Book excerpt: Pollution is undesirable state of the natural environment being contaminated with harmful substances as a consequence of human activities so that the environment becomes harmful or unfit for living things; especially applicable to the contamination of soil, water, or the atmosphere by the discharge of harmful substances. In addition to the harm to living beings, both present or future and known or unknown, pollution cleanup and surveillance are enormous financial drains of the economies of the world. This book focuses on issues and developments critical for the field.