The Dangers of Mold: Is Your House Making You Sick?

by | Updated: March 31st, 2017 | Read time: 4 minutes

Where there is moisture, there is mold. That makes mold pretty common.

Mold can be a menace to your health and home. But you can keep it in check by following a few key suggestions.

Person's Hand Wearing Glove Cleaning Wall with Mold |

Sometimes the fuzzy stuff won’t mess with your health, according to the Centers for Disease Control and Prevention. But it can. Things get bad when there’s lots of mold or you’re particularly sensitive to it.

According to the national Institute of Medicine, scientific studies offer evidence linking indoor mold with problems of the upper respiratory tract, such as coughing, in otherwise healthy people. And if you have asthma, indoor mold will bring out your symptoms.

To help you understand mold and how to keep it in check at home, we’ve rounded up answers to key questions, with help from the CDC, U.S. Environmental Protection Agency and World Health Organization.

Where does mold come from?

Mold is natural. Mold spores—which are far too small to see—float through the air and attach to clothing, pet hair and all sorts of other things. They also can get into your home through open doors or windows. Mold often starts growing indoors when spores land on wet surfaces.

How do I know if my home has mold?

Mold comes in a range of colors: black, white and pink, to name a few. If you see mold, that’s usually enough to tell you it’s there, according to the EPA. There are no federal limits for mold or mold spores.

Sometimes, though, mold doesn’t show itself. For example, it could be on the back of wallpaper or dry wall. It could be under ceiling tiles or carpets, inside ductwork or in roof materials above ceiling tiles. Walls near pipes that have not been insulated are another possibility.

If any part of your home flooded and didn’t dry out properly, mold could be lurking. Leaky windows, roofs and doors invite mold too. Mold will grow on cardboard, paper and wood, according to the CDC. It can also grow in paints, insulation, fabric, upholstery – even dust.

If a building or room smells moldy but you don’t see any evidence, investigate, the EPA suggests. It might be a good idea to have professionals do that. Why? If you pull back wallpaper, for example, you can release spores if mold has taken hold behind the paper.

Is mold bad for me?

Mold certainly has the potential to cause health problems if you inhale or touch it. It produces irritants and allergens. In some cases, it also produces potentially toxic substances called mycotoxins.

How will my body react if I’m exposed to mold?

Even if you’re not allergic to it, mold can irritate the eyes, skin, nose, throat and lungs. Your nose might feel stuffy and your throat might feel irritated, for example.

What if I’m allergic?

Allergic reactions to mold are common, according to the EPA. Mold can cause sneezing, a runny nose, red eyes and a skin rash. It can cause asthma attacks in people with asthma. Also, folks with compromised immune systems or chronic lung illnesses could get serious lung infections, the CDC warns.

The EPA notes that research on mold and health effects is ongoing, so what we’ve talked about here isn’t the final word.

How do I get rid of mold?

If the moldy area is less than about 10 square feet, you probably can handle the job yourself, following guidelines from the EPA. Remove mold from hard surfaces with soap and water or a solution of up to one cup of household laundry bleach and one gallon of water. If you’ve got mold stains, try a natural treatment such as Clean Earth Mold Stain & Mildew Stain remover.

It’s critical to clean up mold and fix the moisture problem. Otherwise the mold will come back.

Absorbent or porous materials, such as ceiling tiles and carpet, probably have to be thrown away. That’s because mold can fill in the empty spaces and crevices of porous materials, making it impossible to remove completely.

According to the EPA, while you clean moldy areas you might want to wear an N-95 respirator, gloves that extend to the middle of the forearm and goggles (without ventilation holes).

The EPA suggests considering cleaning air ducts if there is “substantial mold growth” inside hard-surface ducts or on other components of the heating and cooling system. But the agency also warns of many caveats

You don’t need to worry about what kind of mold is in your home in order to remove it (there are thousands of strains). In fact, the CDC doesn’t recommend sampling or do routine sampling itself.

How can I to prevent mold?

  • Keep humidity levels at 30 percent to 50 percent and no higher than 60 percent.
  • Fix leaks in your home’s roof, walls or plumbing.
  • Dry out your home thoroughly and quickly—24 to 48 hours—after flooding or a spill.
  • Consider not using carpet in areas like bathrooms or basements, which tend to have moisture.
  • Make sure the ground slopes away from your home’s foundation, so that water doesn’t enter or collect around the foundation.
  • Clean and repair roof gutters regularly.
  • To prevent condensation, cover cold water pipes with insulation. A rusty pipe is an indicator of condensation build-up. Condensation on pipes, windows or walls can be a sign of high humidity.

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