Environmental Chemistry and Toxicology is an emergent course in Ethiopia. It has great role in mitigating solution for different environmental stresses. All human activities irrespective of the scope and severeness have an impact in soil, air, water and life of the receiving bodies. Thus, the main focus of this book is to study the fate of chemical pollutants in the environment. This book comprises five chapters such as, Introduction to Environmental Chemistry, Aquatic Chemistry and Water pollution, Atmospheric Chemistry and Air pollution, Soil Chemistry and Pollution and Environmental Toxicity and Toxicology. The overall goal of this book is to gain an understanding of the fundamental chemical processes that are central to a range of important Environmental problems and to utilize this knowledge in making critical evaluations of these problems.