Can Mold Make You Sick?

There’s no "safe" level of mold exposure — if you see it, remove it

Mold is one word that can send any homeowner into a panic. It can wreak havoc on walls, ceilings and wood, leaving nasty stains and musty odors in its tracks. But what really is this dreaded intruder, and could it be to blame for those unexpected respiratory illnesses?

“Molds are naturally occurring fungal growths found indoors and out,” says Jonathan Spahr, MD, director of pediatric pulmonology at Geisinger. “They can be anywhere moisture and oxygen are present, but tend to seek out warmer climates or decaying matter to feed on to accelerate growth. This makes our homes a great target.”

Mold growth speeds up when it’s indoors. Mold’s tiny reproductive cells, called spores, are easily released into the air, and an enclosed space amplifies their ability to make contact with one another.

There are hundreds of species of mold. Some are less dangerous, like penicillin, which has antibacterial properties and is used in antibiotic medication. But other species could be harmful and make you sick.

“Though small amounts of mold probably won’t hurt us, there is no species of mold that is ‘safe’ when inhaled,” says Dr. Spahr. “Those tiny spores could cause a host of health problems, mostly in people with respiratory problems, allergies or a compromised immune system.”

Mold exposure symptoms

Mold spores can irritate your nose, throat and lungs when inhaled or aggravate your skin if you touch them. Symptoms can range from mild to persistent and often resemble seasonal allergies or a cold, which can make mold-related illness easy to miss.

“If you suspect mold may be to blame, pay attention to where symptoms arise,” says Dr. Spahr. “If you feel worse at home, at work or in a specific room, but then symptoms improve when you leave that environment, mold could be a contributing factor.”

Common mold exposure symptoms can include:
Sneezing, nasal congestion or runny nose
Itchy, watery or red eyes
Scratchy throat, postnasal drip or cough
Skin rash or hives
Headache and fatigue

“People with asthma are more likely to have worsening symptoms like wheezing, chest tightness or asthma flare-ups,” says Dr. Spahr. “And those with a chronic lung disease like COPD, mold allergies or weakened immune systems are at higher risk for more serious respiratory symptoms or infections.”

Thankfully, once mold is removed, symptoms most likely will go away.

When to call the doctor about mold exposure

Contact your provider if you have persistent or worsening symptoms, asthma that’s harder to control or signs of infection like fever and chills.

If you suspect mold exposure and have an underlying chronic respiratory condition or impaired immune system, talk to your doctor. They can monitor symptoms and adjust treatment, if necessary.

How to get rid of mold

If you see — or smell — mold, you should remove it before it gets worse. Mold spores can lay dormant for years after they are produced and could begin growing at any time, leaving allergens active for long periods. Because of this, regular cleaning with agents that kill mold or professional mold remediation is always ideal.

Mold remediation begins by identifying the source of the moisture and making any necessary repairs, then removing all the porous material in a room to be replaced with sanitized material. All hard surfaces need to be thoroughly cleaned with an anti-fungal detergent and completely dried before porous materials like drywall or carpeting can be reinstalled.

“Be sure to protect yourself from exposure by wearing gloves, goggles and a mask, if possible,” says Dr. Spahr. “Also, open windows and run exhaust fans to ventilate the area and direct air outdoors.”

If mold covers a large area, or has gotten into the drywall, ceilings or floors, it’s best to bring in a professional.

How to prevent mold in your home

Prevention centers around controlling moisture, improving ventilation and keeping at-risk areas like bathrooms, basements, kitchens and attics clean.

Here are a few ways you can prevent the spread of mold in your home:

Keep an eye out for hidden leaks: Wet spots on your ceiling, baseboards or floor are a telltale sign of a leaky pipe or roof. Your home’s pipes are behind drywall, which can leave a small leak unnoticed for a long time.

Mold can grow behind those walls and filter into the air through ducts or pipes. A plumber or contractor can help identify weak spots or possible leaks and prevent mold growth.

Keep your air conditioner clean: Many air conditioners, especially window units, are susceptible to mold growth. They often trap moisture, creating a breeding ground for spores. Choosing a unit with humidity control can prevent moisture buildup. Leaving the device running at a low or “automatic” level during the day will keep air circulating and prevent a serious rise in humidity. You should also replace filters every 3 months, or as recommended.

“Your home should always maintain less than 60 percent humidity in order to stop mold production,” says Dr. Spahr. “And keeping ducts free of dirt and dust also eliminates the organic matter on which mold can feed.”

Ventilate heat-prone rooms: Bathrooms, kitchens and laundry rooms create a lot of excess heat and humidity, whether it be from the shower, stove or dryer. All of these rooms should be well ventilated with exhaust fans — preferably to the outdoors — to prevent the lingering moisture that attracts mold. It’s also important to keep these areas clean using mold-killing household products.

It’s not necessary or even recommended to test your home for mold.

“The health effects of mold are different for everyone, and there is no ‘safe’ level of mold exposure,” says Dr. Spahr. “The fact remains: No matter what type of mold is present in your home, you need to safely remove it and prevent future growth to protect you and your family’s health.”