Some 85,000 chemicals are used in modern commerce today. Surprisingly few have been tested for their potential to affect children's health. Of these many compounds, pesticides are among those explicitly designed to harm living things. While significant efforts have been made to design pesticides and pesticide application practices to avoid human harm, the lessons of modern toxicology are that we rarely fully understand all the risks. Surprises are inevitable. The foundation has thus funded work to deepen scientific and public understanding of pesticide risks and to expand efforts to protect children's health from environmental harm.