Polychlorinated biphenyl residues and etiology of cancer: a case control study in the residents of Karachi city
By: Mohammad Attaullah, Masarrat J. Yousuf, Sohail Shaukat, Alia B. Munshi, Sobia Khawaja, Syed Ishtiaq Anjum
Key Words: Polychlorinated biphenyls, Gas Chromatography, Electron Capture Detector, Cancer, Environmental chemicals.
J. Bio. Env. Sci. 9(2), 212-221, August 2016.
Residues of Polychlorinated Biphenyls (PCBs) were comparatively evaluated in the serum samples of cancer patients and healthy residents of Karachi City. This was a preliminary work on the role of PCBs in the etiology of cancer in Pakistan. A random collection of fasting blood samples from diagnosed cancer patients having various malignancies and healthy humans was carried out with informed consent of the donors at various hospitals of Karachi. Serum was separated within 2 hours of collection and then analyzed for residues of the seven PCBs (PCB 28, PCB 52, PCB 101, PCB 138, PCB 153, PCB 180 and PCB 209) on Gas Chromatograph coupled with Electron Capture Detector (GC-ECD). PCBs were detected in 93.98% of the cancer cases and 93.75 % of the normal subjects. Mean level of total PCBs (ΣPCBs) was found significantly elevated in the cancer group (2.711 mg/kg) compared with the control group (0.536 mg/kg). PCB 52 was the most prevalent PCB congener with a mean level of 2.044 mg/kg in the cancer group and 0.134 mg/kg in the control group. It was observed that concentrations of PCBs increased linearly with the increasing age of the cancer patients. Highest mean concentration of ΣPCBs was found in the cases of Chronic Myeloid Leukemia as 11.962 mg/kg. In light of the obtained results, it has concluded that PCBs are positively associated with the etiology of cancer. Further research is recommended to know the exact role and mechanism of PCBs in the field of oncology.