Farmers and agronomists say proposed regulation changes to paraquat use from the Australian Pesticides and Veterinary Medicines Authority (APVMA) will have heavy negative consequences for them. 

A review by the APVMA released on 30 July says the authorising body does not support paraquat use in fallows or for spot spraying. 

It also recommends reducing paraquat use via boomspray from 2.4 litres per hectare each season to 0.9 litres. 

“It’s a major tool in managing a Roundup-resistant weed. It will have a huge impact on our farming systems,” Coonabarabran agronomist James Fleming said. 

“In the summertime, we use a lot of fallow spraying to keep the paddocks clean.”

Mr Fleming said farmers use paraquat in combination with other chemicals such as Roundup or glyphosate to combat weeds such as resistant ryegrass. 

Coonamble farmer Tony Single said the changes would mean he wouldn't be able to control weeds effectively on his farm. 

"We would either need to reintroduce tillage in the short term or try to find another option.

"I think everybody's quite worried about what it means for the longevity of sustainable cropping in our region."

The proposal comes off the back of the APVMA's Paraquat Review Technical Report assessing the product's risk to humans and the environment. 

Under the body's regulations, products must be unlikely to unduly harm humans, animals or non-target plants. 

Mr Fleming said that he had not heard of anyone in his area who sustained injuries from paraquat. 

“Safety-wise, we’ve come a long way with handling chemicals. We’re not tipping it into jugs like people used to measure it out.

"We follow all the safety requirements on the label.”

Mr Fleming said there are no viable alternatives and if the regulation changes were to come into force it would mean farmers would have to cultivate more. 

“It creates a lot of issues with protecting our soil from erosion and helping water infiltration,” he said. 

The draft proposal is open for public comment until 29 October with a final decision expected in the first quarter of next year.

The APVMA also recommended cancelling the registration of two diquats named AQ200 Aquatic Herbicide and WaterTreats Aquatic Weed Killer.