More than 4 decades ago Rachel Carson, in "Silent Spring," first warned that man-made chemicals were taking a deadly toll on birds and wildlife. Now we are recognizing that chemicals are effecting human sexual development and reproduction and can cause central nervous system diseases, cancer, and liver disease. Everyone is carrying a dizzying array of chemical contaminants, the by-products of industry that contribute to a host of health problems in ways just now being understood. These toxic substances, unknown to previous generations, accumulate in our fat, bones, blood, and organs as a consequence of womb-to-tomb exposure. Almost everything we encounter-from soap to soup cans and computers to clothing-contributes to a chemical load unique to each of us. Scientists refer to it as "chemical body burden." Chemical companies would rather consumers never knew about the potential dangers their products pose.

Nena Baker is a former staff writer for The Arizona Republic, The Oregonian, and United Press International. Her award-winning investigation of Nike's Indonesian factories led to numerous improvements for workers. She is the author of The Body Toxic.