Our health, and the health of wildlife, depends on a clean environment. Since the advent of the industrial revolution, our environment has suffered from waves of pollution as different technologies came to the fore, each with its own set of practical benefits and associated chemical waste. Perhaps the most insidious of these environmental pollutants is lead. With us to discuss the history of lead as an environmental contaminant is Bruce Lanphear. For over 30 years, Bruce has investigated how toxic chemicals harm human health, especially the health of children. His research helped shape U.S. federal standards for lead in air, water, and house dust, and played a key role in the landmark conclusion that no amount of lead is safe for children.