Basement dehumidifiers are safe and can save homeowners thousands of dollars in repair costs if they have damp basements. Dehumidifiers are the number one way of combating the humidity and condensation that can cause metal pipes to rust, wood to swell and mold to replicate.
Liquid from ground or rainwater, unvented clothes dryers, heat from the kitchen or humid air coming from the exterior of the house and into the basement causing condensation are all causes of basement dampness. Dampness can lead to the spread of mold spores, which thrive in moist atmospheric conditions. A heavy presence of mold spores will affect people with allergies and could make anyone who inhales them sick.
To have a fresh smelling and comfortable basement it's important to invest in the proper dehumidifier. Things to take into consideration before purchasing a dehumidifier are humidity levels and size of the basement. Many modern models come with features such as hygrometers to read humidity levels, auto shut off and adjustable humidistats for selecting proper moisture levels.
There is no documentation of dehumidifiers being dangerous to home owners, and in fact under the right circumstances the presence of a dehumidifier will generally make a home more comfortable and safer.