Why is Mold Growing in My House?

Molds are part of the natural environment.  Outdoors, molds play a part in nature by breaking down dead organic matter, such as fallen leaves and dead trees.  But indoors, mold growth should be avoided.  Molds reproduce by means of tiny spores; the spores are invisible to the naked eye and float through outdoor and indoor air.  Mold may begin growing indoors when mold spores land on surfaces that are wet.  There are many types of mold, and none of them will grow without water or moisture.

Can mold cause health problems?

Molds are usually not a problem indoors, unless mold spores land on a wet or damp spot and begin growing.  Molds have the potential to cause health problems.  Molds produce allergens (substances that can cause allergic reactions), irritants and, in some cases, potentially toxic substances (mycotoxins).

Inhaling or touching mold or mold spores may cause allergic reactions in sensitive individuals.  Allergic responses include hay fever-type symptoms, such as sneezing, runny nose, red eyes, and skin rash (dermatitis).  Allergic reactions to mold are common.  They can be immediate or delayed.  Molds can also cause asthma attacks in people with asthma who are allergic to mold.

In addition, mold exposure can irritate the eyes, skin, nose, throat and lungs of both mold-allergic and non-allergic people.  Symptoms other than the allergic and irritant types are not commonly reported as a result of inhaling mold.  Research on mold and health effects is ongoing.  This article provides a brief overview; it does not describe all potential health effects related to mold exposure.

For more detailed information, consult a health professional.  You may also wish to consult your state or local health department.

Taking air samples during a mold inspection is important for several reasons.  Mold spores are not visible to the naked eye, and the types of mold present can often be determined through laboratory analysis of the air samples.

Having samples analyzed can also help provide evidence of the scope and severity of a mold problem, as well as aid in assessing human exposure to mold spores.  After remediation, new samples are typically taken to help ensure that all mold has been successfully removed.