The pace of change in environmental biochemistry has continued unabated since 1980. This text discusses the nature of these recent changes and developments, without compromising its principal subject matter. While compiling this book, a serions view has been kept in mind that environmental biochemistry is essentially different from biochemistry. Wherever necessary, diagrams and structures of compounds have been used this text is suitable for undergraduate and postgraduate students of environmental biochemistry, environmental science, organic chemistry, genetics, and related disciplines.