Starting in the late 1950s, prior to the book's publication, Carson had focused her attention on environmental conservation, especially environmental problems that she believed were caused by synthetic pesticides. The result of her research was "Silent Spring", which brought environmental concerns to the American public. The book was met with fierce opposition by chemical companies, but, owing to public opinion, it brought about numerous changes. It spurred a reversal in the United States' national pesticide policy, led to a nationwide ban on DDT for agricultural uses, and helped to inspire an environmental movement that led to the creation of the U.S. Environmental Protection Agency.