title: Recognizing different impacts of human and natural sources on the spatial distribution and temporal trends of PAHs and PCBs (including PCB-11) in sediments of the Nador Lagoon (Morocco).
abstract: The Nador Lagoon holds a major interest in present-day Moroccan socioeconomic development. This environment is exposed to a number of potential polluting sources, such as mine tailings, urban and industrial dumping, and untreated wastewater inputs from surrounding cities. The aim of this study was to assess concentrations and trends of persistent contaminants such as PCBs and PAHs and to identify their origin. The non-Aroclor PCB-11 was determined for the first time in the lagoon sediments. Chronology and source assessment helped identifying the timing and nature of inputs and post-depositional processes controlling the two classes of contaminants: PAHs present a typical mixed petrogenic signature, with the exception of sediments deposited in the period 1930-1960 near the city of Nador, when pyrogenic inputs prevailed; PCBs show signs of microbial anaerobic degradation from 1950 to 1990, probably linked to changing hydrodynamic conditions in the South-Western part of the lagoon where agricultural inputs are dominant. The presence of PCB-11 is linked to specific productions and might be affected by degradation processes. Presently, different land uses (e.g., urban and agricultural areas) appear to be the key factors in controlling the level and composition of PAHs and PCBs in lagoon sediments. Total PAH and PCB levels are low (from 21.6 to 108 ng g(-1) and from 2.50 to 20.7 ng g(-1), respectively) but recent increasing values and the potential threat to humans and biota require continuous and constant monitoring.
authors.affiliation: CNR-Institute of Marine Sciences, Via Gobetti 101, Bologna, Italy.
authors.forename: Silvia
authors.initials: S
authors.lastname: Giuliani
authors.affiliation: Dept. of Environmental Sciences, Informatics and Statistics, Ca' Foscari Univ. of Venice, Dorsoduro 2137, Venice, Italy; CNR-Institute for the Dynamics of Environmental Processes, Dorsoduro 2137, Venice, Italy.
authors.forename: Rossano
authors.initials: R
authors.lastname: Piazza
authors.affiliation: Dept. of Earth Sciences and Oceanography, Univ. of Tangier, Tangier, Morocco; Polydisciplinary Faculty of Larache, BP 745 Route de Rabat, Larache, Morocco.
authors.forename: Bouchta
authors.initials: B
authors.lastname: El Moumni
authors.affiliation: Dept. of Environmental Sciences, Informatics and Statistics, Ca' Foscari Univ. of Venice, Dorsoduro 2137, Venice, Italy; CNR-Institute for the Dynamics of Environmental Processes, Dorsoduro 2137, Venice, Italy.
authors.forename: Fabio Paolo
authors.initials: FP
authors.lastname: Polo
authors.affiliation: CNR-Institute for the Dynamics of Environmental Processes, Dorsoduro 2137, Venice, Italy; Dept of Physical Sciences, Earth and Environment, Univ. of Siena, Via Laterina 8, Siena, Italy.
authors.forename: Marco
authors.initials: M
authors.lastname: Vecchiato
authors.affiliation: CNR-Institute of Marine Sciences, Via Gobetti 101, Bologna, Italy.
authors.forename: Stefania
authors.initials: S
authors.lastname: Romano
authors.affiliation: Dept. of Environmental Sciences, Informatics and Statistics, Ca' Foscari Univ. of Venice, Dorsoduro 2137, Venice, Italy.
authors.forename: Stefano
authors.initials: S
authors.lastname: Zambon
authors.affiliation: CNR-Institute of Marine Sciences, Via Gobetti 101, Bologna, Italy.
authors.forename: Mauro
authors.initials: M
authors.lastname: Frignani
authors.affiliation: CNR-Institute of Marine Sciences, Via Gobetti 101, Bologna, Italy.
authors.forename: Luca Giorgio
authors.initials: LG
authors.lastname: Bellucci
mesh_terms: D000383:Agriculture; D004784:Environmental Monitoring; D019015:Geologic Sediments / Q000737:chemistry*; D006801:Humans; D009018:Morocco; D011078:Polychlorinated Biphenyls / Q000032:analysis*; D011084:Polycyclic Aromatic Hydrocarbons / Q000032:analysis*; D012623:Seawater / Q000737:chemistry*; D014874:Water Pollutants, Chemical / Q000032:analysis*
chemical_list: D011084:Polycyclic Aromatic Hydrocarbons; D014874:Water Pollutants, Chemical; D011078:Polychlorinated Biphenyls
keywords: Contamination sources; Nador Lagoon; PAHs; PCBs