In the 1980s, the use of organic pollutants called polychlorinated biphenyls (PCBs) was banned, but they are still present in the environment and have negative effects on ecosystems and human health. The fate of PCBs in soil is determined by the following processes: adsorption to soil particles, degradation and transport (evaporation, sedimentation, assimilation, etc.). The best known techniques for bioremediation of PCB-contaminated soils are phytoremediation, rhizoremediation and mycoremediation. The aim is to find the most effective bioremediation method, or a combination of several techniques, to reduce PCB levels in soil to a minimum. It is necessary to investigate which organisms are most successful in degrading PCBs in soil and what can be done to accelerate the bioremediation processes. To summarise the literature, bioremediation can remove more than 50% of PCBs of the initial concentration in a period of 6 months. In combination, different communities of organisms (plants, bacteria, fungi) can remove more than 80% of PCBs in the same period of time. As a rule, bioremediation does not interfere with the basic composition of the environment. The problem of PCBs in soil is also a problem in Slovenia, and it is worth finding effective solutions to reduce pollution in our neighbourhood.
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