Comparison of Microplastic abundance in varying depths of deep-sea sediments, Bay of Bengal

Globally, there is escalating evidence on the pervasion of microplastics (MPs) in marine ecosystems. However, knowledge of its distribution in outlying environments such as the deep sea is scarce. With this objective, sediment samples from the Krishna Godavari (KG) Basin, Bay of Bengal, were collected at varying depths of 225m, 230m, and 1070m, respectively. The highest concentration of microplastics was recorded at 230m (12 MPs/ 50 g DW) followed by 1070m (10 MPs/ 50 g DW) and 225m (2 MPs/ 50 g DW) respectively. MPs were categorized based on their shape, size, and colour. In shape distribution, filaments contributed about 67%, trailed by fragments (25%) and films (8%), respectively. Black (21%) was the dominant colour, followed by transparent (17%). More than half of the MPs (52%) lies within the 1-1000 µm size range. The surface morphology of the MPs was studied using Scanning Electron Microscopy. The polymer composition of the suspected MPs was characterized using Raman Spectroscopy.