They can invade your home, making you sick and forcing you out. They can stalk you on vacation, turning a dream trip into a nightmare.
They are the silent killers medical and environmental problems that strike without warning, causing serious and even fatal - illnesses.
48 Hours looks at four of these killers through the eyes of some of their victims.
Toxic Mold - Since the movie bearing her name appeared, everyone knows who Erin Brockovich is: the working mother who traced illnesses in a small California town to groundwater contaminated by Pacific Gas and Electric.
Fatal Flights - Brad Perkins loves the water. It's a love the 43-year-old California lawyer always shared with his son Danny, his daughter Clarice, and his wife, Karen.
Danger in the Attic - In the small town of Libby, Montana, where the air is clean and the streams are clear, something strange is going on.
Death Boats - For Ken and Bambi Lynn Dixey and their four boys, summer vacation has always meant houseboating on Lake Powell in southern Utah. Ken, a dentist living outside of Denver, co-owned a share of a 55-foot Stardust Cruiser, a common craft on Lake Powell and other large lakes around the country.
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