Tests on major brands of bottled water have found that nearly all of them contained tiny particles of plastic.

In the largest investigation of its kind, 250 bottles bought in nine different countries were examined.

Research led by journalism organisation Orb Media discovered an average of 10 plastic particles per litre, each larger than the width of a human hair.

Companies whose brands were tested told the BBC that their bottling plants were operated to the highest standards.

The tests were conducted at the State University of New York in Fredonia.

Calculations have shown that 10 per cent of all plastic produced around the world ultimately ends up in the oceans. As a result, a large majority of global marine debris is in fact plastic waste. Human production of plastics is a well-known environmental concern, but few studies have studied the effects of tiny plastic particles, known as nanoplastic particles.

"Our study is the first to show that nanosized plastic particles can accumulate in fish brains," says Tommy Cedervall, a chemistry researcher at Lund University.

Exclusive: Tests show billions of people globally are drinking water contaminated by plastic particles, with 83% of samples found to be polluted

Microplastic contamination has been found in tap water in countries around the world, leading to calls from scientists for urgent research on the implications for health.

Scores of tap water samples from more than a dozen nations were analysed by scientists for an investigation by Orb Media, who shared the findings with the Guardian. Overall, 83% of the samples were contaminated with plastic fibres.

BWT, Europe's leading water technology company, has given Sahara Force India a brand-new look. In the 2017 Formula 1 season their VJM10 will be competing in the colours of pink, magenta and silver, clearly signalling a long-term relationship between BWT, the Austrian-headquartered water brand, and the Formula 1 team, Sahara Force India. The new colours were seen for the first time at the opening race of the season, the Australian Grand Prix, in Melbourne.

A check on the quality of tap water in Ho Chi Minh City by the Ministry of Health showed that the content of chlorine, widely used to purify water as a disinfectant and bleaching agent, fails to meet required standards.

Chlorine concentration was found exceeding the maximum level in areas near the reservoirs of Saigon Water Supply Corporation (SAWACO) and being below the minimum rate in other areas far from the lakes, according to the results of the check.