REGIONAL AND SEASONAL VARIATIONS OF POLYCHLORINATED BIPHENYLS (PCBS) IN WATER OF SHATT AL-ARAB RIVER, IRAQRafid A.T. Al-Zabad, Ayad H.D. Al-Khafaji and Hamid T. AL-SaadAbstract The concentrations of polychlorinated biphenyls (PCBs) were determined from Autumn season 2019 to summer season 2020 at six sites they are: (Al-Qurna, Al-Deer, Al-Qarma, Al-Ashar, Abu-Al-khasib, Al- Fao) in Shatt Al-Arab river, Basrah city, Iraq. Water samples were taken at each site and were analyzed using gas chromatography-mass spectrometry (GCâMS) type Agilent 7820A for PCB levels. The results indicate that PCBs are detected in all water samples and its concentration range from 2.61ng /l to 6.65 ng/l, 14.01ng /l to 21.19 ng /l, 7.67ng /l to 20.90 ng /l and 8.36 ng /l to 15.12 ng /l in Autumn, Winter, Spring and Summer seasons, respectively. The Al-Qurna and Al-Ashar sites were found to have the highest and lowest mean levels of PCB concentrations 0.201ng /l and 24.83ng /l, respectively. Total congener PCB (PCB 18, 29, 31,28, 44, 52, 101, 141, 149, 138,153, 189, and 194) concentrations at the water samples for all sites ranged from 2.61 ng/l in Al-Qurna station during autumn season to 24.83 ng/l in Al-Ashar station during winter season. Ãhexa-PCBs and Ãtri-PCBs were dominating in comparison with others PCBs congeners. This study is a first of its kind in the region and could give available information and could be uses as a baseline study in the futures. |