Significance of the great protection of the Yangtze River: Riverine input contributes primarily to the presence of PAHs and HMs in its estuary and the adjacent sea

• Published in: Marine pollution bulletin Vol. 186; p. 114366
• Main Authors: Wang, Qian, Xu, Hanwen, Yin, Jie, Du, Shengnan, Liu, Caicai, Li, Juan-ying
• Format: Journal Article
• Language: English
• Published: England Elsevier Ltd 01.01.2023
• Subjects: China; Environmental Monitoring; Environmental Pollutants; Estuaries; Geologic Sediments; Heavy metals; Mercury; Metals, Heavy - analysis; PAHs; Polycyclic Aromatic Hydrocarbons - analysis; Rivers; The Yangtze River estuary; The Yangtze River protection; Water Pollutants, Chemical - analysis; China; The Yangtze River protection; PAHs; The Yangtze River estuary; Heavy metals
• ISSN: 0025-326X; 1879-3363
• DOI: 10.1016/j.marpolbul.2022.114366

The Yangtze River protection strategies are expected to improve the water quality and ecological function of the Yangtze River Estuary (YRE). The concentrations of 16 polycyclic aromatic hydrocarbons (PAHs) and 6 heavy metals (HMs) in the YRE were measured and the riverine fluxes were calculated subsequently. In particular, the concentrations of low molecular weight PAHs (LMW-PAHs), arsenic (As) and mercury (Hg) in seawater decreased over time, while those of other studied pollutants did not change a lot. In sediments, the concentration changes for all the pollutants were insignificant. For the present pollutants, the river input is the dominant source, and the flux decreased after the protection. The contribution of the discharge from wastewater treatment plants (WWTPs) was quantified. Its influence cannot be ignored. The seafood quality remained stable and the risk via diet was insignificant. Long-term monitoring is necessary, and the positive impact of the Protection Strategy is gradually emerging. [Display omitted] •The Yangtze River carried considerable PAHs and heavy metals into the estuary.•The protection strategies reduced the load from the river to its estuary.•The input from WWTPs and surface runoff could not be ignored.•The dietary risk of the seafood was acceptable.