Microplastics have been discovered in fruits and vegetables, with apples and carrots found to be the most contaminated, studies show.

Campaigners have called for an urgent investigation into the tiny pieces of plastic following the results of the research.

A study in the journal Environmental Research found microplastics had been absorbed into commonly eaten types of produce, with apples the most contaminated fruit and carrots the most contaminated vegetables.

The research highlighted “worrying” estimated daily intakes of plastic particles in adults and children, but they were lower in fruit and veg than from bottled water.

The findings led to researchers from universities in Italy and Tunisia demanding studies into the possible effects of microplastics on human health.

A separate piece of research in the journal Nature Sustainability found that microplastics can be absorbed by the roots of lettuce and wheat crops and transported to edible parts of the plant above ground.

Campaigners now want to know the health implications of microplastics – which are tiny pieces of plastic that can be formed when larger plastics degrade – in food.

Founder of Plastic Soup Foundation campaign group, Maria Westerbos, said: “For years we have known about plastic in crustaceans and fish, but this is the first time we have known about plastic getting into vegetables.

“If it is getting into vegetables, it is getting into everything that eats vegetables as well which means it is in our meat and dairy as well.

“What we need to find out now is what this is doing to us.”

Sian Sutherland, co-founder of environmental campaign group A Plastic Planet, said while it was known that plastics were in the air, oceans and soils, there is now proof it is also in fruit and vegetables.

She said: “But a five-a-day diet of toxic microplastics and chemicals is not what the doctor ordered. Today I’m calling for an urgent investigation into what these toxins are doing to our health.”