Aerosols Found Both in Wastewater Plants and Indoor Environments: NSYSU Hosts 2025 Aerosol Multidisciplinary Science International Forum

Aerosols are not only present in outdoor environments but can also be found in a wide range of indoor settings. The Aerosol Science Research Center (ASRC) of National Sun Yat-sen University (NSYSU), the only aerosol-focused research center in Asia, hosted the 2025 Aerosol Multidisciplinary Science International Forum. The forum brought together ASRC's cross-college, multidisciplinary faculty members to share their latest research, while also featuring distinguished invited speakers, including Professor Christian J. Kähler, aerosol expert from the University of the Bundeswehr Munich, Germany and Dr. Noor Zaitun Yahaya, President of the Asian Aerosol Research Assembly (AARA) and President of the Clean Air Society Forum for Malaysia (MyCAS), alongside many other external experts.

Professor Chia C. Wang, Director of the ASRC and Professor of Chemistry at NSYSU, noted that in recent years, public awareness of outdoor aerosols—especially fine particulate matter PM2.5 (particulate matter ≤ 2.5 micrometers), from both stationary and mobile emission sources—has significantly improved. However, many other potential sources of PM2.5, and even ultrafine particles such as PM0.1, in daily life are still often overlooked. Furthermore, aerosols from different sources vary in chemical composition and formation mechanisms, leading to diverse impacts on both the environment and human health.

Wang shared ASRC's latest findings using the only Single Particle Aerosol Mass Spectrometer (SP-AMS) available in Asia, revealing that the chemical composition of a single aerosol particle may simultaneously contain inorganic species such as heavy metal ions, as well as organic components such as polycyclic aromatic hydrocarbons (PAHs). This complex composition, beyond the limits of traditional analytical methods, demonstrates SP-AMS as a powerful tool for gaining deeper insights into aerosol chemistry. She also presented their recent findings of nanoscaled plastic particles identified in household aerosol samples, and bioaerosols detected in the air of wastewater treatment facilities. Professor Wei-Hsiang Chen, Director of the Institute of Environmental Engineering at NSYSU and an expert in wastewater risk assessment, further introduced new scientific insights into the mechanisms of antibiotic-resistant bioaerosols generated during urban and rural wastewater treatment processes.

Professor Christian J. Kähler from the University of the Bundeswehr Munich, Germany, presented his research on exhaled aerosols released by individuals of different ages and genders during both daily activities and intensive physical exercise. His talk also addressed the influence of indoor airflow on the efficiency of air purifiers in removing aerosol particles. Dr. Noor Zaitun Yahaya, President of the Asian Aerosol Research Assembly (AARA), shared how artificial intelligence can be applied in big-data analysis for air quality. Professor Yen-Ping Peng from the Institute of Environmental Engineering at NSYSU presented findings on the impact of ship exhaust emissions—both gaseous and particulate—on air quality in port areas. Associate Professor Yuan-Pin Chang from the Department of Chemistry at NSYSU shared his team's research utilizing aerosol optical tweezers techniques to study the multiphase chemical reaction mechanisms and interfacial properties of individual aerosol droplets. Invited external experts included Professor Pei-Shih Chen from the Department of Public Health, Kaohsiung Medical University, who discussed infectious bioaerosols, and Assistant Professor Wen-Hsi Cheng from National Kaohsiung University of Science and Technology, who presented his latest research on drone-based air sampling.

The 2025 Aerosol Multidisciplinary Science International Forum attracted participants from Taiwan, Germany, the United States, Malaysia, India, Vietnam, Pakistan, Turkey, and other countries. The forum featured diverse topics, ranging from aerosol sources, multiphase chemical reactions, and formation/transformation mechanisms, to the demonstration of nationally unique and regionally advanced aerosol detection techniques and cutting-edge research. The event also organized technical tours to ASRC's state-of-the-art aerosol research facilities and the air quality monitoring station established at the Port of Kaohsiung by Taiwan International Ports Corporation (TIPC).