title: Assessment of persistent organochlorine pollutants in sediments from Lake Manzala, Egypt.
abstract: Organochlorine pesticides (OCPs) and polychlorinated biphenyls (PCBs) were determined in surface and core sediment samples collected from Manzala Lake, the largest of the Egyptian coastal lakes. Total concentrations of OCPs and ∑7 PCBs (ICES) in sediments ranged from 0.63 to 31.31 ng/g and 0.26 to 31.27 ng/g, respectively. Geographical distribution indicates that levels of contaminants were significantly higher in areas which are mainly influenced by municipal discharge, indicating significant sources of these compounds in urbanised areas. The composition of DDT and its metabolites suggest old input of DDT. The levels of contaminants in Manzala Lake were similar or lower than those observed in comparable areas worldwide. The profiles of ∑OCPs and ∑PCBs in a core from a site heavily impacted by sewage discharge have highest concentrations in the surface core section indicating recent inputs. Assessment of ecotoxicological risk indicated that sediments in two sites were likely to pose potential biological adverse impact.
authors.affiliation: Department of Environmental Sciences, Faculty of Science, Alexandria University, Moharrem Bek, Alexandria 21511, Egypt. asem.barakat@alex-sci.edu.eg
authors.forename: Assem O
authors.initials: AO
authors.lastname: Barakat
authors.forename: Alaa
authors.initials: A
authors.lastname: Mostafa
authors.forename: Terry L
authors.initials: TL
authors.lastname: Wade
authors.forename: Stephen T
authors.initials: ST
authors.lastname: Sweet
authors.forename: Nadia B
authors.initials: NB
authors.lastname: El Sayed
mesh_terms: D004534:Egypt; D004784:Environmental Monitoring; D019015:Geologic Sediments / Q000737:chemistry*; D006843:Hydrocarbons, Chlorinated / Q000032:analysis*; D060106:Lakes / Q000737:chemistry*; D010575:Pesticides / Q000032:analysis; D011078:Polychlorinated Biphenyls / Q000032:analysis; D014874:Water Pollutants, Chemical / Q000032:analysis*; D014877:Water Pollution, Chemical / Q000706:statistics & numerical data
chemical_list: D006843:Hydrocarbons, Chlorinated; D010575:Pesticides; D014874:Water Pollutants, Chemical; D011078:Polychlorinated Biphenyls