Researchers have warned that the dangers of large lead smelters are going unchecked.

Environmental scientists are calling for better regulation of air-borne pollutants near the Port Pirie smelter in South Australia and at Xstrata's Mt Isa lead facilities in Queensland.

Professor Mark Taylor of Macquarie University has been conducting a range of studies on the pollution and effects of the plant on the nearby population.

He says that the licence arrangements for Nyrstar's lead smelter fail to stop significant toxic emissions such as arsenic, cadmium and sulphur dioxide.

Arsenic is a cancerous substance which causes skin legions and respiratory issues; cadmium damages the brain, kidneys and skeletal system; and sulphur dioxide is known to affect breathing as well.

Professor Taylor says the smelter stack is the key source of arsenic, cadmium, lead and sulphur dioxide at Port Pirie, but the SA Government has allowed its operators to put industry profitability ahead of safe practice.

He has also criticised the methods used by governments to measure blood-lead levels.

He says governments typically only report recent levels, rather than the peak-time extremes.

Professor Taylor’s most recent examination of pollutants and risks in a number of mining and smelting towns are published in the journal Aeolian Research.