Measurement of polychlorinated biphenyls (PCBs) in the soil samples of taleghan region and investigation the presence of biological agents capable of removing PCBs in these soil samples

The aim of the present study was to measure the concentration of poly- chlorobiphenyls in the soil around power transformers in Taleghan region of Karaj, and to Identification and extraction of bacteria that degrade PCBs. for biological removal in the environment

For this purpose, soil sampling around power transformers of 5 stations in different places was done with the help of GPS device. Soil sampling was performed from a depth of 20 cm in sterile conditions and samples were kept in glass containers. LB broth Blood Agar and McConkey culture media were used to identify and determine the bacteria degrading PCBs.

Five samples were examined of which only 2 samples were positive for PCBs contamination and microbial exploration was performed in these 2 samples. In one of the samples, the amount of PCBs was equal to 3 PPM, while in the second sample, the total amount of PCBs was estimated to be less than 0/02 PPM. The two samples that were positive for PCBs, were cultured both directly and diluted. In sample 1 and 2, which were cultured directly, gram negative bacilli grew. In the diluted sample 1, no bacteria grew, while in the diluted sample 2, cocci were grown and in gram coloring it turned purple so it was gram positive. In fact directed sample 1 and 2 contained bacilli and turned red (gram negative) in response to gram coloring.

The use of these bacteria to remove the compounds of PCBs is one of the useful ways to reduce pollution in these places, with the least harmful effect on the environment and at the same time the most profitable sectors of the industry.