The identification and quantification of the widespread occurrence of trace organic chemicals at minute concentrations in the aqueous environment impacted by human activities is a result of rapid advances in environmental analytical chemistry. The body of knowledge regarding the characterization, fate and transport of these chemicals of emerging concern (CECs) in the natural water environment and engineered water treatment processes, as well as their toxicity, has grown substantially over the last two decades. Recently, the focus in the environmental chemistry community has shifted from these CEC parent compounds to the fate, transport, and toxicity of transformation products, which are generated through abiotic and biotic mechanisms in natural systems and during engineered advanced water treatment processes. This two-part book focuses on the studies and recent advancements towards the development of more harmonized strategies and workflows using non-target and suspects screening methods, including suitable bioassay approaches to assess the overall relevance of transformation products. Volume I covers the relevance of transformation products and international strategies to manage CECs, new methods for a comprehensive assessment of transformation products, and the fate and transport of transformation products in natural systems. This book is ideal for environmental scientists and engineers, particularly chemists, environmental engineers, public health officials, regulators, other chemistry-related professionals, and students.