water Article Elemental Contaminants in Surface Sediments from Jiulong River Estuary, China: Pollution Level and Ecotoxicological Risk Assessment Philomina Onyedikachi Peter 1,2, Azhar Rashid 3,* , Liyuan Hou 1,4, François Nkinahamira 1,2 , Claude Kiki 1,2, Qian Sun 1, Chang-Ping Yu 1,5 and Anyi Hu 1,* 1 CAS Key Laboratory of Urban Pollutant Conversion of Urban Environment and Health, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China;
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[email protected] (C.-P.Y.) 2 University of Chinese Academy of Sciences, Beijing 100049, China 3 Nuclear Institute for Food and Agriculture (NIFA), G.T. Road, Tarnab, Peshawar 25000, Pakistan 4 Department of Chemistry, SUNY College of Environmental Science and Forestry Syracuse, Syracuse, NY 13210, USA 5 Graduate Institute of Environmental Engineering, National Taiwan University, Taipei 10617, Taiwan * Correspondence:
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[email protected] (A.H.); Tel.: +92-(0)334-5326024 (A.R.); +86-592-6190582 (A.H.) Received: 9 April 2020; Accepted: 3 June 2020; Published: 8 June 2020 Abstract: Estuaries, being the transitional zones between freshwater and marine environments, are important for protecting and rehabilitating the aquatic environments. Sediments from freshwater and marine environments were studied in Jiulong River Estuary (JRE) in different years for rare earth elements (REEs) and some environmentally important metal and metalloid elements (MMEs). 1 The concentration of REEs ranged from 0.11 (Tm) to 296.20 mg kg− (Ce), while that of MMEs 1 ranged from 0.40 (Cd) to 86,000 mg kg− (Al).