take to prevent mold growth and reduce exposure?

Some regions are more prone to household mold than others - and you might be surprised by which ones.

Hot humid states like Florida and Alabama are prone to mold, but so are northeastern states like New York and New Jersey. This is likely due to the number of poorly-maintained rental properties in highly developed areas. 

Source: World Population Review  

Controlling indoor humidity levels

One of the best things you can do to prevent exposure to mold toxins is to keep the humidity levels low.

A few easy ways to do this include:

• Run the air conditioner routinely in the summer to lower humidity 

• Use an air purifier

• Use exhaust fans in bathrooms and kitchens

• Run a dehumidifier 

• Check for plumbing leaks 

• Open windows when the outside humidity is low

Generally, you'll be able to feel if your home feels humid, but some smart thermostats can also provide a readout of relative indoor and outdoor humidity. 

Improving ventilation in moisture-prone areas

As discussed above, it's imperative that bathrooms, kitchens, and clothes dryers are vented outdoors. Mold spores are everywhere, but they create problems when we create a warm, damp environment. 

Make sure that your vents aren't just releasing moisture into an attic, basement, or crawl space. This will almost certainly lead to mold. 

Regular inspections and prompt addressing of water leaks

It's a good idea to have your HVAC systems inspected annually to make sure there are no compressor leaks. These can accumulate moisture and dirt, which is a prime environment for mold growth. 

Additionally, if you notice that there are issues with your water pressure, that might be a signal that you need to replace or repair your plumbing equipment. Water leaks can be slow and quiet, and often happen inside walls or under cabinets. Unaddressed, they can lead to much bigger problems, like needing to rip out flooring or entire shower and tub units to eliminate mold. 

Source:  Sidney Pitzl on Unsplash

Conclusion: Know the Effects of Mold and how to Protect your Home

Chronic exposure to mold can lead to long term health effects and destroy the value of your home. Be prepared by knowing the signs and symptoms of mold exposure, dealing with leaks and water damage quickly, and seeking professional cleanup services when needed.