She had survived a bout with cancer. Her scientific methods were problematic. Her friends said a book on the chemical poisoning of the environment was too depressing. But the publication of "Silent Spring" by marine biologist Rachel Carson, warni ng against the unregulated use of agricultural pesticides - particularly DDT - dramatically changed public attitudes and governmental regulations about the environment. This PBS video tells her story. Written and produced by Neil Goodwin; narrated by Ale x Chadwick. Closed captioned.