'Wand' will highlight environmental risks

Australian scientists are developing a "˜magic wand' to find out how dangerous soil and groundwater contamination is.

Researchers in the CRC CARE (the Cooperative Research Centre for Contamination Assessment and Remediation of the Environment) are developing special sensors to analyse the toxic stew of chemicals under old industrial sites "“ so they can be safely treated and the land made safe for future use.

"We're developing sensors that will give us a much better idea of the pollution present over time," Associate Professor Jack Ng of CRC CARE and The University of Queensland said.

"These sensors reveal the concentration of the contaminants and their potential effect on humans, plants and animals. They will enable us to search for specific contaminants that are of concern, or to diagnose mixtures of pollutants."

In some cases, the sensors will consist of special microbes tuned to light up if they encounter particular contaminants, or show toxic stress by changing shape, altering their coats or even dying.

"We've already developed bugs that light up when they come in contact with a certain contaminant. You can do it by inserting a lux (light-generating) gene into the microbe or by using a fluorescent probe," Ng said.

One of the approaches the team is developing is to put the sensors on a rod "“ referred to as a "˜magic wand' "“ which can be stuck in the soil or water and provide an on-the-spot readout on the presence of toxic contaminants. This will dramatically reduce the time needed to send samples to a laboratory for analysis.

The managing diretor of CRC CARE, Professor Ravi Naidu, said risk assessment was the critical first step in making society safe from the contamination caused by past decades of industrial development.

"In order to treat these sites effectively and economically, we need to know exactly what's down there," he said.

"The tools being developed by CRC CARE's Risk Assessment program will help us to do just that."

Ng said the new sensors would be quick, low cost and easy to use. In many cases they would provide an answer in the field "“ a huge help to site developers who suddenly discover they had a contamination problem to deal with.

05/10/2006