Heterocyclic nitrogenous bases are one of the most important class of compounds containing N as a heteroatom, like pyridine and its derivatives. These compounds are of immense concern from point view of environment since they are known for their toxic and carcinogenic properties, lethal effect on natural biogenic environment and severe odour potential. There is a need to control these compounds from getting discharged into the environment. This paper addresses the different natural/anthropogenic sources which generate these pollutants, their toxicity profile, different physico-chemical treatment methods and especially focuses on biological methods of treatment and combination of these for the efficient removal to achieve a treated effluent quality fit for disposal without causing any damage to the environment. (C) 2007 Published by Elsevier Ltd.