BIOREMEDIATION OF SOME TOXIC SUBSTANCES FROM WASTE WATER USING LIVING BIOMASS

Abstract

Water is indispensable for living life as safe and fresh drinking water is essential for existence. Only close to 1% of water reserves of the world is fresh water. As per, data provided by international organizations “World Water Council and the World Health Organization”, out of six people two or more are devoid of access to safe water for drinking purpose [1]. According to World Health Organization (WHO) and Environmental Protection Agency (EPA) any demonstrable and continuous breach of any biological or physical or chemical parameter of quality of water systems is termed as water pollution. In 21st century the most urgent environmental turmoil is water scarcity and pollution which is ranked as high as climate change [2]. This is caused by steep industrialization and metropolitan growth resulting in the deterioration of human health [3] and several ecosystems [4]. Industrial and agricultural activities causing discharge of heavy metals into aqueous streams is of special concern due to the recalcitrant nature of pollutants [5-6]. This is substantiated by a report of United Nations World Water Development which states the disposal of 2 million tonnes of waste per day into aqueous streams by these activities [7]. 1.2. POLLUTANTS The pollutants are defined as undesirable changes in the earth’s environment caused by natural or artificial inputs. The major sources of pollution are industrial, domestic and agricultural activities. Among the various forms of industrial pollution, the most common is water pollution. Some of the important pollutants and their impact on the environment have been discussed as follows: 1.2.1. Dyes Dyes are among the most recalcitrant organic pollutants discharged into fresh water from pharmaceutical, tanning, leather, textile, paper, paint and food processing industries [8-16]. There is a two-fold objective fulfilled while removing synthetic dyes from wastewater : first is removal of toxicity as some dyes and their degradation products