Eating a Sunday roast can result in swallowing 230,000 particles of microplastics, a study has warned.
Microplastics are tiny pieces of plastic less than 5mm in size, which scientists believe can harm wildlife – and may pose health risks to humans.
Researchers said that eating a Sunday roast every day would be the equivalent to eating two plastic bags every year.
The study, conducted by University of Portsmouth scientists in partnership with Good Morning Britain, found that a chicken roast dinner made with plastic packaging contained seven times more microplastics than it would without.
The research suggests that plastic packaging is a major route for microplastics to get into human bodies.
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Dr Fay Couceiro, reader in environmental pollution at the University of Portsmouth, said: "From the results it would appear that the majority of microplastics in our food come from the plastic packaging it is wrapped in. However, there are other ways that plastic can enter the food chain.
"It could be getting into the vegetables through the soil or into our meat through grazing. Air has lots of microplastics in it too, so they could be falling on top of the food and finally it could be from the cooking utensils used when preparing a meal.
"Usually food samples are analysed for microplastics in their raw state under laboratory conditions. This allows us to understand how much plastic is inside a particular type of food.
"This study differs because we chose to look at what was actually on your plate after the food had been cooked.
"Instead of a sterile laboratory, the food was cooked in a normal kitchen, so it is likely the microplastics will come from a combination of the food, the packaging, cooking utensils and the air."
Alberto Costa MP, chair of the All-Party Parliamentary Group on microplastics, said: "Plastic can enter our bodies through the air we breathe and through our food as highlighted in this investigation.
"We don't yet know the effect this has on our health, but I would very much welcome more research and investigation into this so we can understand if there are any impacts."
Earlier this year, a study suggested that tiny particles of microplastic are already polluting every lake and river in Britain, posing as-yet-unknown risks to wildlife.
Even remote bodies of water such as Loch Lomond are polluted with plastic particles.
Researchers from Bangor University and Friends of the Earth collected water samples from rivers, reservoirs and lochs in England, Scotland and Wales.
Every sample contained plastic, with the River Tame in Greater Manchester having more than 1,000 particles per litre, and Loch Lomond having 2.4 particles per litre.
Ullswater in the Lake District had 29.5 shards of microplastic per litre.