Lead poisoning ... Daphne Hare with her daughter, Stella, who has learning and behavioural problems / Credit: NEWS.com.au

According to the statistics published in the Medical Journal of Australia, one child suffers from lead poisoning every nine days in the mining town of Mt Isa, in Queensland.

Professor Mark Taylor, associate professor at the Macquarie University, who is also the co-author of the report says, the public health risk in the city is evident.

His report stated that the main source of environmental lead in Mt Isa comes from the historic and current mining and smelting operations.

The use of a purported lack of knowledge of the lead source as an excuse, he said is no longer a tenable response.

The study shows that the IQ of children exposed to elevated levels of lead was cut down by five per cent.

Prof Taylor said the effects can be observed on their behavior patterns, school scores, ADHD and lifetime consequences.

In 2008, the blood tests performed by Queensland Health revealed 11.3 per cent of kids aged 1 to 4 years old had dangerous levels of lead -higher than the standard guidelines.

Damian Scattini, lawyer for Slater & Gorden is representing seven families from Mt Isa whose children have allegedly developed poisoning and brain damage due to lead exposure.

The Xstrata and the state government were in denial about the issue, said Mr Scattini and that when compared with American guidelines, the safety standards at Mt Isa were weak.

Steve de Kruijff, spokesman for Xstrata said the company has always acted responsibly.

His statement said that Mt Isa has one of the most intensive air quality monitoring systems of any city in Australia that directs the smelters to shut down emissions that may potentially impact the community.

Xstrata is still running its Lead Pathway study, with the first phase of searching for land contamination, completed in July 2009, and the second and third phases assessing air and water contamination which will be completed in 2011.