Work

Synergistic interplay of weathered microplastics: Coupling sorption-leaching behavior and environmental risk implications

Year: 2025

Type: article

Abstract: This study investigated the effects of photo-weathering on microplastics (MPs) focusing on changes in their physicochemical properties, pollutant adsorption behavior, additive leaching characteristics, and associated human health risks. Polystyrene (PS) and polyvinyl chloride (PVC) MPs were exposure to UVC and Xenon light to simulate photo-weathering. Surface analyses revealed that UVC irradiation caused more significant changes in surface oxidation and hydrophilicity compared to Xenon exposure, with carbonyl index (CI) increasing at rates of 0.002/h and 0.001/h for PS and PVC, respectively under UVC irradiation. The O/C ratio reached 0.0978 for PS and plateaued at higher values for PVC under UVC exposure, while contact angles decreased for both MPs. Contrary to conventional understanding, weathering did not significantly impact heavy metal (As, Cu, Pb, Zn) adsorption onto MPs; instead, adsorption capacity varied primarily based on metal species and MP type. Photo-weathering significantly accelerated the leaching of di(2-ethylhexyl) phthalate (DEHP) from PVC, with the leaching rate constant being approximately 5 times faster for weathered MPs exposed for 600 hours compared to virgin. Probabilistic human health risk assessment using Monte Carlo Simulation showed the while both hazard quotient (HQ) and excess cancer risk (ECR) remained below regulatory thresholds, weathered MPs exhibited twice the risk values compared to virgin MPs. Thus, the role of weathered MPs as carriers of heavy metals and increased risks due to leaching of hazardous materials highlights the need for more in-depth and systematic investigation of various weathered MPs.

Source: Journal of Hazardous Materials Advances

DOI: 10.1016/j.hazadv.2025.100712

Authors: Saerom Park, Sang-Gyu Yoon, Jin-Yong Lee, Jinsung An

Institutions: Korea Institute of Civil Engineering and Building Technology, Korea University of Science and Technology, Hanyang University, Kangwon National University

Language: English

Topic: Microplastics and Plastic Pollution

Subfield: Pollution

Field: Environmental Science

Domain: Physical Sciences

SDG: Climate action

Open Access status: gold

Estimated APC paid: $1,400