Australia’s grains industry has a 99.2 per cent compliance rate with national maximum residue limits (MRLs) based on thousands of samples tested for chemical residues in both domestic and export markets.

“That’s a fantastic result when you consider how much grain is grown and moved each year,” says Jenna Garwood, who is the assistant director of the National Residue Survey Plant Programs for the Australian Department of Agriculture, Fisheries and Forestry.

Ms Garwood says these results, averaged across all tests in the 2021-22 year, reflect on the professionalism and good practices in the industry and continue the excellent trend from previous years.

She notes that contamination of grains is not the sole province of growers, with residues from grain treatments in bulk storage facilities and contamination in transit both possible sources of MRL breaches.

Flutriafol contamination

Several years ago, the National Residue Survey identified flutriafol contamination as an issue. Sources of contamination were traced back to the storage or transport of wheat seed and fertilisers treated with this fungicide.

“In 2017-18 we had nine detections, and it was an ongoing problem,” Ms Garwood says. “But there has been a lot of outreach and education within the industry about good hygiene and good handling.

“We have seen continual improvements since then, down to zero detections last year.”

In 2021-22, more than 6500 samples were submitted for testing from bulk export terminals, container export packers, oilseed crushers, feed mills, flour mills, feedlots and food processors.

“The current results really show that growers are doing the right thing. The 99.2 per cent compliance is a phenomenal number in this business, when issues such as spray drift or seasonal conditions change the way plants metabolise chemicals that can all influence results in unexpected ways,” Ms Garwood says.

“These are all variables the industry is constantly working to address.”

Evolving tests

The tests undertaken as part of the survey evolve as new chemistry becomes available to growers, or new varieties are released that might respond differently to available chemicals. Testing also changes in response to seasonal conditions; for example, in wetter years testing ratios for fungicides or crop desiccants might increase.

Ms Garwood says the National Residue Survey team works closely with the National Working Party on Grain Protection, Grain Producers Australia, Grain Trade Australia and GRDC to address any emerging issues and trends and to keep growers informed.

More information: Jenna Garwood, 02 2722 2438