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850 Health Hazards in Construction
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Fungi (Mold) Hazards

Fungi (mold) are found everywhere–both indoors and outdoors, all year round. The terms fungi and mold are often used interchangeably, but mold is actually a type of fungi. About 72,000 species have been identified, and more are being discovered every day. Most, if not all, of the mold found indoors comes from outdoor sources.

mold on wall and floor of room
Mold tends to grow in damp or high humidity areas.

How Molds Affect the Body

Molds produce and release millions of spores small enough to be airborne. They can also produce toxicagents known as mycotoxins. Spores and mycotoxins can have negative effects on human health. The most common route of entry into the body is through inhalation; mold has a characteristic smell–if you smell mold, you could be inhaling mold. Mold is generally visible; however, some of the most toxic mold spores are small enough to be considered respirable [less than 10 micrometers (10 μm) in diameter].

Knowledge Check Choose the best answer for the question.

3-3. Most, if not all, of the mold found indoors _______.