DDT (Dichlorodiphenyltrichloroethane)

DDT is the insecticide that defined modern environmentalism: Rachel Carson's 1962 book Silent Spring documented its devastating effects on birds and wildlife through bioaccumulation, helping spur the creation of the U.S. EPA and leading to a 1972 U.S. ban on its agricultural use. DDT is extremely persistent — it is still detectable in people's bodies, homes, and wildlife more than 50 years after Silent Spring was published. The 2001 Stockholm Convention on Persistent Organic Pollutants banned most uses of DDT worldwide, but carved out an exemption that remains controversial: DDT is still manufactured and sprayed by the thousands of tons each year in some countries for indoor malaria-vector control, a practice public health authorities defend as a net life-saving tradeoff even as environmental groups warn of its lingering ecological toll.