Are Vehicle Tires Major Contributors to Microplastic Emissions into the China Seas? A Simple Model Perspective.

Authors

Shuolin Xiao, Johns Hopkins University
Yuran Liang, Minzu University of China
Xiaowei Zhu, Portland State UniversityFollow
Simone Q. Kyes, Portland State University
Xiaofeng Cai, Beijing Normal University

Published In

The Science of the Total Environment

Document Type

Post-Print

Publication Date

2-19-2024

Subjects

Microplastics -- Environmental aspects

Abstract

Microplastics pose a substantial threat to our environment. Given China's large population and rapid economic growth, it is urgent to estimate the annual emissions of microplastics into its marine environment. The microplastics show a significant variation in their source emissions as well as in their physical and chemical properties, leading to differences in their transport and fate in aquatic environments. To account for these variations, we developed a process-oriented model that considers microplastics from different sources and the inter-provincial variation in their retention rate to assess annual microplastic emissions into the China seas. On a national scale, of the microplastics emitted, 36.05 % are from household laundry activities, 27.26 % are from the wear and tear of vehicle tires, and 24.04 % are from the abrasion of plastic household items. After emission, 60.21 % are removed by wastewater treatment plants. The overall proportion of microplastics that end up in the marine environment highly depends on the specific riverine retention rate of microplastics from vehicle tires. Including the high settling rate of these microplastics, this proportion drops from 9.96 % to 3.29 %, rendering vehicle tires a minor contributor to microplastic emissions into the China seas compared to other sources. Moreover, when using the density-dependent approach and considering the east/west dimension of each province, the microplastic emissions from vehicle tires into the China seas decrease from 71 % to 5.27 %. This underscores the urgent need for global and regional models to account for the detailed riverine transport process of microplastics from vehicle tires in order to enhance the accuracy of their emission estimates into coastal waters.

Rights

This is the accepted manuscript. The final version, © Elsevier B.V. All rights reserved, is available from the publisher: https://doi.org/10.1016/j.scitotenv.2024.171003

Locate the Document

https://doi.org/10.1016/j.scitotenv.2024.171003

DOI

10.1016/j.scitotenv.2024.171003

Persistent Identifier

https://archives.pdx.edu/ds/psu/41361

Citation Details

Xiao, S., Liang, Y., Zhu, X., Kyes, S., & Cai, X. (2024). [Post-print]. Are vehicle tires major contributors to microplastic emissions into the China seas? A simple model perspective. Science of The Total Environment, 920, 171003.