The microplastics found in bottled mineral water are significantly higher than those present in tap water. This is revealed by an Orb Media study that analysed hundreds of samples — including one Italian brand.
More than 90 per cent of bottled mineral water contains microplastics. Researchers at the State University of New York in Fredonia analysed 259 bottles from 11 different brands, including the Italian brand San Pellegrino. Of these, only 17 were free of plastic. According to the study, commissioned by Orb Media, one litre of bottled water contains on average 10.2 plastic fibres the width of a human hair — tap water, by contrast, contains 4.45. The number of finer particles would be even higher: 314.6. One of the bottles analysed contained 10,000.
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The thicker fibres are made up of 54 per cent polypropylene, the material used for caps. 16 per cent is composed of nylon, 6 per cent of PET. Most are found in plastic bottles, but even glass ones are not immune to contamination. The researchers purchased them in shops or online, in 19 locations across the United States, China, Brazil, India, Indonesia, Mexico, Lebanon, Kenya and Thailand.
One of the methods used to identify microplastics in the water was the application of a dye called Nile red, capable of revealing their presence. This choice was criticised by Nestlé: the company believes the dye can generate "false positives" and independently analysed 6 of its own water bottles, demonstrating that they contained between 0 and 5 plastic fibres. Coca-Cola told the BBC that it uses very strict filtration methods, but is aware that since microplastics are now found everywhere, their presence cannot be ruled out even in highly processed products.
Another study revealed the presence of microplastics in the majority of bottles from 19 American brands. The United States is also the country where tap water was found to be most contaminated. Sherri Mason, who conducted the chemical analyses for Orb Media, said that "this is not about pointing the finger at any particular brand, but about showing how plastic is now everywhere, and has become such a widespread material that it can be found even in staple goods". Microplastics frequently end up on our tables because they are ingested by marine organisms.
Most people choose bottled water because they consider it safer, but that is not necessarily the case. "If tap water is of high quality, it is always the best choice," commented Scott Belcher, professor of toxicology at the University of North Carolina. A spokesperson for the World Health Organization told the British newspaper the Guardian that the matter will be examined more closely to understand what the consequences for human health are of ingesting plastic fibres: the greatest risks could come from the pollutants they release.
