A quarter nano million reasons to rethink bottled water
VIZAG: Bottled water is the safest way to remain hydrated, right? Now consider a recent study that quantifies the level of nanoplastics in each litre of branded bottled water. It's staggering - close to a quarter of a million pieces of microplastics on an average, according to a recent study published in the Proceedings of the National Academy of Sciences. Did the thought of safety just fly out of the window?
Plastic pollution is a global concern. Microplastic contaminations have been identified in various environments and even in human biological samples. The study indicates that the fragmentation of plastic polymers doesn't stop at the micron level but goes on to become nanoplastics at a mind-boggling magnitude.
The challenge in assessing nanoplastic concerns lies in the lack of effective analytical techniques. Traditional methods struggle with the label-free and heterogeneous nature of real nanoplastics in the environment. To address this knowledge gap, researchers developed a hyperspectral stimulated Raman scattering (SRS) imaging platform with an automated plastic identification algorithm. This innovative technique allowed for the analysis of micro-nano plastics at the single-particle level with high chemical specificity and throughput.
The study, which focused on bottled water as a model system, revealed humongous numbers. The concentration of micro-nano plastics was estimated to be around 2,40,000 micro-nano plastic particles per litre with 90% of them in the nanoplastic size range. It found the magnitude of microplastics levels was way higher than previously reported in bottled water. The research utilised high-throughput single-particle counting, uncovering extraordinary particle heterogeneity and nonorthogonality between plastic composition and morphologies.
The developed hyperspectral SRS microscopy proved to be a powerful platform for detecting nanoplastics, meeting the crucial requirements of sensitivity, specificity and throughput. The method utilised a narrowband SRS imaging scheme to detect nanoplastics as small as 100 nm. To overcome the sensitivity-specificity trade-off, a data-driven SRS-tailored spectral matching algorithm was introduced, based on a spectral library of common plastic standards.
The implications of this research extend beyond the laboratory, as the study examined three different bottled water brands, revealing a significant presence of micro-nano plastics. On an average, 78 to 103 plastic particles were identified in each field of view (FOV) for the three brands, significantly higher than blank samples. This suggests that people may ingest an estimated 2,40,000 plastic particles from each litre of bottled water.
While researchers don't yet have strong evidence on how nanoplastics affect human health, the study prompts a reflection on the consequences of a single-use lifestyle. “Plastics are now omnipresent in our daily lives. The existence of microplastics and possibly even nanoplastics has recently raised health concerns. In particular, nanoplastics are believed to be more toxic since their smaller size renders them much more amenable, compared to microplastics, to enter the human body,” the researchers explained.
The findings challenge the sustainability of current consumption habits, urging a re-evaluation of our reliance on disposable plastics. It makes us question the blindness of humans running behind a single-use lifestyle rather than following the concept of reuse.