Following our article on the ban of microbeads in cosmetic products in January 2018, it was announced on 15th March that a study carried out by Scientists based at the State University of New York in Fredonia discovered an alarming amount of plastic particles in bottled water. They “found roughly twice as many plastic particles within bottled water” compared with their previous study of tap water.

As a result The World Health Organisation (WHO) has announced a review into the potential risks of plastic in drinking water after a new analysis of some of the world’s most popular bottled water brands found that more than 90% contained tiny pieces of plastic.

How was the test carried out?

In the largest investigation of its kind, 259 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.

Orb’s findings suggest that a person who drinks a litre of bottled water a day might be consuming tens of thousands of microplastic particles each year.

The screening for plastic involved adding a dye called Nile Red to each bottle, a technique recently developed by British scientists for the rapid detection of plastic in seawater.

Previous studies have established how the dye sticks to free-floating pieces of plastic and makes them fluoresce under certain wavelengths of light.

Prof Mason and her colleagues filtered their dyed samples and then counted every piece larger than 100 microns – roughly the diameter of a human hair.

Particles smaller than 100 microns – and down to a size of 6.5 microns – were much more numerous (an average of 314 per litre) and were counted using a technique developed in astronomy for totalling the number of stars in the night sky.

In one bottle of Nestlé Pure Life, concentrations were as high as 10,000 plastic pieces per litre of water. Of the 259 bottles tested, only 17 were free of plastics, according to the study.

What is the consequence of plastics in bottled water?

The issue is that the long term effects of the microplastic particles is not yet known.

The brands who's water was tested pointed out that there is an absence of any regulations on microplastics and a lack of standardised methods of testing for them.

Currently, there is no evidence that ingesting very small pieces of plastic (microplastics) can cause harm, but understanding the potential implications is an active area of science.

Bruce Gordon, from the WHO, told the BBC: "When we think about the composition of the plastic, whether there might be toxins in it, to what extent they might carry harmful constituents, what actually the particles might do in the body – there's just not the research there to tell us.

"We normally have a 'safe' limit but to have a safe limit, to define that, we need to understand if these things are dangerous, and if they occur in water at concentrations that are dangerous."

Around 480bn plastic bottles were sold globally in 2016 - that’s a million bottles per minute or 20,000 per second.