Mold Spore

A mold spore is a tiny reproductive cell that mold releases into the air so it can spread and grow in a new spot. Spores are present in nearly all indoor and outdoor air in small numbers, and they become a problem when they land on a wet or damp surface and begin to grow into visible mold. Breathing in or touching mold spores can trigger allergic reactions, irritation of the eyes, skin, nose, throat, and lungs, and can worsen asthma in people who have it.