Pregnant women and breastfeeding mothers warned about eating Australian honey.

It’s a food often associated with health benefits – and often touted as a superfood but new research is cause for concern as to whether some degree of caution should be used in consuming honey.

Research published in the Food Additives and Contaminants scientific journal has revealed that Australian honeys are the most contaminated in the world with natural poisons linked to chronic disease including cancer of the liver and breast.

The concerning findings has prompted experts to warn that these honeys could be dangerous for pregnant and breast-feeding mothers and could lead to a higher risk of organ damage from such toxins for unborn babies and breast-fed babies.

All but five Australian honeys tested had more contaminants than the European Food Safety Authority would consider safe or tolerable.

The researchers found that nearly every Australian honey was contaminated.  Varieties such as Australian organic, floral blend, rainforest and blue borage had the highest levels of pyrrolizidine alkaloids.

Fairfax Media reports that under the Australian Food Code the use of poisonous weeds such as Paterson’s curse or Salvation Jane and Fireweed is banned in human food. The flowers on such plants are laced with chemicals called pyrrolizidine alkaloids that are considered the most common cause of poisoning in humans and livestock worldwide.

However with honey Food Standards Australia and New Zealand (FSANZ) allows it to be sourced from restricted plants, as long as it is blended with other honey to dilute it.

“Removing source plants is not feasible for many areas where apiaries are kept,” a FSANZ spokesperson told Fairfax Media. “Contaminants should be kept as low as achievable, therefore blending is the most practical way of reducing the levels of pyrrolizidine alkaloids.”

But other food authorities around the world see blending as an unfeasible solution.

The European Food Safety Authority, the UK Committee on Toxicology and the German Institute for Risk Assessment direct against the dilution of contaminated food.

An expert toxicologist Dr John Edgar said that dietary exposure to these poisons could be a significant cause of cancer.

“Reducing the contamination in foods such as honey, teas, salads, flour, dairy and herbal products could result in a significant reduction in cancer cases worldwide,” he told Fairfax Media.

The European Food Safety Authority considers a safe intake of pyrrolizidine alkaloids to be 0.0007 micrograms per kilogram of body weight, per day.

But Australian standards are more lax, recommend restricting intake to 1 microgram.

According to the NSW Department Primary Industries website Paterson’s Curse, while “toxic to livestock” and known to “affect human health” is also “valuable to the honey industry.”

The website says “ Paterson’s curse is also valuable to the honey industry. It flowers early in the apiarists’ productive season, providing both the large amount of pollen necessary to build up bee numbers in a short time and a high level of nectar, which provides an early flow of honey.”

The Australian Honeybee Industry Association has responded to the report saying that there is not one single case documented of human health being unfavorably affected as a consequence of the consumption of honey containing very low levels of alkaloids.

“Australian consumers of Australian honey have nothing to fear and they should continue to enjoy our great Australian honeys.”