This book is very helpful for the m.Sc. in zoology and environment study as well as more specific for doing research in the field of ecotoxicology and environment safety. This book also helpful for reserch scholars, post doctorates, scientists and fisheries students. It is provided information about ammonia and macromolecular contents and biomarkers (Enzymes). It is also provided the best materials and methods that can we use in ecotoxicology.