Microplastic pollution in Tolo region

Abstract

The ubiquitous nature of plastic wastes are now considered as a geological marker of Anthropocene era. Fragmentation and degradation of larger plastics debris generate microplastics with diameters less than 5 mm which has been circulating the world in all environmental matrices, including shorelines, surface waters, and even deep-sea sediments. Hong Kong is also subjected to this ubiquitous microplastic pollution problem. Previous studies have investigated the potential microplastic sources in Hong Kong and demonstrated that the western waters were heavily polluted by the riverine input from Pearl River. However, this study focused on investigating the potential sources of microplastic pollution in the Tolo region. Quantification and characterization of microplastics have been done at the strandline of four sandy beaches in the Tolo region. The concentration of microplastics ranged from 1.0 - 623.0 items/kg sediment. Nam Fung Wan was found to be the most polluted site with a median concentration of 623 items/kg. The features of the microplastics collected among sites were compared and the result demonstrated that there were significant differences in abundance, shapes, colors, and polymer compositions among sites. The findings suggested that the microplastic pollution in the Tolo Region is likely due to the local anthropogenic disturbance, including fishing activities, urban runoff, littering, and illegal dumping.