Q What is the difference between mold and mildew? Do they both stink? What's black mold and why is it so dangerous?

A There's not much of a difference; basically, mildew is a form of mold that grows in a flat, net-like pattern.

Mold spores are everywhere, indoors and outdoors. They typically aren't a problem indoors unless they land on a wet or damp spot and begin growing. As molds grow, they digest whatever they are growing on. They rot wood, damage wallboard and eventually cause structural damage to buildings. Mold can stain furnishings and affect the health of occupants.

Some molds, but not all, produce strong odors as they grow. The musty smell suggests that mold is present and needs to found and eliminated, but it doesn't necessarily mean the mold is dangerous.

Molds produce allergens (substances that can cause allergic reactions). Inhaling or touching mold or mold spores may cause allergic reactions in sensitive individuals, and repeated exposure has the potential to increase sensitivity. Allergic responses include hay fever-like symptoms such as headache, sneezing, runny nose, red eyes and skin rash (dermatitis)

Moisture is the most important factor influencing mold growth indoors. Controlling indoor moisture helps limit mold growth. You can never get rid of mold spores, however, so moisture control is the key to mold control.

Mold also needs nutrients to grow. That's supplied by any organic substance: food, paper, cloth, wood, plant material and even soil.

Molds come in many colors, including white. Sometimes the terms "toxic mold" and "black mold" are used, but black mold isn't automatically dangerous.

Under certain circumstances, some molds can produce potentially toxic byproducts called mycotoxins. More than 200 mycotoxins from common molds have been identified, and many more remain to be identified.

Some mycotoxins are known to affect people, but for many mycotoxins, little health information is available. No one can tell whether a mold is producing mycotoxins just by looking at it, and research is continuing. Exposure to mycotoxins can occur from inhalation, ingestion or skin contact. Because there's always a possibility of mycotoxin and because not everything is known about them, it's a good idea to avoid unnecessary exposure to mold. That means that when you smell or see mold, find the moisture source and eliminate it. Then clean up the mold and monitor the area so it stays dry and mold-free.

U.S. Environmental Protection Agency

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