Study of Analysis Method on Microplastic Identification in Bottled Drinking Water

Abstract Microplastic has attracted the attention of the scientific community since the last 3 years due to its effects and damages to the environment. Microplastics are defined as tiny solid plastics generally ranging from 20 µm to 5 mm in diameter. They are roughly classified into small (20 µm–1 mm) and large (1–5 mm) microplastics. In this study two preparation methods to analyze the presence of microplastics in bottled drinking water are developed. Microplastic in drinking water is isolated by direct filtration and drying methods. By drying method, the isolated material is then analyzed using Fourier‐transform infrared (FTIR) spectroscopy, differential scanning calorimetry (DSC), and thermogravimetric analysis (TGA) instrument. Since the isolated material from filtration method is observed by digital microscope and further analyzed using FTIR microscope. FTIR microscope has been used to identify the type of plastic material. The small size of a particle starting at 20 microns can be identified using this instrument. Microplastics, high density polyethylene, and polyethylene terephthalate, size 20–200 µm are spiked in drinking water as control. The observation of the filtrates shows that microplastic only appeared in drinking water that has been spiked with microplastic. Further plastic identification using FTIR spectroscopy, DSC, and TGA needs microplastic in large amount.