U.S. researchers recently tested 259 bottled waters from 11 different brands across nine countries. Brands included Aquafina, Dasani, Evian, Nestle Pure Life and San Pellegrino. The researchers found that 93 percent of this bottled water showed some sign of microplastic contamination.
The researchers found an average of 10 microplastic particles per liter (MPP/L) that were >100 microns (about the width of a human hair.) They found an average of 325 MPP/L that were >6.5 microns (about the size of a human red blood cell).
This is twice as much microplastic as a previous study found in tap water. Some brands and bottles had thousands of MPP/L. One sample had more than 10,000 MPP/L.
“The data suggests that contamination is at least partially coming from the packaging and/or the bottling process itself,” the researchers say.
Are these microplastics dangerous? Health experts don’t really know. Certainly, the smaller particles (<100 microns) are most biologically relevant, as they could find their way into living organisms and accumulate in certain organs. As a result of these findings, the World Health Organization has announced a review into the potential risks of plastic in drinking water.
But there are several caveats to this study. First, the research (which was led by journalism organization Orb Media) has not been peer reviewed. Second, the smaller particles (6.5-100 microns) were identified using a Nile Red dye staining solution and an optical microscope. Though the lead scientist said the particles can be “rationally expected to be plastic,” their actual make-up could not be confirmed by this technique.
As a result, many bottled water manufacturers are questioning the findings.
Agilent has been working with leading academics to develop accurate methods for detecting and quantifying microplastics (>10 microns) in water, soil and other samples, using Fourier-Transformed Infrared technology. FTIR imaging reduces the risk of false positives and false negatives by individually matching each particle.
Sample preparation methods are optimized for different sample types. Further research has the potential to detect MPPs as small as 1 micron. This would allow biologically relevant MPPs to be fully characterized.
In April, Agilent will host a series of live webcasts on “Microplastics, from Beach to Bench: Complete Characterization and Chemical Identification Using Mobile FTIR and FTIR Imaging Technologies.” The speaker will be Prof. Jes Vollersten, professor of Environmental Engineering at Aalborg University, Denmark. You can register here.
“FTIR imaging has been shown to be an accurate, effective and robust technology for measurement of microplastics in the environment,” says Tarun Anumol, Agilent’s Global Environment marketing manager, “thus potentially being a good candidate to create standard methods with.”
For more information go to:
- Synthetic Polymer Contamination in Bottled Water (Orb Media) (PDF)
- How Big is a Micron? (Bacteria World)
- Plastic particles found in bottled water (BBC)
- WHO launches health review after microplastics found in 90% of bottled water (Guardian)
- Analysis of Microplastics using FTIR Imaging (Application Note) (PDF)
- Agilent Advanced FTIR Spectroscopy Instruments and Supplies
- Agilent Environmental Solutions
- Microplastics, from Beach to Bench: Complete Characterization and Chemical Identification Using Mobile FTIR and FTIR Imaging Technologies (Webinar)