Australia's biggest supermarkets are standing by Australian honey producers in the wake of international researchers claiming Australian honeys are the most contaminated in the world.
Woolworths and Metcash, which owns the IGA brand, haven't altered honey supply agreements, saying all the food, including honey, they stock complies with Food Standards Australia New Zealand guidelines.
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Find out about what's inside Australian honey that could be making us sick.
The food regulator and several Australian academics have also backed the quality of Australian honey, dismissing research published in the Food Additives and Contaminants scientific journal.
All but five Australian honeys tested had more contaminants than the European Food Safety Authority would consider safe or tolerable, according to the report.
A Food Standards Australia New Zealand spokeswoman said some types of honey contain "high levels of naturally occurring plant toxins known as pyrrolizidine alkaloids", but it was no cause for alarm and the levels should not make people sick.
"It's important to point out that for people who eat an average amount of honey, the levels of pyrrolizidine alkaloids [PA] should not be a cause for concern," the spokeswoman said.
"Although acute poisoning incidents have occurred in other countries from contamination of PA plants in wheat, salad and other crops there have been no reports of acute poisoning from honey, and no other reports of PA poisoning in Australia and New Zealand."
The toxins may get into honey when bees forage on the flowers of weeds such as Paterson's curse. The food standards spokeswoman said exclusive Paterson's curse honey was rare and the industry had clamped down on the spread of the weeds across the countryside.
If some bees had foraged in Paterson's curse flowers, she said processors blended their honeys to reduce the pyrrolizidine alkaloid content to a safe level.
A Woolworths spokesman said "we adhere to all Food Standards Australia New Zealand health guidelines when it comes to the sale of honey products in our stores."
A Metcash spokesman said it did the same, while Coles declined to comment.
Dr Shona Blair, of the University of Technology Sydney, who is a microbiologist and has studied the anti-microbial and healing properties of honey, said there was no evidence that consuming Australian honeys harmed people's health.
Even most European-produced honeys don't meet the current European guidelines for PA content.Dr Shona Blair
"In fact numerous other recent scientific studies have demonstrated likely health benefits associated with Australian honey," Dr Blair wrote online science news website Scimex.
"Far from being considered a carcinogen, honey is even sometimes used to help manage side-effects of cancer treatments."
Dr Blair said a report from the Rural Industries Research & Development Council, which will soon be published, will show Australian honey is some of the cleanest and purest in the world in terms of chemical contamination.
"The Australian and international standards for food PA content are currently under review by experts. It should be noted that …even most European-produced honeys don't meet the current European guidelines for PA content."
Dr Nadine Chapman, of the University of Sydney, said claims that Australian honey was the most contaminated in the world was an "exaggeration".
"Australia does not have the varroa mite and a number of other pests and diseases, we use less chemicals to manage our bees; we also try to minimise exposure to pesticides," Dr Chapman wrote on Scimex.
Professor Andrew Bartholomaeus, of the University of Canberra and University of Queensland, said people would be "wise" to avoid honey produced solely from Patterson's curse, which is not considered a commercial honey and is normally only available from speciality shops or farmers markets.
He said high levels of PA exposure has been linked to liver and other cancers in humans.
"Honey producers have previously been advised to blend such honey with that produced from other flowering plants to keep [PA] levels as low as possible. [So] there is unlikely to be a significant human health risk from consuming normal amounts of Australian honey," Professor Bartholomaeus said.
Ben McKee, the managing director of Australia's biggest honey processor, Capilano, said "best practice modern farming techniques" had slashed the amount of honey produced from Paterson's curse to "next to nothing" during the past decade.
"Farmers' actions to rid the country of this weed, such as less to no fallow rotation of crops, better use of more selective herbicides and the major success of biological control programs have significantly reduced the presence of Patterson's curse," Dr McKee said in a statement.
"No longer do we see fields of purple flowering weeds in Australia. This change in environment has resulted in an insignificant production of this type of honey in Australia and it is not considered a commercial honey that will be used in retail honey products."