Effects of nickel oxide nanoparticles on survival, reproduction, and oxidative stress biomarkers in the marine calanoid copepod Centropages ponticus under short-term exposure.

Excessive use of nickel oxide nanoparticles (NiO NPs) in various industrial and commercial products can lead to various negative effects in human and environmental health due to their possible discharge into the environment. Nerveless, information about their ecotoxicological effects on marine organisms are lacking. Copepods are good ecotoxicological models because of their high sensitivity to environmental stress and their key role in the marine food webs. In this study, 48 h acute tests were conducted on the marine planktonic copepod Centropages ponticus to assess lethal and sublethal toxicities of NiO NPs. The results revealed LC50 (48 h) of 4 mg/L for adult females. Aggregation and settling of NiO NPs were observed at concentrations ≥ 2 mg/L. Exposure to sublethal concentrations (≥ 0.02 mg/L for 48 h) had significant negative effects on reproductive success in C. ponticus. Egg production after 24 h and 48 h decreased by 32% and 46%, respectively at 0.02 mg/L and 70% and 82%, respectively, at 2 mg/L. Hatching success was reduced by 70% and 79% at 2 mg/L for eggs produced after 24 h and 48 h respectively. Antioxidant enzymatic activity increased significantly with NiO NP concentration and time, indicating that NiO NPs can cause oxidative stress in C. ponticus even under short-term exposure, while significant inhibition of acetylcholinesterase activity at 2 mg/L after 48 h suggests neurotoxic effects of NiO NPs.

Polychlorinated biphenyls, polybrominated diphenyl ethers, and phthalates in roach from the Seine River basin (France): impact of densely urbanized areas.

Endocrine disruptors (EDs) from three chemical classes-polychlorinated biphenyls (PCBs), polybrominated diphenyl ethers (PBDEs), and phthalates-were investigated in the Seine River and one tributary, the Orge River, upstream and downstream of urban areas. The impact of urban areas was characterized by a concentration increase of all compounds in the Seine River and for phthalates and PBDEs in the Orge River. In the Seine River, from upstream (Marnay) to downstream (Triel) of urban areas, water concentration increases were greater for diethylhexyl phthalate (DEHP) (6 times, p < 0.05) and ∑tri-hexa BDE (5 times [p < 0.05]) than for ∑7PCBi (2.6 times). Simultaneously, sediments displayed a strong accumulation of contaminants downstream and compared with upstream values, their concentrations increased greatly: 202-fold for DEHP, 69-fold for BDE209, 25-fold for ∑tri-hexa-BDE, and 11-fold for ∑7PCBi. Variations of fish ED concentrations gave an indication of their habitat contamination increase observed downstream of densely urbanized areas of the Seine River, especially for PBDEs (∑tri-hexa-PBDEs = 14-fold increase ≤15.7 ± 6.9 ng g(-1) dry weight [dw; p < 0.001]) and for PCBs (∑7PCBi eightfold increase ≤211 ± 55 ng g(-1) dw [p < 0.01]). PCA results highlighted relationships between the different ED classes. A correlation (p < 0.05) was observed between PCB and PBDE fish concentrations, suggesting common sources and similar absorption mechanisms. For PCBs, which were poorly biodegraded, the bioaccumulation factor was strongly correlated (p < 0.001) to molecular hydrophobicity, whereas for PBDEs a negative correlation (p < 0.05) was observed related active debromination processes. This multichemical study investigates for the first time the occurrence of a wide range of EDs in roach, which was chosen as a sentinel species for this survey of surface water contamination.

Bioaccumulation of polybrominated diphenyl ethers by the freshwater benthic amphipod Gammarus pulex.

This study reports on the relationship between polybrominated diphenyl ether (PBDE) levels in water, sediment, and the benthic macroinvertebrate Gammarus pulex, which plays a major ecological role in freshwater ecosystems. Samples were taken in a periurban watershed (near Paris, France), and PBDEs were systematically detected in sediment (≤727 ng g(-1) OC) and G. pulex (≤264 ng g(-1) lipids). PBDEs were also occasionally detected in the water column at low levels (∑ PBDEs < 1.5 ng L(-1)). The log values of bioaccumulation factors were in the range 7.8 ± 0.1-8.3 ± 0.4 L kg(-1) for tetra- and penta-BDEs, which were the only ones quantified in the dissolved phase of river water. Meanwhile, levels of individual tri- to hepta-PBDE congeners in G. pulex generally positively correlated with sediment levels, suggesting an equilibrium situation. Biota-to-sediment accumulation factors (BSAFs) of tri-hepta BDEs were congener specific and were in the range 0.5 ± 0.3-2.6 ± 1.2. For several PBDEs, BSAF values deviated from the expected range, likely because of in vivo metabolism.

Occurrence of polybrominated diphenyl ethers, polychlorinated biphenyls, and phthalates in freshwater fish from the Orge river (Ile-de France).

Polybrominated diphenyl ethers (PBDEs), polychlorinated biphenyls (PCBs), and phthalates were investigated from July 2009 to April 2010 in three fish species from the Orge river, which flows in a densely populated area of Ile-de-France. In two Cyprinidae (roach and chub) and one Percidae (perch), muscle contents in increasing order ranged as follows: 12-18 ng g(-1) dw for PBDEs (Σtri-hepta), 120-170 ng g(-1) dw for PCBs (Σ7), and 2,250-5,125 ng g(-1) dw for phthalates (Σ7). No variation was observed between contaminant contents and lipid levels. No biomagnification was found according to the trophic level for PBDEs and PCBs, whereas for phthalates the highest contents were found in perch. Seasonal variations were observed with the lowest PBDE and PCB contents occurring in July after spawning in roach and perch (p < 0.001). PBDE content followed a decreasing trend-gonad > liver > muscle-whatever the period. For PCBs, gonad and liver contents remained greater than that of muscle (p < 0.05). Our results indicate a preferential accumulation of halogenated compounds in gonad and liver outside the reproduction period. Bioaccumulation factors for PCBs in muscle were significantly correlated to their chlorination degree in perch (p < 0.01) and roach (p < 0.01). In roach, that correlation slope was by decreasing importance order as follows: gonad > liver > muscle. The biota-sediment accumulation factors varied from 0.1 to 29.2, from 1.6 to 4.8, and from 1 to 123.5 for PBDEs, PCBs, and phthalates, respectively. These results contribute to document the use of freshwater fish as bioindicators of river quality.

Influence of hydrological parameters on organohalogenated micropollutant (polybrominated diphenyl ethers and polychlorinated biphenyls) behaviour in the Seine (France).

The temporal dynamics of polybrominated diphenyl ethers (PBDEs) and polychlorinated biphenyls (PCBs) were investigated in a heavily urbanized river (Seine River, Paris, France) from November 2009 to May 2010. Pollutant concentrations were in the range of 0.2 to 3.8 ng l(-1) (median 1.1) and 0.4 to 3.6 ng l(-1) (median 1.1) for ∑ tri-deca BDEs and ∑ 7PCBs, respectively. In addition, for both PBDEs and PCBs, the partitioning between the particulate and dissolved phases was investigated. Due to their low water solubility, PBDEs were mainly (>70%) bound to particles. In contrast, only 54% of ∑ 7PCBs occurred in the particulate phase, and their partitioning was influenced by the degree of chlorination. During the sampling period, PBDE/PCB fluxes were quite similar and ranged from 3 to 128 and from 6 to 125 g day(-1), respectively. The annual mass flow of PBDEs and PCBs was estimated to 10 kg for both. Contrary to PCBs and BDE-209, the temporal evolution of ∑ tri-hepta BDEs was related to particulate organic matter content, which is controlled by river flow variations. This suggests that they exhibit different sources or behavior in the Seine River.

Development of analytical procedures for trace-level determination of polybrominated diphenyl ethers and tetrabromobisphenol A in river water and sediment.

The aim of this work was to develop procedures for the simultaneous determination of selected brominated flame retardants (BFRs) in river water and in river bed sediment. The target analytes were polybrominated diphenyl ethers (PBDEs) and tetrabromobisphenol A (TBBPA). To determine dissolved BFRs, a novel mixed-mode solid-phase extraction procedure was developed by combining a hydrophobic sorbent (C(18)) with a silica-based anion exchange sorbent, so as to overcome the negative artefact induced by dissolved organic carbon. Extraction recoveries exceeded 73% for most analytes, except for BDE-183 and BDE-209 (57%). As regards suspended sediment and river bed sediment, extraction was carried out by means of ultrasonication (recoveries: 73-94%). These procedures, combined to gas chromatography coupled to negative chemical ionisation mass spectrometry (GC-NCI-MS), enabled the determination of BFRs at trace level: 3-160 pg L(-1) in river water, 5-145 pg g(-1) in bed sediment. These methods were applied to the determination of PBDEs and TBBPA in a suburban river (near Paris, France). PBDEs were systematically detected in the water column (SigmaBDEs, 2,300-4,300 pg L(-1)); they partitioned between the dissolved and particulate phases and BDE-209 was the dominant congener, followed by BDE-99 and BDE-47. TBBPA was detected in the dissolved phase only (<35-68 pg L(-1)). All selected BFRs were ubiquitous in bed sediments and levels ranged from 3,100 to 15,100 pg g(-1) and from 70 to 280 pg g(-1) (dry weight), for SigmaBDEs and TBBPA, respectively.