Seriously impair the brain performance...

From that barium link:

In 1970, former National Security advisor Zbigniew Brzezinski wrote in  Between Two Ages, that:

"Technology will make available to the leaders of major nations, techniques for conducting secret warfare, of which only a bare minimum of the security forces need be appraised.....techniques of weather modification could be employed to produce prolonged periods of drought or storm." 

Dystopian visionary quotes from Brzezinski's 1970 book:

"a system that would seriously impair the brain performance of very large populations"