Your favorite brand of bottled water is likely contaminated with tiny plastic pieces. An average of 10.4 microplastic particles were found per litre of bottled water which was more than 100 μm (micrometre) in measurement.
"Microplastics have been reported in tap water, beer and many other foods, but I think that people will be surprised that nearly all bottled water appears to be contaminated too". As odd as it may sound, we simply don't definitively know what the dangers of long-term plastic ingestion on humans may be, which is why the caution around the ubiquity of microplastics is certainly nothing but sensible.
Using an infrared microscope, the researchers found that, for particles around 0.1 millimeters in size, there's roughly 10.4 per liter (2.3 gallons) of bottled water in various major brands.
Jacqueline Savitz, chief policy officer for North America at Oceana, a marine advocacy group that was not involved in the research, said the study provides more evidence that society must abandon the ubiquitous use of plastic water bottles.
Contacted to comment on the findings, the companies behind the brands have insisted that their products meet the highest standards for safety and quality.
Microbeads - tiny plastic beads found in some beauty products that were banned in the U.S.in 2015 - are another source of plastics in water.
Polypropylene was found to be the most common type of plastic fragment found, which is the same type of plastic used to make bottle caps.
Only 17 of the bottles surveyed (7%) had no contamination.
In order to test bottled water, a dye called Nile Red is infused into each bottle which then binds to the plastic.
The make-up of these particles was not confirmed but Prof Mason said they can "rationally expected to be plastic".
Stiv Wilson, campaign coordinator at Story of Stuff, said finding plastic contamination in bottled water was problematic "because people are paying a premium for these products".
Previous studies have established how the dye sticks to free-floating pieces of plastic and makes them fluoresce under certain wavelengths of light.
Researcher Abigail Barrows of Ocean Analytics, who carried out the research for Story of Stuff in her laboratory in ME, told The Guardian there were several possible routes for the plastics to be entering the bottles.
"What we do know is that some of these particles are big enough that, once ingested, they are probably excreted, but along the way they can release chemicals that cause known human health impacts", Mason told BBC News. Dr Andrew Mayes, a University of East Anglia scientist who developed the Nile red technique, told Orb Media he was "satisfied that it has been applied carefully and appropriately, in a way that I would have done it in my lab". The researchers believe that some of the microplastics came from the packaging or the packaging process. Tan reasoned that a thorough research on the effects of microplastic exposure is still limited, however, Tan referred to one of the research conducted by the United States' National Center for Biotechnology Information that studied effects of microplastic particles towards planktons in tainted oceans.