Gone without a trace?

When does a micronutrient become a contaminant? How much can our native species handle? Are the risks to human health fully understood? And what can we do to clean up our land and water?

More than 300 international delegates travelled from 45 countries to meet in Adelaide recently, to discuss these and many other important questions facing policy-makers and regulators around the globe.

It was the first time the International Conference on the Biogeochemistry of Trace Elements (ICOBTE) had come to Australia. For the past two years CSIRO Land and Water has been working closely with The International Society of Trace Element Biogeochemistry to prepare for this, the eighth in a highly successful series.

Chair of the local organising committee, CSIRO's Dr Mike McLaughlin said, "The 8th ICOBTE promises to be the premier industry-wide gathering of environmental researchers and other professionals from the agriculture, fertiliser, health and mining sectors to be held in Australia this year."

"There were more than 200 oral presentations, including a very interesting and impressive selection of plenary and keynote papers. We also introduced a number of new session topics, to incorporate the science of trace metals in aquatic environments, a focus on trace elements for human nutrition, and sessions devoted to the geochemistry of trace elements in landscapes," he said.

Trace elements are relatively rare in the Earth's crust (like the heavy metals mercury, lead and cadmium, and other elements like selenium and arsenic), but can accumulate with rapid urbanisation and industrialisation.

Dr McLaughlin explained: "Many trace elements are essential for life. But you can have too much of a good thing " at high concentrations, most of these elements are really very toxic. They can also build up in the food chain. So we need to be really clever about managing risks and developing appropriate and cost-effective remediation technologies."

South Australian Environment and Conservation Minister John Hill said: "Understanding how trace elements behave in the environment is tremendously important, especially in this part of the world.

"Many people in our region are affected by trace element deficiencies in soils " South Australia has a long history of use of trace element fertilisers, and indeed significant pioneering work in identifying and correcting trace element deficiencies in crops and livestock was undertaken here.

"The resulting debate from the gathering will be of great interest to governments and natural resource management agencies."

Item provided courtesy of CSIRO