Characteristics of Trace Metal Elements in Ambient Sub-Micron Particulate Matter in a Coastal Megacity of Northern China Influenced by Shipping Emissions from 2018 to 2022

• Published in: Atmosphere Vol. 15; no. 3; p. 264
• Main Authors: Du, Jinhua, Liu, Ziyang, Tao, Wenxin, Wang, Ting, Zhao, Jiaojiao, Gong, Weiwei, Li, Yue, Xue, Lian, Yang, Jianli, Wang, Chaolong, Zhang, Houyong, Wang, Fei, Sun, Yingjie, Zhang, Yisheng
• Format: Journal Article
• Language: English
• Published: Basel MDPI AG 01.03.2024
• Subjects: Air masses; Air pollution; Air quality; Autumn; Clean energy; Clean fuels; Climate and health; Climate change; Coasts; Composition; Distribution; Emission analysis; Emissions; Emissions control; Environmental aspects; Environmental monitoring; Environmental regulations; Fuel oils; Heavy metals; Humidity; Megacities; Micropollutants; nickel; Outdoor air quality; Particles; Particulate emissions; Particulate matter; PM1; Pollutants; Ports; Qingdao; Quality control; Regression models; ship emission; Shipping; Ships; Sulfur; Sulfur content; Sulfur dioxide; Sulphur; Suspended particulate matter; Trace elements; Trace elements (nutrients); Trace metals; Tracers; Urban areas; vanadium; Zinc; China; Beijing China; United States > US
• ISSN: 2073-4433; 2073-4433
• DOI: 10.3390/atmos15030264

Various shipping emission restrictions have recently been implemented locally and nationally, which might mitigate their impacts on regional air quality, climate change, and human health. In this study, the daily trace metal elements in PM1 were measured in a coastal megacity in Northern China, from autumn to winter from 2018 to 2022, spanning DECA 1.0 (domestic emission control area), DECA 2.0, IMO 2020, and Pre-OWG Beijing 2022 stages. The trace element changes of V, Ni, Pb, and Zn in PM1 were analyzed. The concentrations of V declined with shipping emission regulations implemented in 2018–2022 at 3.61 ± 3.01, 1.07 ± 1.04, 0.84 ± 0.62, and 0.68 ± 0.61 ng/m3, respectively, with the V/Ni ratio decreasing at 1.14 ± 0.79, 0.93 ± 1.24, 0.35 ± 0.24, and 0.22 ± 0.18. The V/Ni ratio was dominated by the shipping emissions in the DECA 1.0 stage but has been more affected by the inland sources since DECA 2.0. The V/Ni ratio of local transport air mass was higher than that of long-distance transportation, indicating that some ships were still using high-sulfur fuel oil, especially for the ships 12 nautical miles from the coastline. The multiple linear regression model showed a better fit using V as a tracer for ship emission sources of ambient SO2 in the DECA 1.0 stage, while the indication effect reduced since DECA 2.0. The V and V/Ni ratios should be carefully used as indicators of ship sources as more vessels will use clean fuels for energy, and the contribution of inland sources to V and Ni will gradually increase.