This introductory course provides participants with a strong foundation of aquatic toxicology and how these concepts are applied to managing pollutants in aquatic environments. The course covers terminology, common test designs, and endpoints such as lethality and endocrine disruption. Important legacy and emerging pollutants of concern such as heavy metals, organic pesticides, PAHs, PCBs, PBDEs, pharmaceuticals, personal care products, and nanoparticles will also be presented. Fate and transport as it relates to bioavailability and pollutant partitioning in aquatic environments will be discussed. Water Quality criteria from the Clean Water Act with an emphasis on, and examples of, site specific criteria for metals using hardness correction, water effects ratio (WER), and the biotic ligand model (BLM) are also included.