Drinking from plastic bottles can raise blood pressure as a result of microplastics entering the bloodstream, a study suggests.

Microplastics have also been found in fluids in glass bottles, according to other research, and experts say the associated higher blood pressure can lead to an increased risk of heart disease.

The latest study found blood pressure went down after participants stopped all fluid intake, including water, from plastic and glass bottles, and drank only tap water for two weeks.

Researchers in the department of medicine at Danube Private University in Austra said: 'We concluded, after extensive research, that beverages packaged in plastic bottles should be avoided.

'Remarkable trends were observed. The results of the study suggest, for the first time, that a reduction in plastic use could potentially lower blood pressure, probably due to the reduced vol-ume of plastic particles in the bloodstream.

'The changes we observed in blood pressure suggest that reducing the intake of plastic particles could lower cardiovascular risk.'

Research shows that microplastics – microscopic fragments that are the result of plastic degradation triggered by UV radiation or the result of a bottle being knocked about – are ubiquitous.

Microplastics have been found in saliva, heart tissue, the liver, kidneys and placenta. Several studies have found high concentrations in water in plastic bottles.

In the new study, reported in the journal Microplastics, the researchers had eight men and women get their daily fluid intake from tap water and told them to abstain from drinks stored in plastic or glass bottles.

Several blood pressure measurements were taken at the start and during the study. The results showed a statistically significant decline in diastolic blood pressure – the pressure in the arteries when the heart rests between beats – after two weeks.