Surface water assessment of microplastic contamination at three beaches in North Goa, India

Abstract

Microplastic (MP) contamination in aquatic environments poses a persistent and serious threat to ecosystem health, necessitating comprehensive investigations. This study examines MP pollution in the surface waters of the northern beaches of Goa, including Baga, Anjuna, and Vagator. Results revealed that all three beaches are contaminated with MPs, with an average abundance of 0.47 MP/L. Among them, Baga Beach exhibited the highest concentration (0.6 MP/L), followed by Anjuna (0.5 MP/L) and Vagator (0.3 MP/L). Fibres were the most dominant shape of MPs, while colourless (56.5 percent) and 0.3-1 mm (68.62 percent) MPs were prevalent across all beaches. Common polymers such as polyethylene terephthalate (PET), polyamide (PA), polypropylene (PP), polyethylene (PE), and polystyrene (PS) were identified in the water samples. Risk assessment indices, including the Pollution Load Index (PLI), Polymer Hazard Index (PHI), and Coefficient of Microplastic Impact (CMPI), highlighted varying levels of ecological risk. PLI values exceeding 1 indicated pollution at all beaches, while PHI categorized the risk at level V due to hazardous polymers like PA and PS. CMPI emphasized the extreme impact of fibres on coastal waters. Scanning Electron Microscopy (SEM) analysis revealed surface degradation and weathering of MPs, providing insights into their environmental fate. This study indicates the presence of MP contamination along the northern beaches of Goa, highlighting the need for continued monitoring and the implementation of preventive measures to mitigate potential environmental impacts. Furthermore, these findings provide a critical baseline for future research and contribute to the formulation of strategies to manage and mitigate plastic pollution in coastal environments.