Cross-Shore Microplastic Accumulation on Sri Lanka’s West Coast One Year After the Catastrophic X-Press Pearl Pollution Event

Abstract

Understanding how marine debris accumulates within coastal ecosystems is a crucial aspect of predicting its long-term environmental and biological consequences. The release and subsequent dispersion of 50 billion microplastic pellets from the fire and subsequent sinking of the container ship X-Press Pearl along the western coast of Sri Lanka in 2021 provides an important case study. Here, we present a three-dimensional assessment of pellet accumulation (number density) along affected beaches and compare this with other common microplastic particles one year following the incident. Surveys confirmed that pellets were still widely present in the surface sediments of ocean beaches, with some locations returning average densities of 588 pellets m2 (very high according to the global Pellet Pollution Index [PPI]). Profiling deeper into beach sediments showed pellets were present to depths of 30 cm; however, most were restricted to the top 10 cm. Our observations of persistent pellet contamination of beaches along Sri Lanka’s west coast emphasize the need for continued monitoring of these types of events to assess the magnitude and persistence of risks to the environment, wildlife, and human well-being.