Australian regulators have proposed allowing up to 500 times more residue of a controversial pesticide on some berries, although products containing the so-called “forever chemical” must warn that it is suspected of damaging the unborn child.
The Australian Pesticides and Veterinary Medicines Authority (APVMA) said the changes for the pesticide isocycloseram would pose no risk to human health and berries would remain safe for consumers because exposure levels would be well below those capable of causing harm.
A spokeswoman said the limits relied on conservative assumptions and many layers of built-in safety margins to protect consumers.
“A single reference to an amount or level (such as ‘500-fold’) can be misleading as it does not reflect those compounded degrees of protection,” she said.
However, the proposal has sparked a backlash from environmental and health advocates who argue the pesticide has not been subject to enough independent safety testing after Australia was the first country in the world to approve it for use five years ago.
Studies submitted by isocycloseram’s manufacturer, Syngenta, have linked it to testicle degeneration, lower sperm counts and liver damage in rats.
A study reviewed by Australian regulators also revealed birth defects in the fetuses of pregnant rats fed high doses of the chemical.
Its approval in the United States is the subject of a legal challenge by environmental groups who argue the US EPA did not factor in the risks to children and developing fetuses.
The proposed changes to the residue limits in Australia are deeply troubling to Pesticide Action Australia, a non-profit lobbying to reduce the nation’s use of pesticides.
Executive director Josh Davis called on regulators to apply the brakes to allow independent scientists more time to scrutinise the chemical’s safety and establish a comprehensive body of independent, peer-reviewed evidence.
“Once again Australians are being exposed to a new chemical the full consequences of which may take decades to reveal,” Davis said.
“By then, multiple generations will have been affected.”
The APVMA spokeswoman said before isocycloseram was approved for use, the manufacturer submitted an extensive, high-quality package of toxicity data that met international standards.
The APVMA’s scientists, some of whom hold positions with eminent global bodies including the OECD (Organisation for Economic Co-operation and Development), then carried out a scientific assessment of the toxicity data.
“Based on the intended uses in accordance with the strict directions on the label, the APVMA was satisfied that the product would not be harmful to people, animals or the environment,” the spokeswoman said.
But Davis argued regulators should not rely so heavily on industry-sponsored studies.
“There is a huge conflict of interest in our opinion,” he said.
Australia has approved isocycloseram for spraying on an array of vegetables and fruits, including broccoli, cauliflower, corn and garlic.
Its manufacturer, global agrochemical giant Syngenta, has recently been at the centre of a storm of controversy over another one of its products, Paraquat.
The OECD, along with Europe and Australia’s environment departments, classifies isocycloseram as a type of per-and polyfluoroalkyl substance (PFAS), a family of compounds dubbed “forever chemicals” because they do not easily break down in the environment.
However, isocycloseram is not treated as a forever chemical when used on Australian farms because the APVMA adopted the US EPA’s narrower definition.
The APVMA is now moving to loosen restrictions over how much of the pesticide can remain on berries sold to consumers by lifting the maximum residue limits (MRLs).
The changes would allow a 500-fold increase in traces of isocycloseram on raspberries and blackberries, a 300-fold jump for blueberries and currants, and a 70-fold increase for strawberries and cranberries.
Public consultation over the changes finishes on Tuesday.
Once a niche food, berries have exploded in popularity, with around three-quarters of Australian households now purchasing them. The value of Australia’s annual berry crop surged to $1.3 billion in 2024.
Davis argued that forever chemicals shouldn’t be sprayed onto berries eaten by children at all, especially given berries were marketed as a health food and the pesticide residues could not be washed off at the sink.
“It’s a risk to this generation and ...will persist in our soil, water and wildlife for generations to come.”
The APVMA defended its pesticide limits, which were set using current berry consumption data, internationally recognised methods and verified by Food Standards Australia New Zealand.
Regulators establish an “acceptable daily intake”, which estimates the safe amount of a chemical that can be ingested daily over a lifetime.
The APVMA spokeswoman said limits for pesticide residues on berries were set “far, far below these health limits”.
Real-world exposure was hundreds or thousands of times lower than the “worst-case scenarios” used in safety assessments, she said.
Such assessments assumed a person was consuming all 39 foods that might contain isocycloseram every day of their lives and each of those foods was treated with the chemical. A further safety buffer of 100 times was also applied from where any health effect was expected to occur.
Isocycloseram is toxic to bees and other pollinators, which produce one out of every three bites of food we eat.
The pesticide can break down into trifluoroacetic acid, a forever chemical scientists warn is increasing exponentially in human blood and drinking water that was recently classified as toxic to reproduction by the European Chemicals Agency.
The APVMA said the agency’s assessments had factored in the accumulation of pesticide residues in soil and had developed restrictions on the product label to mitigate the risks of runoff.
“Other studies demonstrated no adverse effects on bees or their colonies when used in accordance with the directions,” the spokeswoman said.
But the potential for more PFAS to enter the environment was alarming to NSW Greens MLC Cate Faehrmann.
“There isn’t a more stark example of how broken our system is for regulating pesticides,” Faehrmann said.
“How can APVMA be entertaining the idea of approving another toxic PFAS chemical, while the federal government launches a class action against 3M for the devastating impacts its toxic PFAS firefighting foam has had.”