Full Article: PDF
Scientific Object Identifier: http://s-o-i.org/1.1/TAS-05-109-4
DOI: https://dx.doi.org/10.15863/TAS.2022.05.109.4
Language: English
Citation: Khalmanov, A., Nasimov, A., & Toshkuvatova, N. (2022). Studying the objects of environment PCB analysis in natural objects by gas chromatography with ECD. ISJ Theoretical & Applied Science, 05 (109), 50-59. Soi: http://s-o-i.org/1.1/TAS-05-109-4 Doi: https://dx.doi.org/10.15863/TAS.2022.05.109.4 |
Pages: 50-59
Published: 30.05.2022
Abstract: Twenty six samples for PCBs pollution in the central Region of Samarkand and Tashkent Region were investigated. Soil samples were collected from around of electricity supply of the Samarkand region and around Chirchik Transformer plant of the Tashkent region. The soil samples were extracted with chloroform mixture (1:1 v/v) for 4 hours. The final extract of 2.0 ml was analyzed for PCBs using a gas chromatograph equipped with 10 mCi 63Ni electron capture detector GC - ECD model 86/30. The retention time for the PCBs standard C=1mg/L were PCB 2,4,4’, 3.683 min; PCB 2,2’,5,5’, 3.963min; PCB 2,2’3,4,4’5,5’, 4,697 min; PCB2,2,3,4,5,5’ 5.237 min; PCB 2,3’4’4’5, 5.427min; PCB 2,2’4,4’5,5’ 5.67 min; and PCB 2,2’3,4,4’,5’ 6.290 min. Calibration curves for PCB 7 congeners were obtained, and the detection limits were estimated. We have used the standard solutions C=1mg/L and 10mg/L of PCB in isooctane for receiving calibration curves and identification for PCB 7 congeners. The variations of the microelements in soil around Chirchik Transformer plant were analyzed by the method of atomic absorption spectrometer “Saturn”. The mean concentration (in mg/kg) of the metals were Ca (416± 19,1) >Na (222 ± 13,6)>Cu(100±3,9)>Ni (87±5,1)>Pb(57,1±2,9)>Zn (40.0 ±2.5) >Co (29.0±1,9 ) > Cd(21.3±1,5) > Fe (18.0±1,3)> Mn (10.0±1,2)>Cl-(0,32±0,02). The variations in the levels of the microelements were in the order Ca >Na >Cu>Ni >Pb>Zn >Co > Cd > Fe> Mn >Cl-. Very few sites were found to be contaminated with metals, but the level of metal contamination was very low. There was no significant correlation between the PCBs and any of the metals. The sources of the PCBs and metal were anthropogenic.
Key words: the atmospheric aerosols, laser resonans-ioninazation spectroscopy, atom-ionization, cavity ring-down, polychlorinated biphenyl.
|
