Quality, Quantity and Origin of PAHs (Polycyclic Aromatic Hydrocarbons) in Lotic Ecosystem of Al-Hilla River, Iraq

Abstract

Abstract:The Euphrates River is one of the major rivers in Iraq. When it reaches north of Hilla city, it will be divided in two branches. One of these braches flows toward Hilla city. On this branch, six locations were studied for the water quality of the Euphrates water. The present paper is aimed to fill the gap of information of the presence of PAHs (poly aromatic hydrocarbons) in water and sediment of Al-Hilla River, as well as to determine the quality and quantity of some PAHs. The depth of the river ranges from 2 m to 6 m. The quality, quantity and the origin of PAHs were studied in the water and sediment of Al-Hilla River. In addition, some physical and chemical properties were studied at six sites along the studied area, for the period March, 2010 to February, 2011. Sixteen PAHs that are listed by USEPA (US Environmental Protection Agency) as priority pollutants (Nap (naphthalene), Acpy ,h)anthracene), B(ghi)P (benzo(ghi)perylene) and Ind (indeno (1,2,3-cd) pyrene)) were detected in Al-Hilla river. High concentrations of PAHs were detected in the sediment relative to that within the water. The present study revealed that the origin of PAHs in water and sediment might be the pyrogenic origin.

Distribution of Polycyclic Aromatic Hydrocarbons in Water and Sediments in the Euphrates River, Iraq

“…These compounds were selected because they are considered to be primary pollutants as described by the USEPA [13]. The results are consistent with two previous studies conducted on the Euphrates River and its branches [4,6].…”

“…The HMWCs (4-6 rings) had lower concentrations than the LMWCs, except for B(ghi)P, which may be high despite their decreased solubility in water and their lipophilic and hydrophobic properties. Similar results were previously found in Al-Hilla River [6] but not in the Klang Strait [28]. Based on the relationship between the calculated ratios and the origin of PAHs [28], it can be implied that the present results reveal a consistent pyrogenic origin; the ratio for Site 1 (0.52) reveals combustion of wood or kerosene, whereas the remaining five sites show combustion of vehicle fuel (Table -4).…”

“…In Iraq, no such major study has been performed. Hassan and his colleagues [3][4][5][6][7][8] started studying the effects of pollution in Euphrates River in the middle region of Iraq to clarify the extent of environmental degradation that occurred in Iraq and to move policy makers to take the environmental impacts of socio-political instability into account when making decisions that concern war and peace. The environmental effects are devastating, yet it is difficult to obtain critical environmental data.…”

“…HMWC were dominant in comparison to LMWC in both water and sediment samples. Hassan et al [6] investigated the distribution of PAH compounds in water and sediment samples from Al-Hilla River, They reported that the total concentrations were0.226 μg/lin water samples, dominated by the low molecular weight Acp, and 402.54 μg/gin sediment samples, dominated by the high molecular weight B(ghi)P [6].…”

“…Several studies showed that lighter PAHs dominated water samples, while heavier compounds dominated sediment samples [6,15,16]. In addition, the high concentrations of PAHs in riverine sediments caused by the industrial activities are not easy to remove [12].…”