title: Trace metals and persistent organic pollutants in sediments from river-reservoir systems in Democratic Republic of Congo (DRC): Spatial distribution and potential ecotoxicological effects.
abstract: This paper discusses the occurrence and spatial distribution of metals and persistent organic pollutants (POPs: including organochlorine pesticides (OCPs), polychlorinated biphenyls (PCBs), Polybrominated diphenyl ethers (PBDEs), and polycyclic aromatic hydrocarbons (PAHs) in sediments from a river-reservoir system. Surface sediments were sampled from thirteen sites of the Congo River Basin and Lake Ma Vallée, both situated in the vicinity of the capital city Kinshasa (Congo Democratic Republic). Sediment qualities were evaluated using toxicity test based on exposing Ostracods to the sediment samples. The highest metal concentrations were observed in sediments subjected to anthropogenic influences, urban runoff and domestic and industrial wastewaters, discharge into the Congo River basin. Ostracods exposed to the sediments resulted in 100% mortality rates after 6d of incubation, indicating the ultimate toxicity of these sediments as well as potential environmental risks. The POPs and PAHs levels in all sediment samples were low, with maximum concentration found in the sediments (area of pool Malebo): OCP value ranged from 0.02 to 2.50 with ∑OCPs: 3.3μgkg(-1); PCB ranged from 0.07 to 0.99 with Total PCBs (∑7×4.3): 15.31μgkg(-1); PAH value ranged from 0.12 to 9.39 with ∑PAHs: 63.89μgkg(-1). Our results indicate that the deterioration of urban river-reservoir water quality result mainly from urban stormwater runoff, untreated industrial effluents which discharge into the river-reservoirs, human activities and uncontrolled urbanization. This study represents useful tools incorporated to evaluate sediment quality in river-reservoir systems which can be applied to similar aquatic environments.
authors.affiliation: Institut Supérieur des Techniques Médicales/Kinshasa, Section Nutrition diététique, B.P. 774, Kinshasa XI, People's Republic of Congo.
authors.forename: Paola M
authors.initials: PM
authors.lastname: Mwanamoki
authors.affiliation: Faculty of Science, Forel Institute and Institute of Environmental Sciences, University of Geneva, CP 416, 1290 Versoix, Switzerland; Postgraduate and Research Department of Zoology, Jamal Mohamed College, Tiruchirappalli 620020, Tamil Nadu, India.
authors.forename: Naresh
authors.initials: N
authors.lastname: Devarajan
authors.affiliation: Faculty of Science, Forel Institute and Institute of Environmental Sciences, University of Geneva, CP 416, 1290 Versoix, Switzerland.
authors.forename: Florian
authors.initials: F
authors.lastname: Thevenon
authors.affiliation: Faculty of Science, Forel Institute and Institute of Environmental Sciences, University of Geneva, CP 416, 1290 Versoix, Switzerland.
authors.forename: Niane
authors.initials: N
authors.lastname: Birane
authors.affiliation: Central Environmental Laboratory (GR-CEL), Ecole Polytechnique Fédérale de Lausanne (EPFL), 1015 Lausanne, Switzerland.
authors.forename: Luiz Felippe
authors.initials: LF
authors.lastname: de Alencastro
authors.affiliation: Central Environmental Laboratory (GR-CEL), Ecole Polytechnique Fédérale de Lausanne (EPFL), 1015 Lausanne, Switzerland.
authors.forename: Dominique
authors.initials: D
authors.lastname: Grandjean
authors.affiliation: University of Kinshasa, Faculty of Science, Department of Chemistry, B.P. 190, Kinshasa XI, People's Republic of Congo.
authors.forename: Pius T
authors.initials: PT
authors.lastname: Mpiana
authors.affiliation: Postgraduate and Research Department of Zoology, Jamal Mohamed College, Tiruchirappalli 620020, Tamil Nadu, India.
authors.forename: Kandasamy
authors.initials: K
authors.lastname: Prabakar
authors.affiliation: Université Pédagogique Nationale (UPN), Croisement Route de Matadi et Avenue de la Libération, Quartier Binza/UPN, B.P. 8815, Kinshasa, People's Republic of Congo.
authors.forename: Josué I
authors.initials: JI
authors.lastname: Mubedi
authors.affiliation: University of Kinshasa, Faculty of Science, Department of Chemistry, B.P. 190, Kinshasa XI, People's Republic of Congo.
authors.forename: Christophe G
authors.initials: CG
authors.lastname: Kabele
authors.affiliation: Faculty of Science, Forel Institute and Institute of Environmental Sciences, University of Geneva, CP 416, 1290 Versoix, Switzerland.
authors.forename: Walter
authors.initials: W
authors.lastname: Wildi
authors.affiliation: Faculty of Science, Forel Institute and Institute of Environmental Sciences, University of Geneva, CP 416, 1290 Versoix, Switzerland; University of Kinshasa, Faculty of Science, Department of Chemistry, B.P. 190, Kinshasa XI, People's Republic of Congo; Université Pédagogique Nationale (UPN), Croisement Route de Matadi et Avenue de la Libération, Quartier Binza/UPN, B.P. 8815, Kinshasa, People's Republic of Congo. Electronic address: john.pote@unige.ch.
authors.forename: John
authors.initials: J
authors.lastname: Poté
mesh_terms: D002947:Cities; D015023:Democratic Republic of the Congo; D054750:Ecotoxicology; D004784:Environmental Monitoring / Q000379:methods; D019015:Geologic Sediments / Q000032:analysis*; D055768:Halogenated Diphenyl Ethers / Q000032:analysis; D006801:Humans; D006843:Hydrocarbons, Chlorinated / Q000032:analysis; D060106:Lakes / Q000032:analysis; D008670:Metals / Q000032:analysis; D010575:Pesticides / Q000032:analysis; D011078:Polychlorinated Biphenyls / Q000032:analysis; D011084:Polycyclic Aromatic Hydrocarbons / Q000032:analysis; D045483:Rivers / Q000737:chemistry*; D014131:Trace Elements / Q000032:analysis; D014874:Water Pollutants, Chemical / Q000032:analysis*; D060753:Water Quality
chemical_list: D055768:Halogenated Diphenyl Ethers; D006843:Hydrocarbons, Chlorinated; D008670:Metals; D010575:Pesticides; D011084:Polycyclic Aromatic Hydrocarbons; D014131:Trace Elements; D014874:Water Pollutants, Chemical; D011078:Polychlorinated Biphenyls
keywords: Congo River basin; PAHs; PCBs; Sediments; Toxic metals; Toxicity test