Sources, impacts and solutions for plastics in South East Asia coastal environments

South East Asia is facing one of the most important marine plastic pollution crises on the planet, with a high level of global public concern about the impacts of this pollution on the health of its marine environment. Plastics are potential vectors for pathogens, metals and organic pollutants that could translate into health issues for society and ecosystems. Our project aims (i) to quantify the combined toxicity effects of organic chemicals and metals that are adsorbed to marine microplastics, which can produce a ‘combined’ pollutant with synergistic toxic effects, and (ii) to better understand how marine plastic particles could vector pathogens of humans, corals and fish. Our project will determine the effects of microplastics on microorganisms in coastal waters of SE Asia (Singapore, Malaysia, Indonesia, and Thailand). Microorganisms are at the base of the food chain, they are critical to life on our planet, key players of geochemical cycles, and at the heart of bioremediation processes. Singapore’s hydrodynamic connectivity to riverine sources in the Java Sea, the South China Sea and the Strait of Malacca make it the perfect location to study how microplastics, of different polymer types, properties and sources, affect microorganisms and impinge on species interactions. Our team will conduct a comprehensive investigation of the impact of microplastic particles on microorganisms sampled from different regions in SE Asia, spanning a range of different physical and chemical water typologies. Using cutting-edge analyses, including label-free acoustic sorting, metagenomics/metaproteomics, biogeochemistry and modelling, we will accurately assess the impact of microplastic pollution on microbial ecology dynamics and identify optimal conditions that promote microbially-induced biodegradation. Our project will combine for the first time innovative acoustic tweezing technology to sort different particles of microplastics according to their size, physical and mechanical properties with advanced comparative metaproteomics to assess the functioning of microbial communities. Furthermore, modelling will identify a network of sources and sinks across SE Asia and provide a temporal data on the risks associated with microplastics. This unique interdisciplinary approach will lead to vital advances in our understanding of the regulation of key microbial metabolism in polluted marine environments of SE Asia and lay the foundation for understanding localised conditions for the bioremediation of marine microplastics. Our project will deliver research-based solutions, impacting policy makers and identifying sustainable solutions for mitigating the detrimental effects on biodiversity. Our long term vision is that our results will benefit the overall economy in SE Asia by providing the necessary knowledge to reduce the volume of marine microplastic, which will ultimately lead to increased tourism and healthier aquaculture stocks and coral systems.