Does less lead exposure mean less violence?

Has exposure to lead anything to do with criminal behaviour? Yes, says a research paper.

It says that the declining violence across the US since the 1990s has less to do with the efficiency of criminal justice system and more with reduced lead in the atmosphere.

The study, the findings of which have been published in Chemical & Engineering News, details the mounting data that suggests taking lead out of gas and paint has played a critical role.

Lauren K. Wolf, associate editor at C&EN, explains that violent crimes had reached an all-time high in the US in the early 1990s. But by the end of the decade, the homicide rate had plummeted by more than 40 percent.

Lead emitted from car exhaust and coated building walls until it was banned from petrol and paint in the early 1970s.

The article points out that babies born post-ban were exposed to far less lead. Twenty years on, those babies became young adults who committed fewer crimes than their predecessors.

Recent studies have blamed lead for lowering IQ and causing attention problems and antisocial tendencies.