the biodegradable pollutants may be controlled at source by their treatment for reuse and recycling. The non-biodegradable substances can be removed by various methods which are as follows:-
1. Stabilization of ecosystem. The pollutants are checked a source and so not introduced in the environment. Harvesting and removal of biomass, trapping of nutrients, fish management etc.
2. Re utilization and recycling of waste. Industrial effluents i.e. chemicals, sewage, agricultural wastes, thermal pollutants may be recycled to generate cheaper fuel gas and electricity.
3. Removal of pollutants. Various pollutants are removed by absorption electrodyalysis, ion exchange, reverse osmosis.
4. Use of pollutant degrading genes. Certain genes can be used for degradation of environmental pollutants, e.g. genes in Pseudomonas putida and some sps. of the same genes are found to degrade toxic pollutants like toluence,chlorobenzoic acid, halogenated pesticides and other toxic substances. For every compound a separate plasmid is required. For detoxification and degradation of toxic chemicals specific genes present on plasmids enclose specific enzymes.