Identification of polycyclic aromatic hydrocarbons in groundwater in the wells of Al-Zubair district near the Basra refinery, southern Iraq

Abstract

The current study was conducted to estimate the concentrations of polycyclic aromatic petroleum hydrocarbons with their dissolved and suspended particles in the groundwater of eight wells, the six wells from w1 to w6 close to the refinery area about half a kilometer to three kilometers and the two wells w7 and w8 are away from the site about 12.5 km (wells of control), in The area surrounding the South Refinery (Al-Shuaiba) Al-Zubayr district in Basra Governorate, southern Iraq. Sixteen compounds of PAHs in water were identified in both the dissolved and suspended parts in the spring of 2016 due to the high value of dissolved and suspended hydrocarbons and the transport of petroleum hydrocarbon pollutants through the rain that transport the particles and dissolved materials through the pores of soil to groundwater. The total concentrations of PAHs dissolved in water ranged between 7205 ng ∕ l in well W1. In comparison, the lowest value was 39.1 ng ∕ l in well W8. The highest concentration of Phenanthrene in well W1 was 3472 ng ∕ l, and the lowest concentration of Benzo (a) Pyrene was 0.37 ng ∕ l for well W8. Benzo (b) Fluoranthene was recorded predominantly in the dissolved part. The total concentrations of PAHs ranged from total suspended in water, between the highest value of 9334 ng/ g dry weight in well W1. The lowest value of 370 ng/ g dry weight in well W8 and the most abundant compound is Fluorene, as Dibenzo (a, h) anthracene recorded the highest concentration of 6689 ng/ g dry weight in well W3 and the lowest concentration of 13 ng ∕ g the compound Benzo (a) anthracene was in well W8. It was concluded that oil refinery has a significant impact in causing pollution of nearby water wells with some dangerous and carcinogenic polycyclic hydrocarbon pollutants .