Microplastics are tiny particles measuring less than 5 millimeters. These can break down into even smaller fragments known as nanoplastics, which measure less than 1 micrometer and have the capability to penetrate human cells and tissues. While the presence of plastic particles has been confirmed in different human tissues, the exact impact on health is not yet clear. This is largely due to difficulties in detecting and analyzing such minuscule materials.
Researchers at Columbia University have made a significant breakthrough by enhancing a type of imaging technology, stimulated Raman scattering (SRS) microscopy. This method allows for the detection of microplastics and nanoplastics at an individual particle level without the need for labeling specific molecules.
Applying this refined technique in conjunction with machine learning algorithms, the team successfully identified seven prevalent types of plastics in bottled water samples. Notably, nanoplastics represented approximately 90% of the total plastic particles found. The research revealed that bottled water may contain plastic particle concentrations that are 10 to 100 times higher than previous estimates, which mainly accounted for larger microplastic particles. Among the detected plastics were polyamide and PET.
The enhanced SRS methodology can help improve our understanding of human exposure to nanoplastics. There are also plans to leverage this technology in the creation of filters aimed at reducing plastic pollution originating from laundry wastewater.