PCBs generally refers polychlorinated biphenyls

PCBs generally refers polychlorinated biphenyls, a human manufactured organic group of chemicals of chlorinated hydrocarbons with chemical formula C₁₂H_10-xCl_x. These chemicals are basically used in electrical transformers and capacitors, oil paints, hydraulic systems oil, rubber products, dye pigments and carbon paper. The most common trade name of PCBs is Aroclor. PCBs naturally undergo cycles in the environment through air, water and in the soil. PCBs components do not readily breakdown and it is anticipated that once in the environment it would stay for longer periods. In our case PCBs would probably leak into the stream and be transported downstream in lighter PCBs quantities to the furthest downstream from the source point of contamination. PCBs have capabilities to accumulate on plant parts for example on the leaves and also be absorbed into bodies of organisms. In our case scenario the human activity downstream include fishing and irrigation of food crops, PCBs in the stream water can be easily absorbed into the fish and also accumulate on the food crop being irrigated. In the case that PCBs leak into the stream it would be dangerous to the human life with great risks of cancerous infections and adverse effects on the immune system, endocrine system and reproduction system (Barry, 1986).