Browsing by Author "Lyche, Jan L."

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    Persistent Organic Pollutants (Pops) And Per- and Polyfluoroalkyl Substances (Pfass) in Liver from Wild and Farmed Tilapia (Oreochromis Niloticus) from Lake Kariba, Zambia: Levels and Geographic Trends and Considerations in Relation to Environmental Quality Standards (Eqss)
    (ELSEVIER, 2023) Simukoko, Chalumba K.; Mwakalapa, Eliezer B.; Muzandu, Kaampwe; Mutoloki, Stephen; Evensen, Øystein; Ræder, Erik M.; Müller, Mette B.; Polder, Anuschka; Lyche, Jan L.
    The current study was carried out to investigate a wide variety of persistent organic pollutants (POPs) in wild and farmed tilapia (Oreochromis niloticus) in Lake Kariba, Zambia, and assess levels of POPs in relation to Environ- mental Quality Standards (EQSs). Concentrations of organochlorine pesticides (OCPs), polychlorinated biphenyls (PCBs), polybrominated diphenyls (PBDEs), and perfluoroalkyl substances (PFASs) were determined in liver samples of tilapia. PFASs compounds PFOS, PFDA and PFNA were only detected in wild fish, with the highest median PFOS levels in site 1 (0.66 ng/g ww). Concentrations of POPs were in general highest in wild tilapia. The highest median ∑DDTs (93 and 81 ng/g lw) were found in wild tilapia from sites 1 and 2, respectively 165 km and 100 km west of the fish farms. Lower DDE/DDT ratios in sites 1 and 3 may indicate relatively recent exposure to DDT. The highest median of ∑17PCBs (3.2 ng/g lw) and ∑10PBDEs (8.1 ng/g lw) were found in wild tilapia from sites 1 and 2, respectively. The dominating PCB congeners were PCB-118, -138, 153 and 180 and for PBDEs, BDE-47, -154, and 209. In 78% of wild fish and 8% of farmed fish ∑6PBDE concentrations were above EQSbiota limits set by the EU. This warrants further studies.
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    Spatial Variation in Contaminant Occurrence in Marine Fishes and Prawns from Coastal Tanzania
    (Environmental Toxicology and Chemistry, 2022) Haarr, Ane; Mwakalapa, Eliezer B.; Lyche, Jan L.; Mmochi, Aviti J.; Polder, Anuschka; Ruus, Anders; Borgå, Katrine
    There are limited data on organic contaminants in marine biota from coastal Tanzania, especially on the occurrence of industrial‐use contaminants such as polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs). The present study, performed in 2018–2019 in coastal Tanzania and Zanzibar Island, aimed at assessing spatial variation in the occurrence of PCBs; brominated flame retardants (BFRs), including PBDEs; and organochlorine pesticides, including dichlorodiphenyltri- chloroethane (DDT), among three locations that differ in degree of anthropogenic activity. Analyzed samples included edible tissues of marine fishes and prawns representing different trophic levels and habitats. The results indicate a mainland–island difference, with fishes and prawns collected on Zanzibar having significantly lower PCB and DDT concentrations but higher concentrations of hexachlorobenzene compared to the two mainland locations. The highest contaminant concentrations were found in fishes and prawns collected around central Dar es Salaam harbor, with median ΣPCBs ranging from 22.3 to 577 ng/g lipid weight and ΣDDTs from 22.7 to 501 ng/g lipid weight, suggesting local sources. Concentrations of PBDEs were similar among locations, suggesting more diffuse sources. None of the “newer‐type” BFRs, including compounds introduced as replacements for PBDEs, were detected in the present study. Stable isotope values of carbon (δ13C) and nitrogen (δ15N) varied among locations, and the relationship between contaminants and δ15N varied among locations and habitat (pelagic/demersal). Concentrations measured in the present study are below European guidelines for human consumption of fishes and prawns. However, industrial‐use contaminants should be monitored in developing countries because they are contaminants of emerging concern as a result of increasing industrialization and global trade of used products and wastes. Environ Toxicol Chem 2022;41:321–333. © 2021 The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals LLC on behalf of SETAC