Well, the infrastructure to distribute diluted chemicals into the water supply by sector already exists.
I'm sure there's something else besides fluoride that could help save humanity through aqueducts...
That thought led me to this :
Antiandrogenic interventions (hormonal or metabolic) will block testosterone (possibly irreversibly, see finasteride). This will affect sperm production, but will also result in androgen deficiency.
Cytotoxic chemicals used in chemotherapy (e.g. cisplatin) affect sperm production, which involves many germ cell divisions. But this is also likely to damage the Leydig cells.
Papaya extract action on sperm motility is reversible.
https://chemistry.stackexchange.com/questions/37014/chemicals-that-can-sterilize-males
Papaya extract study :
[–] Master_Foo 0 points 2 points 2 points (+2|-0) ago
We need a solution that specifically targets the irresponsible population and does not affect the responsible population.
Putting stuff in the water supply is an indiscriminate solution.
Abortion, however, is 100% effective in targeting irresponsible people. Only irresponsible people get abortions.
[–] Rotteuxx ago
Nah, it's manageable by sector through pump houses. Doing anything at the filtration plant is just crazy talk.