For effect, The Population Bomb is #2 to Silent Spring.
Another work of fiction that has killed untold number of people world wide.
#3 is
Coming of Age in Samoa: A Psychological study of Primitive Youth for Western Culture by Margaret Mead (New York: Morrow, 1928), which portrayed Samoans as leading happy and satisfied lives because due to permissive lifestyles and lack of moral restraints--which is the opposite of how they actually lived. According to the Intercollegiate Studies Institute, Margaret Mead's sloppily researched book "misled a generation into believing that the fantasies of sexual progressives were an historical reality on an island far, far away."
In 1961, I am ashamed to say, my mother had to introduce Margaret Mead at a presentation.