The discovery of a Parkinson’s disease cluster in a barley, chickpea and lentil farming region of north-west Victoria has prompted calls for further research into a potential link between pesticides and the disease.
Australia’s federal pesticide regulator has backed calls from researchers for further study into a potential link between the use of pesticides and increased risk of Parkinson’s disease.
Australian Pesticides and Veterinary Medicines Authority (APVMA) spokeswoman Dr Raj Bhula told SBS the organisation believed further research was justified, but said there was not any: “clear-cut evidence that links the two together”.
The call comes following the discovery of a Parkinson’s disease cluster in a barley, chickpea and lentil farming region of north-west Victoria.
Researchers from Monash University and the Florey Institute of Neuroscience and Mental Health found elevated rates of the disease in four neighbouring council areas.
In Buloke, the prevalence was 78 per cent higher than the Victorian average. It was 76 per cent higher in Horsham, 57 per cent higher in Northern Grampians and 34 per cent higher in Yarriambiack.
The study’s co-author Darshini Ayton says the results came as a surprise.
"We were quite shocked that this cluster existed ... we didn't expect to find a cluster of four LGAs neighbouring each other with significantly higher rates of Parkinson's disease," she said.
The research team cross-referenced data on Parkinson’s drug consumption in each council area, controlling for age, with Bureau of Statistics data on agricultural output.
Ms Ayton said the research did not prove pesticides used in pulse production caused Parkinson’s disease, but did suggest a correlation.
She said her message to pulse farmers in the area was “don’t panic, just yet”.
“But I think you can understand the anxiety that this type of research is going to cause.”
“Really we're very much saying we need further support, we need further research to understand these causal mechanisms."
Parkinson’s Victoria is calling for further research to determine if pesticides do cause the disease in humans.
The study is not the first to investigate a potential link. Researchers overseas have injected rats with the pesticide Rotenone and induced Parkinson's-like symptoms.
Dr Bhula said the APVMA looked in to those experiments at the time but chose not to ban Rotenone, which remains legal in Australia, because “the doses that were being given to the rats were much, much higher than any sort of exposure that somebody would get from applying the registered product”.
Matthew Cossey, CEO of agricultural chemical industry body CropLife Australia, said pesticides were safe as long as they were used in accordance with instructions on the label.
"It’s important not to mislead the public based on an untested correlation. Too many cases of making assumptions based on correlation have led to obscuring the real cause of problems," Mr Cossey said.
"Human health and safety of crop protection product use is the number one priority of the plant science industry, from the farmers who use them directly to the end consumers of produce. No one takes this issue more seriously than the industry itself."
A spokesman for the Victorian Farmers Federation said the organisation would look at the issue if there were further research developments.
“There’s not much we can say, other than that we are hoping they’re not just focusing on chemicals,” the spokesman said.
Tim Edgecombe, CEO of agricultural industry body Pulse Australia, said he would not comment until further research was conducted, other than to say correlation did not prove causation. Among Pulse Australia’s members is Bayer CropScience, a leading manufacturer of fungicides, insecticides and herbicides.
Ms Ayton said it was possible pesticides were the primary cause of Parkinson’s disease.
"I do think it is possible, and particularly because we can show that in animal models, but we don’t want to be able to say that this research is showing that, at this stage," she said.
The researchers will release their full report later in the year.