The relationship between physicochemical factors of industrial wastewater and resistant bacteria

After gathering a few samples of wastewater from Isfahan industrial units, the amount of their pollution has been measured by specifying the amount of heavy metals, BOD, COD and TOC. Besides, heavy metal resistant microorganism were isolated and also the percentage of their resistance was calculated. The relationship between physicochemical factors of these samples including BOD, COD, pH and the existing metals with resistant bacteria is discussed and examined. According to the obtained results, EC and pH are not related with the percentage and presence of resistant microorganisms. Between the concentration of Pb and Cd with the rate of BOD, a positive relationship was observed. The percentage of microorganisms resistant to zn and Cd showed a positive relationship with the concentration of these metals in wastewater and with the rate of BOD and COD, so that with an increase in the concentration of these metals, BOD, COD and the percentage of the resistant microorganisms increas, as well.