Ecotoxicological evaluation and risks of emerging chemicals of concern in coastal regions of South China

The coastal environment of south China, particularly the Pearl River Delta (PRD) region, has been undergoing significant modifications due to rapid urbanization, economic growth and industrialization. These activities have increased the demand for new and existing chemicals used in the manufacture of products for both domestic use and export. It is, therefore, conceivable that large amounts of toxic substances, including classes of compounds referred to as “Emerging Chemicals of Concern (ECCs)”, have found their way into the coastal environment of the PRD. ECCs, such as halogenated flame retardants (HFRs), per-/polyfluoroalkyl substances (PFASs), pharmaceuticals and personal care products (PPCPs), and organic ultraviolet filters (UVFs), have been detected in coastal waters as well as sediments and aquatic biota. The presence of certain ECCs in local wildlife such as marine mammals and waterbirds indicates that some of them are bioavailable and are bioaccumulative. Recent studies carried out in the South China Sea further revealed high levels of some ECCs in seawater and sediment samples collected at the mouth of the Pearl River as well as the shelf of the PRD as compared with other coastal sites. Analyses of ECCs in blubber samples of local marine mammals collected over a ten-year period provided information on the temporal trends of some of these compounds in the marine environment. Although HFRs, PFASs, PPCPs, and UVFs have attracted much attention as global environmental contaminants, there are still considerable data gaps in our understanding of the environmental fate and risks of these contaminants in the PRD region. This paper aims to discuss the current status and trends of important ECCs in South China. Furthermore, the ecotoxicological impacts of chiral contaminants will also be discussed. Copyright © 2019 ICMPE-9.