1967 - Environmental Defense Fund
After the Publication of "Silent Spring" DDT (Dichlorophenyltrichloroethane) was primarily targeted. In 1967 Environmental Defense Fund (EDF) was formed by a group of scientists and lawyers to bring forth laws to ban the usage of DDT. EDF went to courts to stop Suffolk County Mosquito Control Commission from spraying DDT on the marshes of Long Island.
DDT is toxic to many animal forms other than insects, such as sea shrimps and many species of fish. Although it is less toxic to mammals some amphibian species were effected. The exact biological thinning mechanism of bird eggs is not entirely known. But there is evidence that DDE ( Dichlorophenyldichloroethylene) has played a major role in it. The thinning of the eggshells caused the eggs to crack before they were hatched thus reducing the number of off springs drastically. DDE results from the breakdown of DDT.
Since then EDF has brought forth many laws for the well being of the environment.