A review on the distribution of persistent organic pollutants and their influencing factors along the nearshore of the East China Sea
The present study collected and analyzed the published data in recent decade on the distribution and influencing factors of six typical persistent organic pollutants(POPs)in the nearshore seawater and sediments of the East China Sea,including perfluoroalkyl substances(PFASs),polychlorinated biphenyls(PCBs),polybrominated biphenyl ethers(PBDEs),organochlorine pesticides(OCPs),phthalates(PAEs),and polycyclic aromatic hydrocarbons(PAHs).Based on the median effect concentrations and marine sediment quality criteria on ecological risk assessments of POPs in seawater and sediments,it was observed that the ecological risks of PCBs,PBDEs and OCPs at most of the nearshore sites of the East China Sea were low,but their concentrations reached slight to moderate risk level near Hangzhou Bay.PAHs concentrations were at moderate to low or lower risk levels,while PAEs concentrations were at moderate to high risk level.The concentrations of PFASs were generally at moderate or lower risk level,except for PFOS which exhibited relatively higher risk level near the Yangtze estuary.The distribution of terrestrial-derived POPs in the nearshore seawater and sediments was mainly controlled by the impacts of the Yangtze River diluted water,atmospheric wet and dry deposition,coastal currents,and tidal action.The concentrations of most tested POPs were relatively higher near the Yangtze estuary and Hangzhou Bay,and showing a decreasing trend towards the open sea and the southern coast.Within the muddy area along the coast of Zhejiang and Fujian and the East China Sea shelf,some of the tested POPs were remarkably higher in sediments,which highly related with the strong binding affinity of POPs on fine particles.The"Marginal filter effect"driven by the temperature and salinity gradients during the mixing of fresh water derived from Yangtze River and seawater in the East China Sea,resulting in higher POPs concentrations in the surface sediments at regions where salinity ranges between Ito 5.The seasonal hypoxia in the East China Sea promotes the reductive degradation of POPs,such as DDTs and PCBs.In addition to biodegradation,the distribution of POPs in the East China Sea was also affected by biopumping and bioturbation processes.Although China has strengthened the management and control of POPs,the coastal East China Sea is still facing their associated ecological risks,which requires future efforts on the improving the monitoring methods and risk evaluation standards of POPs,and further strengthen researches on the monitoring and environmental behaviors of emerging contaminants.
East China SeaYangtze estuarypersistent organic pollutantsspatiotemporal distributionrisk assessment
万方数据
维普
