Can PBDE natural formation and degradation processes interfere with the identification of anthropogenic trends and sources? Evidences from sediments of the Nador Lagoon (Morocco)

Legacy Polybrominated Diphenyl Ethers (PBDEs) Trends in Top Predator Fish of the Laurentian Great Lakes (GL) from 1979 to 2016: Will Concentrations Continue to Decrease?

“…Therefore, it did not consider the potential bioaccumulation/biotransformation processes when PBDEs move through the food web. The depletion of the higher brominated congeners through the food web and enrichment of BDE-47 is consistent with debromination, and implies that both the commercial mixtures and biotransformed or debrominated PBDE may be important PBDE sources for lake trout. ,, …”

“…For example, PBDEs have been shown to be retained in furniture (8–10 years), electric appliances (9–18 years), electronics (5–10 yeas), sealants (5–20 years), and insulation materials (over 100 years) . These existing products can be important PBDE sources to the environment as PBDEs were not chemically bonded into these products so they can easily leach out. ,, Sediments are another PBDE reservoir that can continue to supply PBDEs into the GL aquatic ecosystem due to the high PBDE concentrations in GL sediment (10 2 –10 3 times higher than that in GL water). ,, Although the five major PBDE congeners found in fish contributed only 10% of the total mass of PBDE in GL sediment (BDE-209 is the dominant congener at about 90%), the higher brominated congeners can be degraded to lower brominated forms through multiple pathways including photocatalysis, , and biotransformation by microbes, , wetland plants, , and fish, ,, and thus, may continue to be a source of lower brominated congeners to the ecosystem. , …”

“…11,17,39 Sediments are another PBDE reservoir that can continue to supply PBDEs into the GL aquatic ecosystem due to the high PBDE concentrations in GL sediment (10 2 −10 3 times higher than that in GL water). 20,40,41 Although the five major PBDE congeners found in fish contributed only 10% of the total mass of PBDE in GL sediment (BDE-209 is the dominant congener at about 90%), 21 the higher brominated congeners can be degraded to lower brominated forms through multiple pathways including photocatalysis, 30,42 and biotransformation by microbes, 43,44 wetland plants, 15,29 and fish, 32,45,46 and thus, may continue to be a source of lower brominated congeners to the ecosystem. 36,45 The current study provides the most complete analysis (1979 to 2016) of the five-major legacy PBDE congeners (BDE-47, BDE-99, BDE-100, BDE-153, and BDE-154) in top predator fish (lake trout, Salvelinus namaycush and walleye, Sander vitreus) in the GL region.…”

Social-Environmental Analysis for the Management of Coastal Lagoons in North Africa

“…Nador lagoon in Morocco has several industrial activities, including mining and metallurgy, such as iron, pyrite, pyrrhotite, and chalcopyrite. The industrial effluent from the Selouane industrial zone is discharged into the lagoon during the wet season (Piazza et al, 2016).…”

“…Furthermore, there is industrial effluent coming from the Selouane industrial area that is discharged into the lagoon during the wet season. The pressures from industrial effluent (Nador lagoon) include inputs of pollutants, such as polychlorinated biphenyls (PCB), polycyclic aromatic hydrocarbons (Giuliani et al, 2015b), and increasing inputs of polybrominated diphenyl ethers (Piazza et al, 2016).…”