10 Jan, 13 | by Iain Brassington
People who listen to Today may have heard an article in the prime 8:10 slot on the 9th about the correlation between a drop in the use of leaded petrol, and a drop in violent crime rates. (Mother Jones actually beat the BBC, having published a piece on the same research last week: I meant to post something then, but was buried by other stuff.)
The nub of the story is this: that violent crime has been falling in the past few years, and though this pattern seems to lag about 20 years behind a fall in the use of lead in petrol, the fit is pretty good: a decline in leaded petrol predicts a decline in violent crime by about two decades – which is just about the time that we might expect would elapse between the formation of the brain and the highest likelihood of violent behaviour in humans. Neat. The Mother Jones piece provides lots of links to the relevant research – links to this (from 1999), and this (from 2007), and this (from 2012).
If the lead hypothesis is sound, it seems to be ethically interesting in a couple of ways. For one thing, it opens the way to at least some antisocial behaviour to be seen as being symptomatic of a deeper public health problem. That’s interesting enough as it is, but – admittedly – it might be little more than interesting, on the grounds that leaded petrol is pretty much a thing of the past anyway (Wikipedia says that, as of 2011, leaded petrol was widely available only in 7 countries).
But the other way in which it’s interesting has to do with arguments about so-called “moral enhancement”. more…