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Molds can cause allergies year-round. (3 min. read)

Among the many allergens floating around your world, mold spores may be lower on your list of concerns than pollen, dust mites and animal dander.

Yet they can be every bit as bothersome as their better-known sneeze-causing counterparts. And like other allergens, mold spores can often be avoided.

What is mold?

Hundreds of types of molds exist, and they all have at least one thing in common—they are fungi. These organisms reproduce by sending their tiny seeds, or spores, into the air.

To survive, the spores need food, air, the right temperature and water, according to the American Academy of Allergy, Asthma & Immunology (AAAAI).

Mold is common in buildings and homes and will grow anywhere indoors where there is moisture, according to the AAAAI. In particular, molds like damp, warm environments and can grow on practically any surface.

What makes mold dangerous?

Mold spores, like pollen, can trigger potentially dangerous allergic reactions in people who are sensitive to them. Molds can also trigger attacks in people who have asthma. But they don't affect only those with allergies or asthma. Molds can also irritate the eyes, skin, nose, throat and lungs in nonallergic people.

Allergic reactions occur when the body detects an unwelcome guest, such as mold spores, and tries too hard to get rid of the invader. During this attack, the body's immune system overreacts and releases potent chemicals, such as histamine, that can cause sneezing, a stuffy or runny nose, watery eyes and itching.

More severe allergic reactions to molds can also occur. These can be life-threatening. For some people, exposure to molds can even cause anaphylaxis. Anaphylaxis is a potentially fatal allergic reaction that must be treated immediately. Symptoms differ from other allergic reactions because they begin more quickly, are more severe and involve the whole body.

Where is mold found?

Molds can be found year-round indoors in places such as attics, basements, bathrooms, refrigerators and other food storage areas, garbage containers, carpets and upholstery.

Outdoors, molds are found in soil, vegetation and rotting wood. The outdoor spores show up after a spring thaw and reach their peak in July in warmer states and October in colder climates, according to the AAAAI.

Outdoor molds can be found year-round in the South and on the West Coast.

What can you do?

The National Institutes of Health and the Centers for Disease Control and Prevention offer the following tips for reducing your exposure to mold:

• Use a dehumidifier or air conditioner to keep relative humidity in your home below 50%. The machines also keep the air cooler.
• Vent your bathrooms and clothes dryers to the outside.
• Check for leaks in your home's faucets, pipes and ductwork.
• When first turning on the air conditioner in your home or car, leave the room or drive with the windows open for several minutes to disperse mold spores.
• Get rid of decaying debris, such as leaves, twigs and grass clippings, from your yard, roof and gutters.
• If you have to do yardwork, wear a mask and avoid working on hot, humid days.
• Avoid raking leaves, mowing lawns or working with peat, mulch, hay or dead wood.

Reviewed 6/27/2024