Chemical banned around the world could be linked to incurable illness in Australia

There’s mounting evidence that a highly popular weed killer used on farms across the country could be linked to the progressive nervous system disorder, Parkinson’s disease.

The chemical paraquat is so toxic that its use is banned in 74 countries around the world, even in China where it’s produced - but not here in Australia and patients, doctors and experts of the disease are asking why.

This is a battle not between farmers and doctors, but between patients with Parkinson’s and the Australian chemical regulator.

For Sandi Gerschwitz, moving is life - she takes boxing classes, goes to personal training sessions, goes cycling, regularly hikes and has even conquered one of the highest peaks in the world in Nepal.

To the average eye, it’s impossible to believe she has Parkinson’s, but one of the cruel ironies of the disease is that basic movement can be near-impossible.

For all her fitness feats, Sandi struggles to get from her armchair to her desk.

“You’re telling your body to actually move, but it’s like no one’s home,” Gerschwitz told A Current Affair reporter Davina Smith.

Those muscle freezes are one of the many symptoms of Parkinson’s - a condition associated with the elderly, but Gerschwitz is just 52.

“Walking is difficult for me, but I can do stairs,” Sandi said.

“I just happened to say to one of the allied health people, ‘Why is there so many people that my age and maybe a little bit older coming down with Parkinson’s?’” Gerschwitz recalled. 

“And this person said to me at the time, said, ‘Well, yeah, it’s chemicals in the farming.’”

Gerschwitz grew up on a wheat property in South Australia, where a herbicide called paraquat was widely sprayed across the district to kill weeds.

Paraquat has been strictly banned or restricted for decades in more than 70 jurisdictions, including in the UK, across the European Union and China - most recently in the US state of Vermont where an official ban will be implemented in November this year.

Yet three years ago, paraquat manufacturer Syngenta shared a video online featuring Western Australian wheat farmer and Grain Producers spokesman Andrew Wiedmann, who showed what he had to do these days to stay safe while using it.

“If you’re following the guidelines and you’re doing things properly, it is very safe to use,” Wiedmann said in the video. 

“We just put it in the tank through its system and we don’t come exposed to it.”

The timing of the video was crucial; the Australian Pesticides and Veterinary Medicines Authority (APVMA), which decides what products are safe for use, was considering whether paraquat should be banned here too.

“The thought of not having products like paraquat in our rotation to support what we do, it’s just going to be a real problem for us,” Wiedmann added.

Paraquat is used on golf courses and on farms growing wheat, barley, chickpeas, soybeans and potatoes. 

It is a cheap and effective way to kill weeds without disturbing moisture content in the soil. It kills everything it touches and is often sprayed just before seeds are planted, clearing the paddock.

Because of its toxicity, users need a licence to buy and store it, must wear strict PPE, and can only spray it using an enclosed mixing and loading system.

“We are the most pro-farmer organisation you can possibly find, because we are trying to keep farmers healthy and safe,” Olivia Nassaris, CEO of Parkinson’s Australia, said.

She and Professor David Blacker are fighting for change.

“I think we need to plan the ban and get the people involved that can make the difference,” Blacker said. 

“And I think the economic impact of altering farming practices needs to be offset by the healthcare costs.”

For Blacker, it’s personal. 

After decades as a neurologist diagnosing patients with Parkinson’s, he himself developed the disease. 

He links it directly to his childhood growing up in Western Australia’s wheatbelt.

“If farmers have been misled to think that they’re working with something that’s safe, not doing them or others harm, then you can understand why they’ve got this view that it’s essential,” he said.

International studies have found people with prolonged exposure to paraquat spray - through their skin, in the air, or through contaminated water supplies - are three times more likely to develop Parkinson’s.

The World Health Organisation has raised the risks of its use, but the Australian regulator has not budged on its position.

“There’s just no compelling evidence that there’s actually a causative link,” APVMA CEO Scott Hansen said last month, when the authority published its 30-year, 234-page review of paraquat.

No Australian neurologists were consulted during the review, but the main study the APVMA relied on to form its conclusion was a 2021 report funded by paraquat manufacturer Syngenta.

While the APVMA says it makes evidence-based decisions, there are calls for decisions about paraquat to be made by someone entirely independent.

“I don’t think the APVMA can be trusted to make these decisions,” Nassaris said. 

“I don’t think they’re independent enough.”

The APVMA is primarily funded by a cost recovery scheme, charging chemical companies a levy to register and sell their products.

“Parkinson’s incidence is set to triple by 2050,” Nassaris warned. 

“That is going to put a huge strain on our health system and our economic system.”

Shine Lawyers is currently conducting its own investigation separate from the APVMA. 

Practice leader Sarah Thompson is asking patients with Parkinson’s who may have been exposed to the chemical to contact them.

“Most of the stories we’ve heard so far are from people who worked on agricultural places of employment, so farms, golf courses, anywhere basically where there’s weeds and where they need to spray for those weeds,” Thompson said.

Despite the daily struggle and the looming legal battles, Gerschwitz remains resilient.

“You just live with it, you just get on with it,” she said. 

“It’s my life, it’s what I have to deal with. Everybody has something to deal with. So you just, yeah, keep on going.”

The APVMA stands by its decision to allow continued paraquat use, telling us safety, not industry funding, drives its approvals process. Here’s their full statement on the matter:

• The APVMA is an independent statutory authority responsible for assessing and regulating agricultural and veterinary chemicals in Australia under the Agvet Code.

• APVMA decisions are made independently and are based on the available scientific evidence, Australian use patterns and whether products meet the statutory criteria for safety, efficacy, trade, and labelling. If the APVMA is no longer satisfied that a labelled use meets the statutory criteria, it must remove, vary, or restrict that use.
• Fees and levies collected under cost-recovery arrangements fund the operation of the regulatory system, they do not determine regulatory outcomes.

• Cost recovery is an Australian Government policy applied to most regulatory bodies, including those that assess or approve therapeutic goods, financial services, aviation, maritime and communications activities. It does not affect the independence of decision-making.
• The APVMA considers all relevant available information as part of its assessments, including published scientific literature, studies provided by registrants or applicants, international regulatory assessments, and stakeholder submissions. All evidence is assessed for quality, relevance, and weight before it is relied on.
• Following a 3-month public consultation, each submission was considered in detail prior to making the final regulatory decision. How the APVMA considered each submission, including a specific submission focused on neurotoxicity are published on the APVMA website.
• Australia’s agricultural and veterinary chemical regulatory framework is risk-based. This means the APVMA considers both the inherent hazards of a product and the likelihood and level of exposure under approved Australian conditions of use.
• Where risks are identified, the APVMA may manage them through enforceable controls, including label instructions, use restrictions, personal protective equipment requirements, application controls, training requirements, withholding periods, or changes to approved uses.
• The final regulatory decision on paraquat requires closed mixing and loading systems for all uses, enhanced personal protective equipment and removes the use of backpack spraying from product labels.
• Many uses, at higher application rates, have also been removed from product labels due to environmental risks.
• Paraquat is a Schedule 7 poison in Australia and is subject to strict regulatory controls. The APVMA’s focus is on whether products can continue to meet the statutory criteria under Australian conditions of use, including with strengthened risk-management measures that are published on the product labels.
• The APVMA sets national regulatory requirements including product labels that must be followed, while state and territory authorities are generally responsible for compliance with use requirements in their jurisdictions.
• The APVMA will continue to consider relevant scientific evidence, international regulatory developments, and stakeholder submissions in accordance with its statutory responsibilities.

Full statement from the Australian Centre for Disease Control:

The Australian Centre for Disease Control takes potential public health risks seriously and continues to monitor emerging evidence.

The Australian Pesticides and Veterinary Medicines Authority (APVMA) is the independent statutory authority responsible for assessing and registering agricultural and veterinary chemicals for supply and use in Australia.

Decisions about banning or restricting chemicals are a matter for APVMA.

APVMA sits in the Agriculture, Fisheries and Forestry portfolio.

Questions regarding APVMA’s independence or funding model should be directed to that portfolio.