Scientists are starting to find alarming links between children who are exposed to lead and violent crime later in life.

In the US, lead is increasingly viewed as a long-term public health risk, and now preliminary findings from an Australian study suggest areas with high lead pollution later experience high assault rates as lead-exposed children become adults.

Chad Hinds grew up in the New South Wales town of Boolaroo just 300 metres from the town's lead and zinc smelter.

Boolaroo had such high lead levels that smelter operators had to buy most of the houses in Mr Hinds's street.

As a child, he suffered from asthma and lived with the smell of the smelter day and night.

"It was just like a foul, off, yuck taste," he said.

In primary school he struggled to learn and started falling behind.

"Reading was the one I couldn't do. Every now and then they would get the whole class reading and I would be worried because I couldn't read," he said.

As Mr Hinds became a teenager his behaviour continued to deteriorate.

"I was just out of control. Mum would put AVOs [apprehended violence orders] on me because I was just a loose cannon," he said.

Mr Hinds later went to jail for breaching an AVO.

He now suffers from bipolar disorder and memory loss. With medication he is able to work and look after his eight-month-old son.

Mr Hinds acknowledges that other things have gone wrong in his life, but he is convinced he paid a high price for growing up next door to a lead smelter.

"My memory is hopeless now. I can't remember what I did three days ago. I know I went to work but what I done during the day I just can't remember," he said.

"It's affected me like that. It's definitely affected me. It's catching up with me as I get older."

Today, Australian health authorities aim to keep blood-lead levels in children below 10 micrograms per decilitre.

In 1991, children at Boolaroo primary school were given a blood lead test. Of those children, 84 per cent had levels above 10 micrograms.

Theresa Gorden, a former Boolaroo resident, says Chad Hinds was one of those children.

Chad Hinds says his exposure to lead is catching up to him. ( ABC TV )

"From memory Chad had a blood level of 29 micrograms per decilitre at the age of six or seven," she said.

Scientists like Sammy Zahran from Columbia University in the US are increasingly looking at lead as a potential cause of impulsive crime.

"I think the true cost of lead, we are only beginning to fully calculate. So this research into violence is only one of a long string of negative outcomes that epidemiologists and economists have noted," he said.

"As we begin to tabulate this loss, I think it will one day be understood as one of the greatest public health mistakes that we have committed."

Last year Mr Zahran completed a study exploring links between six American cities with high lead pollution and assault rates.

He found a consistent 20-year time gap between lead pollution and violent crime.

Professor Mark Taylor, an environmental scientist at Macquarie University, has now begun Australia's first study comparing suburbs with high lead air pollution levels and local crime rates.

Professor Taylor says his research also indicates there is close to a 20-year time lag between the peaks in lead air pollution and peaks in the rates of assault.

Boolaroo: Lead air pollution peaked in 1988. The assault rate peaked 21 years later in 2009.

Lead air pollution peaked in 1988. The assault rate peaked 21 years later in 2009. Earlwood, Sydney: Lead air pollution peaked in 1982. The assault rate peaked 20 years later in 2002.

Lead air pollution peaked in 1982. The assault rate peaked 20 years later in 2002. Port Kembla: Lead air pollution peaked in 1979. The assault rate peaked 20 years later in 1999.

Lead air pollution peaked in 1979. The assault rate peaked 20 years later in 1999. Lane Cove, Sydney: Lead air pollution peaked in 1978. The assault rate peaked 21 years later in 1999.

"The locations we are looking at are, for example, Sydney, Rozelle, Earlwood, Boolaroo, the old lead smelter, Port Kembla as well, so we have been able to extract reasonably good records for those locations," he said.

"We are not saying that it's a one-to-one relationship, what we are saying is that lead exposure is associated with violent activity.

"It pre-disposed those children, it puts them on a trajectory where they may, along with other factors in their life, it may then pre-dispose them to violent activity later on in life."

But critics of population studies say the research is too broad.

Professor Wayne Hall from the University of Queensland says there is no evidence the young children exposed to lead are the same people who go on to commit the crimes.

"Ideally you need information at the individual level showing that for individuals there is a connection between lead exposure and the likelihood of engaging in violent crime," he said.

"It's certainly an hypothesis that deserves to be taken seriously and further investigated. It's probably too early to be drawing strong conclusions that the relationship is causal."

But Professor Taylor says the impacts of exposure to lead in Australian children cannot be ignored.

"We know that crime is associated with lower IQ and we are trying to look at the relationship between the two," he said.

"We are not saying that lead is the only driver of that relationship, we are saying that in the Australian context it has never really been considered."