Each week we swallow a credit card-worth of plastic particles. Here's what ... trends now
Would you like a side-order of plastic with your meal? The chances are it will come with one anyway.
The number of microscopic plastic particles that have found their way into our environment is so numerous that virtually any food that you choose to eat – fresh or frozen, precooked or raw - is likely to contain them.
But you won't spot them in your food – or feel them as you swallow.
These tiny particles are known as microplastics - sized from 5mm down to 0.0001mm, or nanoplastics, which are anything smaller than that.
Researchers are urgently trying to find ways to limit the amount of plastic absorbed into our bodies
Plastics break down throughout the environment and can enter the food chain through water, soil, feed and even the air
Each week we swallow about 5g of plastic particles, the weight of a credit card - according to a review of data from 50 studies, published in 2019 by scientists at the University of Newcastle in Australia.
Over a year this adds up to 260g, or half a pound.
Researchers are now urgently trying to find ways to limit the amount absorbed into our bodies (for steps you can take, see below) as science starts to uncover the consequences this contamination may be having for our health - and, apocalyptic as it might sound, for the future of mankind.
For just this week scientists have reported finding microplastics in men's testicles. Researchers, led by Professor Xiaozhong Yu at the University of New Mexico in the US, examined testes from human post-mortems as well from animals.
Professor Yu said: 'At the beginning, I doubted whether microplastics could penetrate the reproductive system. When I first received the results for dogs I was surprised. I was even more surprised when I received the results for humans.'
Researchers have suggested microplastics might help explain declining sperm counts in men.
While the full picture of the damage these particles may cause is yet to emerge, the evidence is mounting.
Last month, for example, a study by the same university, published in the journal Environmental Health Perspectives, found that the microplastics from our food can invade our bloodstream, liver, kidneys, even our brain.
A few weeks earlier the New England Journal of Medicine reported that having microplastics and nanoplastics in your arteries may significantly raise the risk of developing cardiovascular problems.
This was based on an analysis of patients with fatty deposits called plaques in their arteries - those whose plaques contained microscopic plastic particles were more than four times more likely than normal to have a heart attack or stroke in the ensuing three years.
Meanwhile in April neurosurgeons in China, writing in the journal Toxicology, warned that microplastics and nanoplastics can get past our brain's natural defence against infection – the 'blood-brain barrier', a normally formidable barrier that usually keeps dangerous substances from entering the brain – and disrupting vital functions such as the way our brain cells work.
The previous month another group of researchers in China reported that in lab studies on mice, the presence of microplastics in the brain appears to accelerate the progression of early dementia symptoms – called mild cognitive impairment – into full-blown Alzheimer's disease.
In all these studies the damage results from the microplastics sparking harmful levels of chronic inflammation in the body as our immune system tries to fight off these synthetic invaders.
Microplastics could have a longer-term impact on us all: in 2021 a study in the Journal of Hazardous Materials found that male mice fed microplastics subsequently became infertile – inflammation appeared to have affected the sperm-producing cells in the testes - and the report warned the same effect may be seen in humans.
'Unfortunately we can't avoid exposure to microplastics,' Nina Schrank, head of plastics at Greenpeace UK, told Good Health. This is because plastics break down throughout the environment, and thus can enter the food chain through water, soil, feed and even the air.
So what, if anything, can we do to protect ourselves against the plastic plague?
While the researchers behind last month's study in the journal Environmental Health Perspectives are looking at the impact on animals of a high-cholesterol/high-fat diet, or high-fibre diet (to see if diet affects the uptake of microplastics into our body), what can we do right now?
Fortunately, scientists are beginning to suggest some useful answers...
Wash your rice
Dr Jake O'Brien says: 'The levels of plastics found in pre-cooked or instant rice was four times higher than in uncooked rice'
Unlikely as it might sound, rice can be ridden with microplastics, according to a study by the University of Queensland.
Lead researcher and epidemiologist Dr Jake O'Brien warned in the Journal of Hazardous Materials that for every 100g (half a cup) serving of rice we eat, we consume on average 3mg-4mg of plastic. On average, this means we each may swallow around 1g per person annually via eating rice alone.
If we consume instant (i.e. pre-cooked) rice, this figure leaps considerably, his research found in 2021.
Dr O'Brien says: 'A significant result was the levels of plastics found in pre-cooked or instant rice, as it was four times higher than in uncooked rice, averaging 13mg per serving.'
Much of this is down to the way that rice is packaged and processed, during which time it comes into contact with myriad plastics that can rub onto the grains.
This, Dr O'Brien adds, means we can significantly reduce the microplastic content of rice simply by rinsing it thoroughly first.
'We found that washing rice before cooking reduced plastics contamination by up to 40 per cent,' he says.
Watch out for wine with plastic corks
Researchers found significant higher levels of microplastics in wine that had plastic corks on the bottles
Stick with old-fashioned corks if you want to avoid microplastics in your tipple, advised researchers in the journal Food Chemistry in 2020.
Corks went out of fashion because buyers feared that they tainted wine, leaving it 'corked'.
But researchers at the University of Aveiro in Portugal found that 24 of the 26 bottles of white wine with polyethylene stoppers they tested contained significantly high levels of microplastics, which the investigators said had migrated from the plastic corks.
Choose fresh food, rather than processedHighly processed protein products such as fish sticks, chicken nuggets, tofu and plant-based burgers contain significantly more microplastics than minimally processed products such as wild-caught fish and raw chicken breast, researchers reported in the journal Environmental Pollution in February.
Ecologists at the University of Toronto in Canada analysed more than a dozen different types of popular store-bought proteins including
