Active thread on the same subject.
Reported.
Sorry. 
Interesting.
As an aside I knew a kid in high school. His science project was measuring lead deposits alongside a major (but two lane so not too major) local highway. But it WAS out in the boonies so local contributions were fairly minor. The local chem professors who were helping with how to make the measurements were fairly sure the levels would be nearly too low to detect with the crude method he would have at his disposal. But, the levels he found were high enough that they suspected he screwed something up!
Anyway, interesting article.
The other other compelling item from that cite,
CMC
Lead paint also seems to show a strong correlation.
Could it be that medical technology has improved such that in 2000 a gunshot that would have been fatal in the ER (so not counted in the treatment & release statistic), but in 2010 that life was saved and then admitted to the hospital?
Maybe they did not go to the regular streets, but to Wall Street.. 
Isn’t every successive generation the youngest one? 
That may play a very small part to play but those crimes would still be assault and violent crime including assault is down across the board.
IMHO there is no single cause of the drop but the reduction of lead exposure is one of the many factors that have helped reduce violence in general.
But I agree it is probably paint because the violent crime rate in the US hit an all time historical low in about 1950, almost 40 years after the introduction of the car and at least a generation after they were common.
Actually, as a resident of Southern California I remember many days 40 or so years ago when the sky was a shade of yellowish-brown, and breathing was difficult and at times painful. The fact that those days are all but forgotten is sufficient reason for me to appreciate the usefulness of the government’s activities in that regard. If it lowered crime, great. If not, we’re still ahead.
Pb in gasoline per capita in 1958 was four times the level in 1937.
I know this because I looked at the linked articles instead of assuming that an objection I thought of six seconds after hearing about a theory was just too clever to have been considered by people that had spent days months or years studying that same theory.
A little follow-up.
People keep saying this, but I have yet to see anyone effectively debunk it. (As someone born right in the peak period for lead and mourning the probable brain damage I incurred, I would only be too happy to see a thorough refutation if one were possible.)
“I have yet to see anyone effectively debunk it” just isn’t a very good proof of anything. There is clearly a correlation there, and it seems to hold not just across time but across various countries. That’s not a definitive proof. I’ll wait for a few more scientific studies of the matter and a statement by some official scientific body which looks at many different studies in order to make a more thorough report.
I’m not sure how much this alone tells us. Low-income people disproportionately live in contaminated neighborhoods. They’re contaminated with lead, and they’re contaminated with crime, but that doesn’t show that one caused the other. For instance, nobody would say that lead contamination causes old cars and payday lenders, even though the neighborhood-level correlation is probably solid.
There also appears to be a well-documented biological mechanism.
That is correct, but the issue here is that changing the burden of environmental lead changes the crime burden. Without any changes in income. The correlation seems to hold over a wide variety of variables, including income.
Grim Render, my point was that there not being an effective debunking is not, by itself, sufficient to disprove it. Lots of times someone will throw out out a single interesting fact suggesting that X causes Y and then demand a debunking of it. That’s not necessary. The theory that lead in gasoline causes crime has much more evidence for it, but it’s not quite at the level where we can say that it’s generally accepted. I’m saying that we should continue to think about this and do studies on it. Yes, it looks good at the moment. No, it’s not quite at the level of a generally accepted scientific theory. That was my point.
So two of the best explanations for the crime drop are environmental regulation and abortion. Conservatives getting trolled.
Next topic where everyone is shocked that pollution actually has negative effects: endocrine disruptors?
"Lead and Crime: Why this correlation does mean causation."by Rick Nevin. Note, this is a link to a pdf.
Thank you. I feel vindicated.
“Hey, here’s a trend. Hey, here’s another trend. I’m convinced they’re related without doing any research!”