Regional and Seasonal Variation of Polycyclic Aromatic Hydrocarbons in Water and Mollusca at Quarna North of Shatt AL-Arab River

Abstract

Distribution and seasonal variations and sources of of the sixteen polycyclic aromatic hydrocarbons (PAHs) was studied in surface water and and fuor species of molluscs ( Theodoxus Jordani , Melanoides taberculata Melanopsis nodosa, Bellamya bengalensis ) from three stations at Al-Quarna in Shatt Al Arab river during the low tide period from September, 2018 to March, 2019 . Liquid-liquid extraction was used for water samples, while PAHs in molluscs were extracted using Soxhlet Extraction and finally analyzed by means of gas chromatography. physical and chemical parameter were measured such as . Water Temperature range from (13°C to 39°C), Dissolved oxygen range from (6.5 mg/l to 3.84 mg/l),PH range from (8.15-7.17) and Electrical conductivity (2.59 ms/cm- 4.75 ms/cm). Results of PAHs in water samples was ranged from (1.4754ng / l) during summer in the first station to (3.4215ng / l) during winter at the third station. While the total PAHs in molluscs range from 0.876 ng/g dry weight in the T .jordani in station 1during summer to 9.093 ng/g dry weight in the B.bengalensis during winter . The Highest concentration of PAHs in the four species were arranged as fellow : Bellamya bengalensis ˃ Melanopsis nodosa ˃ Melanoides taberculata ˃ Theodoxus Jordani. When we compares the concentration TPHs in water and molluscs with other study it allies within these concentration. Keywords: PAH, water, Mollusca, Pollution,Qurna,ShattAL-Arab River,Basrah,Iraq DOI : 10.7176/JNSR/9-14-05 Publication date :July 31 st 2019