title: Occurrence and sources of polar lipid tracers in sediments from the Shatt al-Arab River of Iraq and the northwestern Arabian Gulf.
abstract: Shallow surface sediment samples from the southern part of the Shatt al-Arab River estuary of Iraq and the northwestern Arabian Gulf were analyzed for polar lipid compounds including n-alkanoic acids, n-alkanols, steroids and triterpenoids. The results showed that the n-alkanoic acids, methyl n-alkanoates and n-alkanols typically ranged from C12 to C32 with total concentrations of 3.2 to 108.2 μg g(-1)dwt sample, from C12 to C30 with totals of 1.1 to 18.9 μg g(-1)dwt sample, and from C14 to C32 at 1.8 to 112.6 μg g(-1)dwt sample, respectively. Steroids and triterpenoids were detected and included stenols, stanols, stenones, stanones, tetrahymanol, tetrahymanone and extended ββ-hopanes. The total steroid concentrations ranged from 2.8 to 78.4 μg g(-1)dwt sample, whereas the triterpenoids varied from 0.05 to 7.6 μg g(-1)dwt sample. The simple regression analysis of the results and the spatial distribution patterns of the identified organic tracers indicated that the inter-compound relationships were related mainly to their major sources. Cluster analysis and principal component analysis (PCA) of data set showed that the sampling sites are similar. These sources were allochthonous (terrestrial vegetation), autochthonous (plankton residues and bacteria in the sediments) and anthropogenic (sewage and petroleum).
authors.affiliation: Department of Plant Protection and Chair of Green Energy Research, College of Food and Agriculture Sciences, King Saud University, P. O. Box 2460, Riyadh 11451, Saudi Arabia; College of Earth, Ocean and Atmospheric Sciences, Oregon State University, Corvallis, OR 97331, USA; Department of Earth and Environmental Sciences, Faculty of Sciences, Sana'a University, Sana'a, Yemen.
authors.forename: Ahmed I
authors.initials: AI
authors.lastname: Rushdi
authors.affiliation: Department of Plant Protection and Chair of Green Energy Research, College of Food and Agriculture Sciences, King Saud University, P. O. Box 2460, Riyadh 11451, Saudi Arabia; Department of Chemistry, Oregon State University, Corvallis, OR 97331, USA.
authors.forename: Bernd R T
authors.initials: BR
authors.lastname: Simoneit
authors.affiliation: Delta Research Group, Marine Sciences Center, Basra University, Basra, Iraq.
authors.forename: Ali A Z
authors.initials: AA
authors.lastname: Douabul
authors.affiliation: Department of Plant Protection and Chair of Green Energy Research, College of Food and Agriculture Sciences, King Saud University, P. O. Box 2460, Riyadh 11451, Saudi Arabia.
authors.forename: Khalid F
authors.initials: KF
authors.lastname: Al-Mutlaq
authors.affiliation: Department of Plant Protection and Chair of Green Energy Research, College of Food and Agriculture Sciences, King Saud University, P. O. Box 2460, Riyadh 11451, Saudi Arabia.
authors.forename: Aarif H
authors.initials: AH
authors.lastname: El-Mubarak
authors.affiliation: Center for Environment and Water, King Fahd University of Petroleum and Minerals, Dhahran 31261, Saudi Arabia.
authors.forename: Mohammed
authors.initials: M
authors.lastname: Qurban
authors.affiliation: College of Earth, Ocean and Atmospheric Sciences, Oregon State University, Corvallis, OR 97331, USA.
authors.forename: Miguel A
authors.initials: MA
authors.lastname: Goni
mesh_terms: D004784:Environmental Monitoring; D019015:Geologic Sediments / Q000737:chemistry*; D007493:Iraq; D008055:Lipids / Q000032:analysis; D045483:Rivers / Q000737:chemistry*; D013256:Steroids / Q000032:analysis; D014874:Water Pollutants, Chemical / Q000032:analysis*
chemical_list: D008055:Lipids; D013256:Steroids; D014874:Water Pollutants, Chemical
keywords: GC–MS; Iraq; Polar compounds; Shatt al-Arab; UCM