title: Persistent organic pollutants in the Olifants River Basin, South Africa: Bioaccumulation and trophic transfer through a subtropical aquatic food web.
abstract: This study investigates the trophic transfer of persistent organic pollutants (POPs: PCBs, PBDEs, OCPs and PFASs) in the subtropical aquatic ecosystem of the Olifants River Basin (South Africa) by means of trophic magnification factors (TMFs). Relative trophic levels were determined by stable isotope analysis. POP levels in surface water, sediment and biota were low. Only ∑DDTs levels in fish muscle (<LOQ-61ng/g ww) were comparable or higher than values from other temperate and tropical regions. Significant positive relationships between relative trophic level and PCB, DDT and HCH concentrations were observed so trophic levels play an important role in the movement of contaminants through the food web. TMFs were >1, indicating biomagnification of all detected POPs. Calculated TMFs for PCBs were comparable to TMF values reported from the tropical Congo River basin and lower than TMFs from temperate and arctic regions. For p,p'-DDT, a higher TMF value was observed for the subtropical Olifants River during the winter low flow season than for the tropical Congo river. TMFs of DDTs from the present study were unexpectedly higher than TMFs from temperate and arctic aquatic food webs. The fish species in the aquatic ecosystem of the Olifants River can be consumed with a low risk for POP contamination.
authors.affiliation: Systemic Physiological & Ecotoxicological Research, Department of Biology, University of Antwerp, Groenenborgerlaan 171, 2020 Antwerp, Belgium. Electronic address: vera_verhaert@hotmail.com.
authors.forename: Vera
authors.initials: V
authors.lastname: Verhaert
authors.affiliation: Systemic Physiological & Ecotoxicological Research, Department of Biology, University of Antwerp, Groenenborgerlaan 171, 2020 Antwerp, Belgium.
authors.forename: Nadine
authors.initials: N
authors.lastname: Newmark
authors.affiliation: Systemic Physiological & Ecotoxicological Research, Department of Biology, University of Antwerp, Groenenborgerlaan 171, 2020 Antwerp, Belgium.
authors.forename: Wendy
authors.initials: W
authors.lastname: D'Hollander
authors.affiliation: Toxicological Centre, University of Antwerp, Universiteitsplein 1, 2610 Wilrijk-Antwerp, Belgium.
authors.forename: Adrian
authors.initials: A
authors.lastname: Covaci
authors.affiliation: Department of Zoology, University of Johannesburg, PO Box 524, Auckland Park 2006, South Africa.
authors.forename: Wynand
authors.initials: W
authors.lastname: Vlok
authors.affiliation: Unit for Environmental Sciences and Management, Water Research Group, North-West University, Private Bag X6001, Potchefstroom 2520, South Africa.
authors.forename: Victor
authors.initials: V
authors.lastname: Wepener
authors.affiliation: Department of Biodiversity, University of Limpopo, Private Bag X1106, Sovenga 0727, South Africa.
authors.forename: Abraham
authors.initials: A
authors.lastname: Addo-Bediako
authors.affiliation: Department of Biodiversity, University of Limpopo, Private Bag X1106, Sovenga 0727, South Africa.
authors.forename: Antoinette
authors.initials: A
authors.lastname: Jooste
authors.affiliation: Systemic Physiological & Ecotoxicological Research, Department of Biology, University of Antwerp, Groenenborgerlaan 171, 2020 Antwerp, Belgium.
authors.forename: Johannes
authors.initials: J
authors.lastname: Teuchies
authors.affiliation: Systemic Physiological & Ecotoxicological Research, Department of Biology, University of Antwerp, Groenenborgerlaan 171, 2020 Antwerp, Belgium.
authors.forename: Ronny
authors.initials: R
authors.lastname: Blust
authors.affiliation: Systemic Physiological & Ecotoxicological Research, Department of Biology, University of Antwerp, Groenenborgerlaan 171, 2020 Antwerp, Belgium. Electronic address: Lieven.Bervoets@uantwerpen.be.
authors.forename: Lieven
authors.initials: L
authors.lastname: Bervoets
mesh_terms: D000818:Animals; D003634:DDT / Q000032:analysis; D004784:Environmental Monitoring; D005399:Fishes; D020387:Food Chain; D055768:Halogenated Diphenyl Ethers / Q000032:analysis; D011078:Polychlorinated Biphenyls / Q000032:analysis; D045483:Rivers / Q000737:chemistry*; D013019:South Africa; D014874:Water Pollutants, Chemical / Q000032:analysis*
chemical_list: D055768:Halogenated Diphenyl Ethers; D014874:Water Pollutants, Chemical; D003634:DDT; D011078:Polychlorinated Biphenyls
keywords: Bioaccumulation; Olifants River Basin; Persistent organic pollutants; Subtropical; Trophic magnification factors