Industrial waste water and sediment containing heavy metals causes many ecological and health related problems. Many conventional methods were already being used to decontaminate the environment from adverse effect of these pollutants but yet most of the methods used are very expensive and far away from their best possible performance. The capability of microorganisms to bind metal ions is a well-known trend. Different experimental data are documented and presented for different metals and biomass types. In this review a brief overview of the potential of biosorbents and biosorption processes were critically reviewed. This briefly describes biosorption process and some of the analysis of different lowcost biosorbents used for heavy metal remediation from waste stream.

Heavy metals tolerant bacteria were isolated from electroplating industry. The activities of electroplating and metal processing industries are regarded as one of the major source of heavy metal pollution. This paper present about the role of microorganisms in heavy metal removal from industrial waste water. In this study 21 bacterial colonies were isolated and tested in the presence of different metals. After screening five best isolates which showed high resistances were selected. The result reveals that all isolates MH1, MH4, MH6 MH15 and MH21 were able to tolerate 50 mg/l of cr, cu, pb and cd. Isolates MH1 and MH21 tolerate 200 mg/l of cadmium while isolate MH4 also showed high degree of resistance to copper. These indicated that the isolates can be used efficiently in removal of heavy metals in contaminated industrial effluents.

Extensive use of carbofuran insecticide harms the environment and human health. Carbofuran is an endocrine disruptor and has the highest acute toxicity to humans than all groups of carbamate pesticides used. Carbofuran is highly mobile in soil and soluble in water with a lengthy half-life (50 days). Therefore, it has the potential to contaminate groundwater and nearby water bodies after rainfall events. A bacterial strain BRC05 was isolated from agricultural soil characterized and presumptively identified as Enterobacter sp. The strain was immobilized using gellan gum as an entrapment material. The effect of different heavy metals and the ability of the immobilized cells to degrade carbofuran were compared with their free cell counterparts. The results showed a significant increase in the degradation of carbofuran by immobilized cells compared with freely suspended cells. Carbofuran was completely degraded within 9 h by immobilized cells at 50 mg/L, while it took 12 h for free cells to degrade carbofuran at the same concentration. Besides, the immobilized cells completely degraded carbofuran within 38 h at 100 mg/L. On the other hand, free cells degraded the compound in 68 h. The viability of the freely suspended cell and degradation efficiency was inhibited at a concentration greater than 100 mg/L. Whereas, the immobilized cells almost completely degraded carbofuran at 100 mg/L. At 250 mg/L concentration, the rate of degradation decreased significantly in free cells. The immobilized cells could also be reused for about nine cycles without losing their degradation activity. Hence, the gellan gum-immobilized cells of Enterobacter sp. could be potentially used in the bioremediation of carbofuran in contaminated soil.

P ESTICIDES play an important role in preventing insect pests and weeds in crops. However, excessive use of pesticides has been known to be unsafe, due to their toxicity to non-target organisms and the ecosystem. Biodegradation is an innovative approach for decontaminating pesticide pollution. However, compared with the list of extensively used pesticides there are few well-characterized strains of microbes that transform pesticides into less-toxic or more labile products at environmentally useful rates. Fortunately, the technology required to isolate and characterize such microbial strains has improved immensely in the recent years. Furthermore, recent experimental developments have made practical the modification of potentially beneficial biodegradation genes so that they may be optimally expressed in a wide range of microbial species. This reviews article explore the recent studies that have focused on biodegradation of pesticide residues, the mechanism of microbial degradation of pesticides, the factors that affect the degradation of pesticides and the new application of microbial degradation of pesticides.

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Carbofuran is a broad spectrum carbamate pesticide often used to control pests in the agricultural sector. However, despite its ability to effectively kill the insects in the farms, health associated problems are still been reported due to its higher level of toxicity. The biodegradation is an effective method used for the removal of these compound from the environment since previous methods using a chemical process of degradation prove to be ineffective due to the presence of highly stable bonds. Bacterial strain BRC05 isolated from vegetable plantation area of Cameron Highlands was found to have carbofuran-degrading ability. The morphology and growth at different concentration of carbofuran were studied. The growth of the isolate was evaluated in Carbofuran medium under stable and shaking conditions. The gram-negative motile and rod-shaped BRC05 show good growth on Carbofuran medium after 12 hours of incubation. The optical densities of the isolate was more under shaking condition and differed significantly than under static conditions. There is no significant difference (p>0.05) between growth at 25 and 50 mg/l under static conditions.  At 25 mg/l under shaking condition the insecticide has less effect on the growth of the isolate. It was found that BRC05 could grow well and reach the largest biomass in the medium containing 25 mg/l of carbofuran and could keep active growth even in medium with high concentration of carbofuran 100 mg/l. These showed that the bacteria could grow and remove carbofuran in soils effectively and safely.

Soil is a composite system which consists of organic and inorganic matter that directly or indirectly supports plant and animal life and is a crucial component of our rural and urban environments (Emanuel, 2015). Trace elements are natural constituents of soil which come from rocks and soils through the processes of erosion, transport and deposition. They can also be derived from anthropogenic sources in which case they are incorporated into sediments as artificial pollutants from industrial or urban releases and wastes (Bermea et al., 2002). Their low Igeo index are usually safe, but increased in Igeo index of these elements in the environment can be significantly destructive to plants and animal life (Macfarlane & Burchett, 2000). As such soil is feasibly the most endangered component of our environment which is open to potential contamination by a variety of different pollutants arising from majorly human activities such as nuclear,