Insights into spatiotemporal distributions of trace elements in kelp (Saccharina japonica) and seawater of the western Yellow Sea, northern China

China is the largest kelp (Saccharina japonica) producing country in the world. Kelp consumption is a tradition in many Asian countries. However, S. japonica accumulates trace elements that exhibit potential health risks upon ingestion. Here, we selected six sampling sites, from the shelf to offshore waters, in a maricultural area of Ailian Bay in Rongcheng City, northern China and investigated the spatiotemporal distributions of trace elements in kelp and seawater from 2016 to 2018. We then evaluated the bioremediation potential and food safety of S. japonica. Most trace elements in S. japonica and seawater demonstrated no marked spatial variations. The trace element concentrations in the tested kelp did not exceed the food safety standards, indicating that it is safe for human consumption. Moreover, S. japonica has a high bioremediation capability for trace elements, and the kelp in the coastal waters of Rongcheng (with annual yield of 1.7 x 10(4) t DW) removed 28.60 kg Cr, 165.51 kg Cu, 682.54 kg Zn, 34.00 kg Cd, 52.53 kg Pb, 3.60 kg Hg, and 1305.53 kg As from the seawater per year. Our results will be useful for evaluating the bioremediation potential of S. japonica and for food safety management. (c) 2021 Elsevier B.V. All rights reserved.