Webinar title: Advancements and Reflections on Microplastics Research
Speaker: Eddy Y. Zeng
Webinar time: 15:00pm, November 24, 2023 (Friday)
Venue: Room 231, New Environmental Building; Tencent Meeting 783-967-686, Password 123265
Inviter: Ying Zhu, Jiayin Dai
Abstract:
In recent years, the issue of microplastics has become a hot topic in environmental research. The number of articles related to microplastics has been continuously increasing, with more than 1700 papers published in 2022. According to bibliometric analysis results, there has been a significant change in the hot words of main microplastics research from 2018-2020 to 2021-2023. For example, the focus shifted from 'surface water' to 'sediment' and from 'effect' to 'exposure' and 'mechanism'. This study will focus on the latest advances in the field of microplastics research over the last three years, including the biological exposure and microtoxicity of microplastics, as well as macroscopic long-range transport and migration. Microplastics were ingested by 85% of Alaskan cod in the Bering Sea, and more than one-third of the microplastics were in the size range of 100-500 μm, with a positive linear relationship between fish age and microplastic size. The amount of microplastics in the gut of wild seabirds was remarkably correlated with the diversity and composition of gut microorganisms, confirming the effect of microplastics ingested by seabirds on the gut microbiota of seabirds. In experiments exposing mice to nanoplastics, it was demonstrated that nanoplastics could be internalized in neurons through lattice protein-dependent endocytosis, causing mild lysosomal damage and slowing down the degradation of aggregated Parkinson's related α-synuclein. Microplastics, widely present in the environment, can undergo long-distance migration and transportation in both the atmosphere and water bodies. For example, atmospheric microplastics can freely transfer in the troposphere and even achieve intercontinental and transoceanic transport on a global scale. At present, there are many studies on global plastic river fluxes to the sea, and the predicted values of different models differ by up to five orders of magnitude. A top-down approach utilizing observed datasets of occean surface plastic concentrations and an ensemble of ocean transport models to reduce the uncertainty in global plastic emissions ultimately yields a best estimate of plastic emissions of about 0.7 (13~3.8) million tons/year. The floating amount in the ocean is much lower than the land emissions in global microplastic estimations, and the sediments in the Arctic Ocean may be one of the important sinks for marine microplastics missing from the global microplastic budget.
About the speaker:
Professor Yongping Zeng, School of Environment, Jinan University, received his B.S. degree in Geochemistry from University of Science and Technology of China in 1982, M.S. degree in Physical Chemistry from Sun Yat-sen University in 1985, and Ph.D. degree in Chemical Physics from the Department of Chemistry, University of Southern California, U.S.A. in 1992. Prof. Zeng returned to China in 2004, and once served as a researcher at the Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, and the Director of the State Key Laboratory of Organic Geochemistry (2006–2010). In 2003, he was granted by the CAS President’s International Fellowship for Distinguished Scientists (with excellent evaluation at the end of 2008); in 2005, he was awarded the Chinese National Science Foundation for Outstanding Scholarship (Foreigner); in 2008, he was awarded the Science Fund for Innovative Research Groups of the National Science Foundation of China as an academic leader, and in 2015, he was selected for the Fourth Batch of "Hundred Talents of Southern Guangdong" Program of Guangdong Province. Professor Zeng has been engaged in environmental geochemistry for a long time, and has made systematic innovations in the regional environmental processes of organic pollutants and human exposure risks. He has constructed a new type of passive sampling method system, which provides key technical support for systematic study of regional environmental transport of pollutants; clarified the mechanism of human activities on the evolution of organic pollutants in the offshore environment; created a model for estimating the global plastic flux into the sea by using the Human Development Index (HDI) as the main predictor for the first time, and corrected the bias of overestimation of the intensity of global plastic discharge in the rivers in China in particular; and finely assessed the organic pollutants in the water, and the risk of human exposure. In addition, he has also assessed the exposure of aquatic organisms and human beings to organic pollutants and the potential health risk of organic pollutants. Currently, he is the Editor-in-Chief of Environmental Pollution, a leading international environmental science journal.