Is toxic exposure to mold a significant problem in this country? Absolutely. While not the only source of mold exposure, poor indoor air quality (IAQ) is likely the most common culprit. As the housing market continues to age, the percentage of homes with dangerous levels of mold present is ever-growing, especially in warm, humid climates and/or northern areas that get excessive amounts of snowfall and associated snowmelt in the spring. As this issue continues to grab the headlines, it should be understood that the health hazards of mold exposure are not just for those with sensitivity to such things or only for folks with weakened immune systems. The truth is that mold exposure can be toxic to everyone and should be avoided at all costs.
What is Mold Exposure?
Perhaps the initial question should be, “What is mold?” Mold is officially classified as a fungus and is one of the most common life-forms on earth. Nobody knows how many different species of mold exist, but the number is in the hundreds of thousands. Many species are harmless, and quite a few provide many benefits, including playing a key role by breaking down dead vegetation and making its nutrients available to the food chain. However, some species of mold are toxic to humans and other creatures and can expose them to disease-causing substances, some of which are carcinogenic. Mold can be ingested through the consumption of food and water sources, through contact with the skin, or through breathing in the spores. Spores are minute components of mold that allow for the fungus to spread and reproduce. They are so tiny that approximately 250,000 spores would fit on the head of a pin. Most mold exposure takes place indoors, but certain individuals that spend a lot of time outdoors, such as farmers or other agricultural workers, can be at risk of mold exposure as well.
Which Types of Mold are Most Dangerous?
The most well-known form of toxic mold is commonly referred to as “black mold.” This villain, which incidentally may not always be colored black, is of the species Stachybotrys. Another form of toxic mold is called Chaetomium, which is sometimes nicknamed “cast-iron mold” because of its reputation for being difficult to remove and eliminate. Both of these species can produce mycotoxins, which are substances that can be particularly hazardous to the immune system and often act as carcinogens. The list of possible symptoms from toxic mold exposure is long and frightening, as discussed below. Suffice it to say that you do not want to expose yourself or your family to these molds. They are most often found indoors in areas where water damage has occurred in the past or is presently occurring.
“Mold spores will cause some trouble, but mycotoxins are like a bullet with molds as the gun. Mycotoxins are much worse.”
Dr. Andrew Campbell
Cellulose-rich building materials such as drywall, wallpaper, insulation, or ceiling tiles are common sources of black mold and other types of mold that may be found in the same areas. The microscopic spores often spread quickly throughout the building via the heating and air conditioning systems. A home infested with these spores can be a very unhealthy environment (thus the title of a condition called “Sick Building Syndrome”). There are means to remedy the situation if it has not become too widespread. Still, sometimes the only solution, much to the dismay of the real estate industry, is to completely tear down the property and properly dispose of the materials as the toxic waste that it is.
Black mold does not smell musty, but it is often found alongside other forms of mold that may have an odor. If you find any mold in a property you work in, live in, or are considering inhabiting, I would highly suggest you take a sample and have it tested to identify it. A simple way to do this is to use a piece of cellophane tape to pick up as much of the mold as possible. Put the sample inside a plastic baggie with the mold (sticky) side against the plastic. You can then submit it to a reputable lab that specializes in home testing of mold. If you choose to, you also have the option of hiring a professional to come into your home or business and do the testing.
TIP: It is a good idea to use one vendor to determine the presence of mold in your home and identify the type, and another to do the actual mold removal if needed. This can prevent a costly and unnecessary conflict of interest.
Other types of mold that can cause disease and illness include:
- Aspergillus spp: Exposure can result in skin rashes and hair loss. Beware of low-quality vitamin and mineral supplements or other “health” products that use aspergillus fermenting in the manufacturing process.
- Aspergillus fumigates: Typically found in environments with temperatures up to 130C, such as self-heating compost sites.
- Aspergillus niger: Known to affect lung function and cause hearing loss and tinnitus.
- Aspergillus flavus: Most often, exposure occurs through the consumption of contaminated food. Can produce the highly carcinogenic mycotoxin called aflatoxin.
- Cladosporium spp: Found both inside and out, this variety is often associated with respiratory symptoms such as asthma, sinusitis, and in extreme cases, bronchospasms and pulmonary emphysema.
- Fusarium spp: Some species within this genus can produce mycotoxins that result in severe gastrointestinal disorders. A mycotoxin called zearalenone mimics the structure of the hormone estrogen and can cause illnesses of the reproductive system in women.
- Penicillium spp: Mycotoxins associated with this type of mold can affect the kidneys, liver, and nervous system. AIDS patients and other immunocompromised individuals are at greater risk for systemic infections from penicillium that can dangerously spread to organs such as the liver, spleen, and lymph nodes.
What Symptoms Are Associated with Mold Exposure?
When mold spores are inhaled or get on the skin, scientifically, you have what is called “mold exposure.” Mucous membranes in the nose, mouth, and ears are especially responsive to mold exposure. Those who reside in homes with mold and damp conditions tend to experience health concerns from direct mold exposure that, over time, can lead to dangerous health concerns. At that point, it is usually labeled as toxic mold. Less severe symptoms of mold exposure are often labeled as “mold allergies” and include the following:
- Nasal congestion
- Chronic cough
- Red, itchy, watery eyes
- Runny nose
- Chronic respiratory infections (such as the common cold)
- Skin rashes
- Sinus headaches
- Shortness of breath
- Brain fog
What are the Health Hazards of Mold Exposure?
Exposure to more toxic forms of mold, especially over an extended period of time, can lead to many types of much more serious symptoms and illnesses. A diagnosis of mycotoxicosis (“poisoning from exposure to fungal toxins”) is justified if a person has recently had at least eight of the following symptoms or conditions:
- Difficulty swallowing
- Vomiting mucous
- Autism Spectrum Disorder
- Candida Albicans
- Burning sensation in the throat and/or lungs (often mistaken for acid reflux)
- Abdominal pain
- Irritable Bowel Syndrome
- Painful or unusually dark urination
- Kidney, bladder, spleen, or liver pain
- Leaky Gut Syndrome
- Cognitive problems such as memory loss, slurred speech, confusion, brain fog, or dementia
- Vision difficulties
- Yellowing of the nails or brittle nails
- Balance difficulties
- Large boils on the neck
- Drooling while sleeping
- Night sweats
- Hair loss
- Joint stiffness and pain
- Ticks or muscle twitches
- Changes in weight
- Heart palpitations
- Heart attack
- Nose bleeds
- Reproductive system dysfunction (infertility, miscarriage, and abnormal menstrual cycles)
- Chronic Fatigue
- Extreme blood pressure, triglyceride, and cholesterol fluctuations
- Bruising or scarring easily
- Thyroid dysfunction
- In extreme cases, death.
As you can see from the above health hazards of mold exposure, mold exposure is no small matter. It can lead to serious and sometimes fatal health issues, especially when the exposure is over an extended period of time.
How Can I Prevent Mold?
There are some efficient ways that one can reduce the health hazards of mold exposure. Remember that mold can grow on just about anything that holds moisture. Keeping your home dry and controlling humidity is the key to a mold-free home. Below are some suggestions.
- Seal bathtubs and sinks with caulking to prevent water from leaking and pooling.
- Re-grout tiles to help deprive any remaining mold of oxygen and prevent growth.
- Remove excess water left on shower doors and walls with a bathroom squeegee, available at home improvement stores.
- Check window sills, walls, the roof, and the foundation regularly for condensation, moisture, or leaks.
- If you find any leaks or experience a flood, dry the area within 48 hours to prevent mold growth. Use fans to speed drying.
- Ensure good air circulation throughout the home. Open windows to air out your home when possible.
- Keep the humidity in your home at no more than 40-50%. The use of a dehumidifier or air conditioning is helpful.
- Keep your home well-ventilated.
- Always keep dehumidifiers, air conditioners, and their filters clean, as these areas can often be spots where mold may accumulate.
- Promptly tend to any water leaks in your home. This will greatly minimize the growth of mold.
- Pay close attention to certain areas of your home where mold may more easily form and proliferate. Some of these include:
- Moist areas such as kitchens, bathrooms, and basements. Use ventilation fans and exhaust fans.
- Dark areas such as closets or attics.
- Under-the-sink cabinets.
- Refrigerator door gaskets and drainage pans. Keep an eye on left-over foods, fresh fruits, and rest vegetables as they tend to grow mold quickly.
- Carpeting, especially if it has been exposed to water.
- Foam pillows.
- Washing machines.
- Dryer vents.
- If you find mold present in your home, be very careful about who you hire to eradicate it. A recent study found that 78% of mold removal contractors do an inadequate job, either due to fraud or just plain ignorance and incompetence. Make sure the company/contractor is bonded.
- Be very careful if you buy a home or are having one built. Make sure the construction is done properly using quality materials. Use a home inspector that is experienced at checking for the presence of mold.
- If your home is infested with mold, you may need to move and sell or have the home destroyed. This may be a hardship financially, but avoiding the health consequences resulting from mold exposure is priceless.
- If you work outside a lot, especially in an agricultural environment, use proper protective gear such as a respirator to avoid mold exposure. A condition known as “Farmer’s Lung” is caused by the inhalation of mold spores while handling hay, grains, feed, and other agricultural products.
Never underestimate the health hazards of mold exposure. Even the ancient Hebrews were aware of it. There are multiple passages in the Old Testament of the Bible that discuss how to handle mold and mildew. Extreme cases called for the destruction of an infected building, with the materials to be burned or hauled out into uninhabited places. This is not a modern concern, but as of late, we have become more aware of the possible health hazards of mold exposure.
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