til #GenerationX (Americans born about 1965-1980) were uniquely affected by #lead exposure in their childhood (through leaded gasoline). And we know now that the #developmental and #neurological consequences of lead exposure can be really dramatic. (But I had no idea that the cut-offs are so clear!)
Those Americans who are about 50-60 now went through some tough brain poisoning as kids. May explain certain things.
(via @calebwatney@.com)