Bioremediation to keep atrazine from waterways

Farmers around the world are expected to benefit from the successful trial of an enzyme that breaks down the herbicide, atrazine, in run-off water. 'When we added the enzyme to a holding dam filled with run-off contaminated with atrazine, more than 90 per cent of it was removed in less than four hours,' says CSIRO Entomology's Dr Colin Scott.

'Atrazine is a widely used and extremely useful herbicide but, depending on its use, can lead to residues that persist in water for sometime after application. Undesirable residues in water have led to restrictions on the use of atrazine in the EU and USA.

'The enzyme we have developed will reduce the potential for off-farm water contamination by atrazine and this should help provide continued access to it for farmers,' he says.

The successful trial was held in the Burdekin sugar growing region near Ayr in Queensland and the results are very promising for reducing contamination in run-off that reaches the Great Barrier Reef.

Collaborators in the trial were the Queensland Department of Primary Industries and Fisheries, James Cook University and the Great Barrier Reef Marine Park Authority.

The DPI and F's Rob Milla, who organised access to the trial farms and assisted in sample collection, is also pleased with the results.

'These initial field test results are very encouraging and our next steps will be to apply the enzyme in standard operating situations to ensure there are no impediments, from a farmer perspective, to its easy and effective use,' he says.

CSIRO Entomology's General Manager, Business Development and Commercialisation, Cameron Begley, says the enzyme also works well against a range of other triazine herbicides and, once in commercial production, would benefit farmers and water consumers wherever triazines are used.

The CSIRO bioremediation team is now focusing on improving the production and application of the enzyme, to provide farmers and water consumers around the world with a cost effective bioremediation product to address triazine contamination.

'To facilitate this, CSIRO is actively seeking commercial partners to collaborate with,' Mr Begley says.

CSIRO's search for the enzyme began with a search for bacteria that 'fed' on atrazine. Once identified, the team isolated the enzyme that broke down the chemical into non-toxic components and developed it to make it a product suitable for low-cost production and delivery into a range of situations.