The ‘link’ between lead pollution and violent crime

Could the removal of lead be behind a fall in violent crime decades later? Research suggests there is a connection.

Motorway trafficRui Vieira, PA Wire

Various reasons have been given as to why violent crime has dropped in big cities since the early 1990s from tough policing, drug use or even recessions.

But local, national and international research suggests a link between the amounts of lead that children were exposed to and violent crime – with experts warning exposure to lead can damage the brain.

The lead link with crime

Lead emissions from vehicle soared through the early 1940s through to the early 1970s.

But emissions then fell as unleaded fuel was introduced, along with tough environmental rules and catalytic convertors.

Over that time, crime rates rose in the 1960s through to the 1980s before falling back in the 1990s – a time lag of around 20 years. And research showed the pattern repeated across the world, including in Britain.

And where leaded fuel was phased out more slowly, crime dropped more slowly as well, according to studies highlighted on US website Mother Jones.

Reducing lead emissions will benefit society

A recent study looking at crime and lead emissions in several US cities between 1950 and 1985 has also found a link between the two – albeit it with a lag of 22 years.

But measures to reduce children’s exposure to lead may see many benefits for society two decades in to the future, including lower violent crime.

Howard Mielke, professor at pharmacology at Tulane University in New Orleans, was one of the authors that examined the situation in his own city.

Speaking on BBC Radio 4’s Today programme, said his investigations into the issue began with looking at lead in the environment and children’s achievement at school.

“More and more we started to realise that the amount of lead in the environment, especially within the soil, was particularly strongly related to both learning problems and then violence,” said the academic.

And he has produced maps of New Orleans as a way to look at the issues, adding the local police were using them.

“They find them very predictive of where the highest crime rates are being found in the city.

“There is a very strong association between criminal activity and the environment of different parts of the city,” said Professor Mielke.

Alastair Hay, professor of environmental toxicology at Leeds University, said he found the research “quite convincing” – although more work needed to be done.