Biography

Professor Hyunook Kim
Department of Environmental Engineering, University of Seoul, Korea

Dr. Hyunook Kim is a Professor at Department of Environmental Engineering, University of Seoul, Korea, and the Director of Eco Water-Energy R&D Center, Korea. Professor Kim earned his B.S. degree in Environmental Science from Yonsei University, Korea in 1994, and an M.S. degree in Environmental Engineering from Johns Hopkins University in 1997, and a Ph.D. from University of Maryland at College Park in 2000. Before he joined the faculty at University of Seoul in 2002, he had worked as an Environmental Engineer for the US Department of Agriculture, MD, USA.

Professor Kim’s research in the area of water pollution control includes a number of projects on process control and operation of water and wastewater treatment plants. He has strong interest in the monitoring and control of contaminants of emerging concern. He has published more than 200 peer-reviewed journal papers and made more than 500 conference presentations. He has received a few awards, including the National Medal of Honor, for his academic and research achievements. He has served a few international journals as an Editor or an editorial board member. Currently, he is developing a new international standard for the management of microplastics in water and wastewater systems.

Abstract
Primary microplastics (MPs), which are man-made tiny plastic particles less than 5 mm in size, used to be added to various consumer products, including commercial laundry detergents and softeners. In particular, primary MPs were added to laundry detergents and softeners as exfoliating agents, emulsion stabilizers, or fragrance carriers. During the washing process, these MPs can be released into wastewater systems, eventually making their way into aquatic environments. Due to public concern about the potential health risk caused by MPs on the environment and human beings, a few countries (e.g., Korea, Taiwan, China, and the EU since 2017, 2018, 2021, and 2023, respectively) have banned the addition of any artificial MPs in laundry detergents and softeners.

In this study, we explore the sources and impacts of MPs in the commercially available laundry detergents and conditions; four laundry detergents and four softeners were purchased from a market. Since the analysis of MPs in the products is commonly performed using a μ-FT-IR spectrometer, which has a limited capability of identifying particles smaller than 4-50 μm, μ-Raman spectrometer has been used in this study. In short, 610-20000 MPs with the size of less than 50 μm were identified by the μ-Raman per 1-mL laundry detergent. However, only a few MPs could be detected when the μ-FT-IR based method was applied. Therefore, it was concluded that the μ-FT-IR based methodology to examine laundry products should be replaced by the one based on μ-Raman spectrometry.

Acknowledgement: This research was financially supported by the Graduate Program for Plastic-free Society funded by Korea Environmental Industry and Technology Institute (MOE).