A toxic weedkiller stays on Australian farms after a 30-year review, because paraquat is cheap, effective and hard to replace, but the decision leaves a bigger question about how long farmers can depend on it

Now picture yourself being on a large broadacre farm in rural Australia, looking at fields full of yellow wheat with the sun shining in the morning. For someone who sees the farm from the outside, everything seems perfect and natural.

However, beneath the surface is a complex system of modern chemistry. For many years, Australian farmers have used a herbicide to help manage weeds.That helper is paraquat, a powerful herbicide that has survived a long regulatory review. The Australian Pesticides and Veterinary Medicines Authority recently finalised a decades-long evaluation of this herbicide. Instead of issuing a total ban, the regulator kept the chemical on the market with new safety conditions.

It has drawn strong reactions from medical and environmental groups.An investigative article in The Guardian has shed light on this extremely complex problem. According to this investigative piece, the decision has drawn criticism from some scientists and Parkinson's advocates, who point to studies linking paraquat exposure with Parkinson's disease. The report stresses that this chemical has been entirely outlawed in over 70 other countries because of the associated health fears.

The economic driver of no-till agricultureTo truly understand why regulators refused to join international bans, you have to look at the unique history of modern crop production. Back in the middle of the last century, traditional farming relied heavily on mechanical ploughing to rip up weeds before planting new crops. While ploughing was effective at clearing fields, it was a slow process that tore up the delicate topsoil, leaving the land incredibly vulnerable to brutal wind and rain erosion.When paraquat entered the global market, it offered an incredibly attractive alternative known as no-till or conservation farming. Instead of spending days driving heavy tractors back and forth to mechanically churn up the earth, a farmer could simply spray a field with this fast-acting compound. Within hours, the green weeds would wither and die, while the structural integrity of the soil remained completely intact.

This method completely revolutionised the industry, allowing crop managers to conserve vital moisture in drought-prone areas and drastically cut down on fuel expenses.This perspective is closely mirrored by 9News, which details how the national regulator reviewed hundreds of scientific papers and long-term data sheets before ultimately concluding that the evidence failed to establish a definitive, direct causal link between approved agricultural use of the chemical and the onset of debilitating neurological disorders.

While the decision may ease concerns for grain, cotton and sugar producers, it also introduces new handling requirements for Australian farms.Over the years, this chemical became the ultimate economic asset for large-scale operations managing grains, sugarcane, cotton, and horticulture. It works quickly on contact and is valued for its short residual activity. Because patent protections expired long ago, the chemical is remarkably inexpensive to manufacture and purchase compared to newer, more technologically advanced alternatives.

For a modern family farm operating on razor-thin profit margins, the financial math was incredibly simple, as losing access to such a cheap tool could mean the difference between a profitable harvest and absolute financial ruin.

A lingering question of health and long-term survivalDespite its undeniable economic benefits, the decision to keep this powerful chemical legal has re-ignited a passionate, emotionally charged debate regarding human safety.

Medical experts, environmental organisations, and prominent neurological groups across the globe have spent years presenting data that connects long-term exposure to the chemical with a significantly higher risk of developing Parkinson's disease.

While the regulator noted that its multi-decade review did not establish a definitive causal link between the product and the neurological disorder, the agency still acknowledged that the status quo could not continue.The new guidelines will significantly alter how the product is handled on the ground. The authorities are entirely phasing out the use of hand-held backpack sprayers, forcing operators to transition to completely enclosed mechanical mixing and loading systems to minimise the risk of skin contact or inhalation. According to The Guardian report, they are also cutting down on the total application volume permitted per hectare, slashing maximum application rates from 1,150 grams per hectare down to a strict 231 grams per hectare, unless technology-assisted spot-spraying is used.While this new legislation offers some reassurance to the concerned public, it also opens up a completely new realm of problems for the agricultural community. Small family-based farms will now have to spend thousands of dollars on acquiring specialised machinery in order to be able to use a product that previously could be handled with much simpler tools. It raises uncertainty for the industry. In light of international pressure and weed resistance, some observers see this as only a temporary reprieve.

Australia still faces pressure to find safer weed-management options.