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Mold Exposure: Symptoms, Treatments and Testing Options with Dr Melanie Maciver

Updated: Feb 26, 2022

We are all somewhat familiar with mold: most of us have encountered at least one kind of visible mold, maybe in a basement or bathroom affected by water damage, or on food that’s gone bad in the fridge.

There are over 150,000 different kinds

of mold out there, and although all mold grows and thrives in moist conditions, not all mold is easy to detect (or to avoid). There are many different kinds of indoor mold that can lead to toxicity and harm by producing toxic byproducts called mycotoxins that can cause widespread inflammation and a multitude of symptoms. Mold toxicity can go unrecognized for long periods of time, but is often the missing puzzle piece underlying treatment-resistant or persistent chronic illness.

What Are Mycotoxins?

Mycotoxins are toxic substances produced by mold that can cause systemic harm when we are exposed to them. Although our immune systems are generally able to fight and clear these toxins at least to some extent, mycotoxins can easily build up in the body and cause a wide variety of symptoms in vulnerable individuals.

It is estimated that approximately 25% of the population is susceptible to mold toxicity from mycotoxins. This susceptibility is due to either a genetic predisposition, a weakened immune system (often because of a chronic infection or accumulation of other toxins), or a combination of both.

The real danger in mycotoxin-induced illness is in its insidious nature. Unlike an allergic reaction that occurs upon exposure and tends to cause “classic” allergy symptoms such as difficulty breathing or skin rashes, mold toxicity tends to take hold gradually and can affect pretty well any system in the body, from the nervous system to the immune system to the gastrointestinal tract, by triggering inflammation– making it hard to know where your symptoms are coming from, and what’s causing them.

Mold, Mycotoxins & Inflammation

When we are exposed to mycotoxins, our bodies initiate an immune reaction intended to fight off foreign intruders. Unfortunately, in many cases, our body’s defence is not enough to fight mycotoxins (often because of an already weakened immune system). Instead, these toxins build up in our systems, causing persistent, low-grade, widespread inflammation.

Inflammation, whether caused by mycotoxins or not, is at the root of an overwhelming number of chronic diseases. And as with other environmental-toxin-induced illnesses, mold toxicity is difficult to pinpoint because of its ability to manifest in so many different ways and in different parts of the body, all through inflammation. This systemic inflammation often ends up being misdiagnosed as anything from Chronic Fatigue Syndrome or fibromyalgia to depression to IBS depending on the nature of the symptoms. Many people end up living with these misdiagnoses for months or years, unable to find a treatment that works for them, as they haven’t yet determined the root cause of the inflammation underlying their symptoms.

Symptoms of Mold Toxicity

Symptoms of mold toxicity vary and may include any combination of the following. Note that you may also be experiencing symptoms not listed below. Inflammation caused by mycotoxins can present itself in many different ways, and this list is not exhaustive.

  • Fatigue; Chronic Fatigue Syndrome

  • Joint pain

  • Allergies; asthma; difficulty breathing

  • Sinus infections; sinusitis

  • Digestive issues; leaky gut; stomach pain

  • Headaches

  • Depression; anxiety

  • Difficulty focusing; memory issues

  • Brain fog

  • Weakness; aches

  • Chronic infections

  • Skin issues; sensitive skin

  • Coughing; shortness of breath

  • Histamine intolerance

Mold Exposure toxicity frequently goes undetected or misdiagnosed, as its symptoms often overlap with symptoms of other chronic conditions including Lyme disease, Chronic Fatigue Syndrome or fibromyalgia, leaky gut, and IBS. If you have been trying to recover from one of these conditions and can’t seem to get better, it is worth looking into the possibility that mold toxicity may be underlying your symptoms.

It is fairly common for mold toxicity to occur alongside persistent infections or chronic Lyme, putting a further strain on the immune system and making it more difficult to heal.

Sometimes, mold toxicity comes first, and begins a cascading effect by lessening our ability to ward off other infections and illnesses. Other times, mold toxicity occurs when the immune system is already weakened because of other infections, or illnesses. In some cases, mold may have been present in the home or workplace for some time without affecting us, and we may only begin to experience symptoms when our body becomes overloaded with other toxins or infections and no longer has the capacity to battle the mycotoxins.

Mold toxicity is especially problematic for those who are already suffering from a chronic infection or illness such as Lyme disease or Chronic Fatigue Syndrome. It is therefore very important to identify and address as early on as possible.

How to Identify, Remove, and Prevent Mold at Home

If you suspect that mold toxicity may be behind your symptoms, the first step is determining where the mold is coming from, and removing it (or, if possible, getting away from the area altogether).

Mold grows and thrives in moisture, so the first thing to look for is any obvious water damage in your home or office. Of course, in coastal British Columbia and the Pacific Northwest, moisture is inevitable, making us particularly prone to mold exposure. Basements that have flooded during heavy rainfall are common culprits, as well as leaking pipes and windows. In addition to moisture, mold enjoys darkness, warmth, and certain construction materials including drywall and wood. Basements, bathrooms, and laundry rooms are the most likely places. You’ll want to look for current leaks as well as signs of past water damage, such as discoloured surfaces.

There are a number of mold testing options for homes, which may be worth investing in if you’re having trouble finding an obvious source. Some companies will come out to your house for an inspection, while others will send you a kit that can be used to collect samples from different areas for testing.

Once you’ve identified the source of indoor mold, steps need to be taken to clean and remove it. It’s important not to use bleach, which may clean a moldy surface but will actually feed the mold hidden beneath it.

Of course, if you’ve discovered a leak of any kind, it will need to be fixed right away. Materials close to water damage such as carpets and tiles should be removed and thrown away as they may be holding onto mold. To ensure that water damaged areas are cleaned properly and that mold has been thoroughly eliminated, you may want to seek the help of a local mold specialist.

A HEPA air filter may be a worthwhile investment to help rid the air of mold and its byproducts (and other toxins). A propolis vaporizer will also help to kill mold and mycotoxins.

There are a number of precautions that can be taken to prevent future growth of mold– especially important when you live in an area prone to flooding. You may not spend much time in your basement, and we don’t always notice minor leaks right away, but being on the lookout can help to eliminate mold-feeding moisture problems before they have the chance to cause too much damage.

Using the fan while cooking and cleaning is helpful, as well as leaving the fan on during and after showers. Small fans can also be used throughout the house once a week or so to help circulate air.

Surfaces should be regularly cleaned with vinegar. If you’ve discovered an area in your home that is prone to water damage, it’s best to keep the area fairly sparse (avoid putting in carpets or other absorbent materials, just in case).

Testing For & Healing From Mold Toxicity

If you’ve identified mold in your home or office– or if you haven’t yet found the source but believe that you may be suffering from mold toxicity– the next step is to work with a practitioner who is experienced with its diagnosis and treatment, and who understands the widespread inflammatory effects of mycotoxins.

Naturopathic testing for mold toxicity is available. This is a simple urine test, and can be a helpful place to start. Treatment is focused on safely eliminating mycotoxins and detoxifying while supporting and healing the immune system and the digestive tract. Binders, substances including activated charcoal and bentonite clay that bind to mycotoxins and assist in their elimination, may be used in the initial stages of treatment. Antifungals are another critical part of a mold toxicity protocol. It is important not to try to detoxify from mold-related illness without the support of a practitioner who will help you to develop a protocol that is safe and individualized for you.

If you suspect that mold toxicity may be at the root of your symptoms or are interested in testing, book an appointment with Dr. Melanie MacIver ND here.


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