“The present vast overpopulation, now far beyond the world carrying capacity, cannot be answered by future reductions in the birth rate due to contraception, sterilization and abortion, but must be met in the present by the reduction of numbers presently existing. This must be done by whatever means necessary.” — Initiative for the United Nations ECO-92 EARTH CHARTER

“Childbearing [should be] a punishable crime against society, unless the parents hold a government license … All potential parents [should be] required to use contraceptive chemicals, the government issuing antidotes to citizens chosen for childbearing.” -David Brower, first Executive Director of the Sierra Club

I remember reading an article about the Sierra Club in which the proposal to add a chemical "birth control" to municipal water supplies (the same way fluoride is added) and other sources was raised.  The problem, apparently, goes to what Mr. Brower said above in that there isn't currently an antidote that can be administered to counteract such "birth control" chemicals that are being ingested because the antidote is, obviously, to stop taking the first chemicals which would not be conveniently done when they are being added to the water supply to begin with.