Microplastic contamination in water sediment and freshwater mollusc in Mae Kha Canal at Chiang Mai Province

Abstract

In present days, plastic waste is one of the most important problems in the world. In particular, non-reusable plastics can lead to the accumulation of plastic waste in the environment. Due to several causes, macroplastics are broken up into smaller pieces, called microplastics. These microplastics could contaminate ecosystem, food chains and be harmful to human health. This study aims to investigate the contamination of microplastic in water, sediment and freshwater molluscs in Mae Kha Canal, Chiang Mai province. Samples were collected at three sampling sites, including Pa-ton-ngam, Uun-ar-rii villag, and Baan-sob-kha communities. The results from this study show that there were 93 microparticles resembling microplastics. Microparticles were mostly found in freshwater molluscs (39 pieces [41.94%], with the average of 0.87 ±0.64 pcs/molluscs), followed by in sediment (37 pcs [39.78%], with the average of 1.37 ±0.63 pcs/kg dw.) and in water (17 pcs [18.28%], with the average of 3.71±4.80 pcs/L), respectively. Microparticles with size ranging from 200-500 µm were mostly found (34 pcs [36.56%]). The most common morphology and color of microplastics was fragments (51.61%) and bluish color (36.56%). Moreover, by using Fourier Transform Infrared Spectroscopy (FT-IR) technique to analyze microparticles shows that 60 % of random sampling of microparticles were microplastics with the most commonly found were polyethylene, polypropylene, polypropylene carbonate and polybutene, respectively.