A study from 2023 in the Royal Society of Chemistry “Characterization of microplastics in water bottled in different packaging by Raman spectroscopy” Bambino, et al.
This study used a sample of 130 different water bottles made of different material (70for PTET, 70 for rPET and 60 for glass). The study found “Overall, our results highlighted a low concentration of MPs (micro plastics) in all samples, with a mean of 5.08 ± 3.28 p L−1 for PET bottles, 3.21 ± 1.34 p L−1 for rPET and 8.65 ± 5.39 p L−1 for glass bottles. (p L-1 means one picogram (trillions of a gram) in one liter.)
In general, investigations which used different techniques, such as Fourier-transform infra-red spectroscopy (FTIR) and scanning electron microscopy/energy dispersive X-ray spectrometry (SEM/EDS), found a lower concentration of MPs in bottled water than Raman spectroscopy, mainly for smaller particles. In addition, our study showed that glass bottles contained more MPs than Pet and rPET bottles. This finding is in line with those of Oßmann et al.28 and Schymanski et al.29, who, using Raman spectroscopy, also found more MPs in glass bottles than in plastic ones. Another recent survey,35 performed by laser direct infrared spectroscopy (LDIR), confirmed this result, showing a greater content of MPs in glass-bottled water.
In our study, the spectral analysis highlighted the meaningful role of bottle caps in MP contamination of glass bottles. With respect to MP size, we found that the most representative particles in the analyzed water ranged from 20 to 100 μm, while smaller particles were more abundant in glass bottles than in the other packaging. (μm, stands for micrometer i.e. on millionth of a meter). Note: smaller particles are considered more harmful to humans.
In regards to human micro plastic exposure it should be noted that tires and synthetic textiles (clothing) are the largest sources of primary microplastics, contributing significantly to human exposure via air, water, and food. Vehicle tire wear accounts for up to 45% of microplastics in aquatic/terrestrial systems, while synthetic clothing releases millions of microfibers during laundering and wear. Tire Wear: As vehicles drive, the friction between tires and roads creates tiny particles, making tires a major, often underestimated source. These particles, which are about 1/4 plastic, are washed into waterways or become airborne. Synthetic Textiles/Clothing: Materials like polyester, nylon, and acrylic shed microfibers during washing, drying, and normal wear. A single 13lb load of laundry can release up to 18 million microfibers.
