Plastic danger hidden in rice

ONE of Australia’s most popular staple foods has been found to harbour “potentially dangerous” microplastics, a worldfirst Australian study has found.

University of Queensland researchers at the Queensland Alliance for Environmental Health Sciences identified 3-4mg of plastic in an average 100g serve of uncooked rice.

The study, published on Sunday in the Journal of Hazardous Materials, also found instant or pre-cooked rice contained four times more plastic – averaging 13mg per 100g serve.

Lead author Dr Jake O’Brien said they found washing rice before cooking reduced plastics contamination by 20 to 40 per cent.

Dr O’Brien said they used everyday rice bought from a local store. An average grain of rice was 8mm long, with microplastics defined as a plastic material measuring 5mm or less.

The researchers tested for seven different plastic types ranging from the most common plastic, Polyethylene to plastics used in clothing and food production, laminates, technical engineering, polystyrene, acrylics and tube piping.

The innovative method developed and used by the UQ research team is based on the plastic quantification technique used in their previous studies on plastics in seafood species and sewage sludge.

Dr O’Brien said the presence of microplastics was relatively low, but there was still much to be learned about their effects on human health.

“I don’t think people should be concerned, I think people should be aware,” he said.

“Currently there are many unknowns about how harmful consuming microplastics is to human health, but we do know exposure can cause an element of risk.”

He said it was still very early days in research to develop methods to measure plastic contamination in foods, and it was “challenging to determine our exposure and exposure sources of these chemicals”.

In 2019 Dr Thava Palanisami, from the University of Newcastle, co-led a project that combined data from more than 50 studies on the ingestion of microplastics by people.

The project led to a report that suggested people were consuming about 2000 tiny pieces of plastic every week. This was on average 5g – the size of a credit card.

Dr Palanisami said the presence of that quantity of microplastics in rice was a concern.

“Generally the smaller the size, the more potentially dangerous it can be to health,” he said. “It can get into the blood stream and the organs.”