A new study utilizing advanced microscopy techniques has detected extremely high levels of micro and nanoplastic particles in several popular bottled water brands.
On average, each liter was found to contain over 200,000 plastic fragments – with around 90% sized in the nanoscale range below 1 micrometer. These pose heightened health risks compared to larger particles.
The miniscule synthetic polymer pieces likely originate from plastic bottle materials, purification filters, and other water treatment processes. But their sheer abundance and transmission potential raises pressing questions around the safety of packaged drinking water.
New Measurement Methodology
Previous assessments greatly underestimated nanoplastics abundance due to limitations of traditional analytical tools in identifying such minute particles smaller than a single bacteria.
To address such challenges, the researchers leveraged an advanced technique called stimulated Raman scattering microscopy recently co-invented by study coauthor Dr. Wei Min of Columbia University.
This provides unmatched precision and chemical specificity in detecting microplastics based on their distinct molecular structure – enabling the team to systematically scan bottled water samples.
Billions of Plastic Nanoparticles
Analysis of three top brands confirmed a jaw-dropping average of over 110,000 plastic nanoparticles per liter – that’s approximately three to ten times higher than prior maximum estimates.
The team successfully matched around 10% of these to seven common consumer plastic types, including PET and nylon. But the remaining 90% of identified particles were of unknown origin.
In total, some 8 billion nanoplastic pieces are present in average 73 liter residential bottled water consumption yearly – and the risks associated with ingesting such volumes are still poorly delineated.
Potential Exposure Pathways
While further research is still needed, initial studies show nanoplastics can rapidly enter the human bloodstream after being consumed compared to the larger microparticles confined to the gut.
The staggering amounts now measured in bottled water represent a likely exposure route. The high surface area of nanoplastics also enables chemical leaching and toxin absorption posing toxicological threats.
The HungryMicros study implicates plastic filtration membranes, bottle degradation, resin ion exchange systems, and coagulation aids as probable sources of contamination during purification and packaging.
Seeking Safer Alternatives
More concerningly, such purification-derived particles were found to outnumber even plasticizer chemical like PET leached from standard bottle materials under heat and pressure.
Consumers troubled by the prevalence of bottled water nanoplastics revealed in this study may reasonably consider safer alternatives until more decisive health guidance emerges. Tap water filtered at point of use represents an affordable option to avoid plastic while receiving key mineral nutrients.
Either way, the staggering new measurements highlight the pressing need to understand nanoplastics dissemination and biological impacts – especially among frequently consumed products.