The Australian Pesticides and Veterinary Medicines Authority announced its final decision on Tuesday to continue allowing the use of the herbicides paraquat and diquat in Australia. The authority will impose stricter conditions on their use to reduce exposure risk for farm workers, birds, and mammals.

Scott Hansen, Chief Executive of the Australian Pesticides and Veterinary Medicines Authority, stated that a review of scientific papers and long-term data did not establish a causal link between paraquat and Parkinson's disease. However, he also stated there was evidence regarding potential impacts on farmworkers from exposure and impacts on birds and mammals. Hansen detailed new limitations, stating, "Both chemicals remain available for use with new restrictions on application rates and permitted uses." He added, "To protect users from acute exposure, new restrictions will phase out backpack sprayers and require enclosed mixing and loading systems for all uses, and enhanced personal protection equipment." He further specified, "Overall, the maximum rate of application on paraquat and diquat will be 231 grams per hectare, when it was previously 1,150 grams per hectare." A higher application rate will be permitted for technology-assisted spot spraying when limited to 30% of a total area.

Olivia Nassaris, CEO of Parkinson's Australia, expressed concern regarding the decision. "Seventy countries have banned the use of paraquat," Nassaris said. She added, "Are the lives of Australians less valuable?" Independent Senator David Pocock also commented on the decision, stating, "This seems like yet another example of vested interests winning out over community interest."

Paraquat is banned in approximately 70 countries, including the European Union and the United Kingdom, both of which banned it in 2007. The US Environmental Protection Agency reviewed paraquat in 2021 and allowed its ongoing use with stronger controls. New Zealand also allows paraquat to be used. Australia uses a risk-based assessment for licensing chemicals, requiring actual risk to be established.

Paraquat is used in broad-acre farming for crops such as grains, sugarcane, cotton, and horticulture, where it is used to control grasses and weeds and to remove foliage from crops like cotton and potatoes before harvest. Syngenta Australia stated that it is assessing the impact on its product portfolio under the restricted conditions. The Australian Pesticides and Veterinary Medicines Authority declared paraquat a priority for reconsideration in 1994, settled the work program for its review in 2015, and released an interim report on paraquat in 2024.