If you have allergy symptoms year-round -- or if they get worse in damp
weather -- you may be allergic to mold. While people with pollen allergies tend
to have seasonal symptoms, mold allergies can flare all year long. Indoor mold
can be a problem in winter months, because mold will grow in your house where
there is enough moisture -- whether it's on a basement wall, in your crawl
space, a damp carpet, or behind the bathroom tile.
You may not even realize the mold is there -- but if you're sensitive you'll
react with coughing, wheezing, stuffy nose, or irritated eyes.
"Very often, people don't really know what the problem is," says
John Martyny, PhD, an industrial hygienist with National Jewish Health Center
in Denver. "They have an allergic reaction, lots of sinus drainage, lots of
upper respiratory problems, and it doesn't last for just a month or two. This
goes on 12 months a year. It is not a minimal problem -- it can really change
We’re all exposed to mold spores. Mold is a fungus that breaks down plant or
animal matter, like leaves, wood, dirt, and food. It’s present both indoors and
out. The trouble comes with a mold allergy, when mold spores trigger reactions
like allergic rhinitis or asthma. Molds can also produce volatile organic
compounds (VOCs) -- the musty odor that irritates eyes, nose, and throat.
Black Mold: Toxic or Not?
What's known as black mold (Stachybotrys chartarum) is a slow-growing
mold that grows only on wood, paper, and cotton. It’s often called "toxic
black mold," but the mold itself is not poisonous.
"There's no question that the mold spores are very potent, but they are
given off in extremely low levels," he tells WebMD. "It's really just
another mold. What we see is an allergic reaction or
Black mold has been blamed for serious lung problems in a small number of
infants, but that has not yet been proven. It's not uncommon for people to
develop an allergy to mold -- not just black mold, says David Lang, MD, head of
allergy/immunology at the Cleveland Clinic. "Infants, small children, and
elderly adults are more likely to react to any type of mold," he says.
It may be hard to get a mold allergy correctly diagnosed. "Very often,
the root of the problem isn't identified correctly," Martyny says.
"People have these symptoms, but they don't realize they have a moisture
and mold problem at home. If you get rid of the allergens -- the mold -- people
get better, and they get better pretty fast."
In some cases, mold exposure can cause serious respiratory problems, with
symptoms like chest tightness and difficulty breathing. "Some people who
are exposed to high levels of any mold for a long time develop lung
hypersensitivity -- which leads to scar tissue in the lungs," Martyny
explains. "Some people recover when the mold source is removed. But if
they've been exposed for a long time, they may never recover."
Coughing, wheezing, runny nose, irritated eyes or throat -- these are all
signs of mold allergy. Mold allergies can also trigger an asthma attack, with
symptoms like wheezing, coughing, and shortness of breath. If you have these
symptoms, see an allergist for skin testing or a blood test to diagnose mold