Emerging contaminants (ECs) are biological and chemical pollutants that are not often identified in the ecosystem but pose a significant hazard to both humans and the environment. The aim of this study is to investigate the distinct classes of ECs from both anthropogenic and natural sources that are infiltrating aquatic systems universally. Additionally, we classified the ECs in a broad range. This chapter deciphers several anthropogenic origins such as industrial wastes, agricultural runoff (pesticides, herbicides, and fertilizers), urban sewage (untreated wastewater contains pharmaceuticals, microplastics (MPs), and harmful microbes), plastic pollution, household chemicals (detergents, personal care products (PCPs), and cleaning agents), and vehicle emissions. Potential difficulties of EC monitoring and control within a variety of aquatic ecosystems are discussed, thereby entailing the call for better surveillance and the development of more advanced wastewater treatment systems in an effort to mitigate the risks of uncontrolled drainage from wastewater treatment and discharge of ECs to water features. In conclusion, this chapter provides better insight into controlling ECs and provides a pollutant-free environment. The targeted audience of this chapter is environmental scientists, policymakers, chemical fertilizers, and the pharmaceutical industry.