I saw a video of where they still mine it in Russia. They people there don’t even think it causes cancer.
I thought the speculation in Freakonmics was the correlation between legalized abortion and reduced violent crime rates.
Reduction in environmental lead, including from gasoline, certainly has reduced from EPA laws in the 70s, including paint, kids toys, and piping and the like. So surely there have been some positive health effects? I have also seen people speculate that the mass incarceration program is what reduced violent crime. Or the increase in the number of cops.
The truth is probably an amalgamation of factors, but I do think reduction of environmental lead had a hand in the decline of violent crime since its height in the 90s.