Interaction of Emerging Contaminants with other Contaminants in Aquatic Matrices

Emerging contaminants (ECs) are becoming an increasing risk to fresh water ecosystems across the globe, but little is known about their interactions with other pollutants in the complex aquatic environment. In this chapter, the complex character of ECs, such as pharmaceuticals, personal care items, per- and polyfluoroalkyl substances (PFAS) and microplastics, is presented with references to their wide range of origin and entry into water systems. We explore the complex chemical, biological, and physical interactions between ECs and more traditional contaminants that can result in synergistic or antagonistic interactions, generate new transformation products, and modify mobility. These interactions have major environmental impacts on the health of ecosystems, the structure of food webs, and cumulative toxicity effects on aquatic organisms and human health via multiple exposure routes. We also discuss the analytical issues related to the detection and quantification of complex mixtures of ECs and discuss the sophisticated chromatographic and spectrometric methods, and ecotoxicological assessment methods. Lastly, the chapter discusses the existing remediation and management interventions, such as high-technology wastewater treatment systems and source reduction efforts, and makes policy prescriptions to reduce the risk of these complex mixtures of contaminants. Understanding these interactions will be important in developing effective monitoring, risk assessment, and remediation strategies to protect aquatic habitats and human health.