Status of oil pollution in water and sediment from Shatt Al-Arab Estuary and North-West Arabian Gulf

Abstract

In the present study, an attempt was made to study the levels of petroleum hydrocarbon residues in Water and Sediment samples collected from ten stations at the region of Shatt Al-Arab Estuary and North-West of the Arabian Gulf. The water and sediment samples were analyzed by utilizing the spectrofluorometry technique. The results of the present research obviously indicated a degree of oil pollution, however, still lower in magnitude when compared with status in some other regional sites. The obtained levels of petroleum hydrocarbons in water was ranged from (3.09 µg/l) at station 7 to (30.87 µg/l) at station 9 while in sediment ranged from (19.43 µg/g) dry weight  at station 4 to (49.09 µg/g) dry weight at station 9. In order to give a better evaluation of the petroleum hydrocarbon levels in the sediments, the Total Organic Carbon (TOC) percentage and grain size analyses were done by granulometry technique on selected slips of the bulk sediments obtained for this purpose. The mean percent TOC estimations ranged from 0.1 at Station 4 to 1.34 at Station 9. The mean values obtained in this study indicated that the petroleum hydrocarbon levels in the sediment samples are lower than the levels in sediment samples obtained with similar methodology and analyses in some of the Gulf States and countries in close vicinity of the region. The major pollution sources may involve tanker and boat discharges and activities, municipal sewage and rural runoff from land. Also, discharges and effluents from oil refineries, electricity generating station and industrial activities into the Basrah city are obvious.