Microplastics in Edible Salts and their Removal Strategy

Authors

Naveenkumar A. Yaranal
Dept. of Chemical Engineering, Indian Institute of Technology Guwahati, Guwahati, India
S. Senthilmurugan
Dept. of Chemical Engineering, Indian Institute of Technology Guwahati, Guwahati, India
Kaustubha Mohanty
Dept. of Chemical Engineering, Indian Institute of Technology Guwahati, Guwahati, India

Synopsis

As emerging contaminants, microplastics have attracted attention around the world. The poor degradability allows the plastic waste to stay in the water for a long time and it breaks into smaller and smaller pieces of plastic over time. The findings indicate that human ingestion of microplastics through sea salt is closely linked to the contamination of plastic particles in seawater. Microplastics present in salt may create a potential health hazard for humans. In this work, we have developed an innovative approach for the removal of microplastics from synthetic seawater with the help of membrane technology, which has the potential to avoid the transfer of microplastic particles into salts. The visual evaluation was performed using optical and fluorescence microscopy to classify the shape, size, number, and colour of microplastic particles. A wide range of MPs were found: 1400 - 1900 particles/kg in refined sea salt, 1900 - 2300/kg in unrefined sea salts. The composition of the microplastics were analysed by Raman spectroscopy. The most common MPs were polyethylene (PE), polypropylene (PP), polyethylene terephthalate (PET), nylon, and polystyrene (PS). This is the first study, to the best of our knowledge, where we successfully removed microplastics from seawater, which can be used further in the large-scale industry.

pollution21
Published
October 25, 2021