The effect of titanium dioxide nanoparticles on neuroinflammation response in rat brain

Titanium dioxide nanoparticles (TiO₂ NPs) are widely used for their whiteness and opacity in several applications such as food colorants, drug additives, biomedical ceramic, and implanted biomaterials. Research on the neurobiological response to orally administered TiO₂ NPs is still limited. In our study, we investigate the effects of anatase TiO₂ NPs on the brain of Wistar rats after oral intake. After daily intragastric administration of anatase TiO₂ NPs (5–10 nm) at 0, 50, 100, and 200 mg/kg body weight (BW) for 60 days, the coefficient of the brain, acethylcholinesterase (AChE) activities, the level of interleukin 6 (IL-6), and the expression of glial fibrillary acidic protein (GFAP) were assessed to quantify the brain damage. The results showed that high-dose anatase TiO₂ NPs could induce a downregulated level of AChE activities and showed an increase in plasmatic IL-6 level as compared to the control group accompanied by a dose-dependent decrease inter-doses, associated to an increase in the cerebral IL-6 level as a response to a local inflammation in brain. Furthermore, we observed elevated levels of immunoreactivity to GFAP in rat cerebral cortex. We concluded that oral intake of anatase TiO₂ NPs can induce neuroinflammation and could be neurotoxic and hazardous to health.     

Effect of physiological conditions and biochemical factors of mussels Mytilus galloprovincialis in radioactivity monitoring programs along the Algerian coast

Environmental Science and Pollution Research - A study was carried out to determine the activities of radionuclides (137Cs, 40K, 226Ra, 214Bi, 214Pb, and 210Pb) and the levels of biochemical...     

A Comparative Study of Doum fiber and Shrimp Chitin Based Reinforced Low Density Polyethylene Biocomposites

The aim of this paper was to study the effects of reinforcing low density polyethylene (LDPE) by using bio-fillers (Doum cellulose or Shrimp chitin) on the mechanical properties. Both, Doum cellulose extracted frsom Doum leaves and Shrimp chitin extracted from shrimp co-products were compounded with LPDE without and with compatibilizer. The biocomposites were prepared by melt blending in a twin-screw extruder. Torsion and flexural tests were performed to investigate the impact of each reinforcement on the biocomposite mechanical properties. The SEM was carried out to study the filler/polymer interface adhesion. The present study has demonstrated that Doum fibers and shrimp chitin succeed in improving the mechanical properties of LPDE bio-composites. The results also showed that the use of maleic anhydride-grafted polyethylene as a compatibilizer improves filler adhesion/matrix and mechanical properties. This study exhibits that polyethylene composites based on Doum fibers or shrimp chitin can be used to replace the polyethylene materials in several fields like packaging and automotive industries.     

Suitability for human consumption and agriculture purposes of Sminja aquifer groundwater in Zaghouan (north-east of Tunisia) using GIS and geochemistry techniques

In Tunisia, the water resources are limited, partially renewable and unequally distributed between the wet north and the dry south of the country. The Sminja aquifer in Zaghouan city is located in north-east of Tunisia, between latitudes 36°38′ and 36°47′ and longitudes 9°95′ and 10°12′. This aquifer is used to satisfy the population needs for their domestic purposes and agricultural activities. Water analyses results are expressed by many methods, among which are geochemical methods combined with the geographic information system (GIS) (all schematic presentations of the diagram software (Piper, Riverside, Wilcox…), which can be used to assess the suitability of the Sminja aquifer groundwater for human consumption and irrigation purposes. A total of 23 wells were sampled in January 2013, and the concentrations of major cations (Na⁺, Ca²⁺, Mg²⁺ and K⁺), major anions (Cl^?, SO₄ ^2? and HCO₃ ^?), electrical conductivity and total dissolved solids were analysed. In the Sminja groundwater, the order of the cations dominance was Na > Ca > Mg > K and that of the anions was Cl > HCO₃ > SO₄. All of the analysed samples of the study area exceed chemical values recommended by the World Health Organisation guidelines and Tunisian Standards (NT.09.14) for potability but with different percentages. The aquifer spatial distribution of saturation indices reveals that all groundwater samples are under-saturated with gypsum, halite and anhydrite and are over-saturated with respect to calcite and dolomite based on water quality evaluation parameters for irrigation purposes; here, 87 % of samples in Sminja aquifer groundwater are suitable, whereas 13 % are unsuitable for irrigation uses.     

PBDEs and PCBs in the liver of the St Lawrence Estuary beluga (Delphinapterus leucas): a comparison of levels and temporal trends with the blubber

Due to their lipophilic properties, persistent organic pollutants (POPs) are commonly assessed using the blubber of marine mammals. However, these chemicals are also accumulating in other tissues including the liver. Some pollutants, namely perfluorinated alkyl acids, are found predominately in the liver and blood of marine mammals, and thus monitored in those tissues. This raises the question whether any tissue would represent an identical trend of POPs in the SLE beluga. The current study reports the first temporal trends of PBDEs and PCBs in the liver of 65 SLE belugas. Neither ∑?PBDEs nor major individual PBDE-homolog group concentrations showed significant trends between 1993 and 2007. Also, ∑??PCBs did not change over years, although, tetra-, penta- and hepta-PCB decreased by 7.1, 6.8 and 8.5%, respectively, in males, whereas tetra-, penta- and octa-PCBs declined by 11, 12 and 12.9%, respectively, in females. In order to compare the distribution of POPs between liver and blubber, a lipid normalised concentration ratio R (blubber/liver) for PBDEs and PCBs was calculated for each individual beluga. For all PBDE and several PCB homolog groups, mean R values were not statistically different from unity indicating that the partitioning of these POPs is governed by the tissue lipid-content. Temporal trends of R ratios of PBDEs and PCBs were also examined. There were generally no significant temporal trends except for PBDEs in males where R increased in average by 12.7 ± 2.9% yearly. The stratification of the blubber into a metabolically active (inner) and less active layers (outer blubber) may result in a slower response time of the blubber (full depth) than the liver to the recent change of contamination in the environment and explain the time trend differences between both tissues. This study suggests that the liver is more representative of recent exposure to lipophilic contaminants.     

Quinoa value chain,adoption, and market assessment in Morocco

Environmental Science and Pollution Research - Agriculture faces many challenges such as climate change, droughts, and salinity, which requires urgent interventions for fast adaptation and...     

Biosorption of copper from aqueous solutions by date stones and palm-trees waste

The removal of toxic metals from wastewaters by biosorption, based on the metal-binding capacities of various biological materials, has received much interest. However, the success of this approach depends on economic feasibility, which can be obtained by optimization of the environmental conditions. This paper evaluates, for the first time, the use of low-cost biosorbent (date stones (DS) and palm-tree waste (PTW)) to eliminate Cu(II) from aqueous solutions. The effect of some parameters on copper biosorption has been studied using date stones and palm-tree waste as solid sorbents. Results show that the highest percentage of copper adsorption was obtained for the smallest size of the sorbent particles. The biosorption process was found to occur rapidly, i.e. the maximum sorption capacity was reached within 20 min. The process involved pseudo-second-order kinetics with an activation energy value within the normal range considered for processes, where a physical interaction between the sorbate and the sorbent solid predominated. The thermodynamic parameters of the copper ions uptake onto the solid sorbents indicated that, the process was endothermic and proceeds spontaneously from the date stones. However, the thermodynamic studies of the adsorption of copper on palm-tree waste indicated that the process was exothermic and proceeds spontaneously.     

Ecotoxicological impact assessment of the brine discharges from a desalination plant in the marine waters of the Algerian west coast,using a multibiomarker approach in a limpet,Patella rustica

The aim of our study is to evaluate the impact of Bousfer desalination plant brine discharges on the Algerian west coast, on a natural population of the marine gastropod mollusc Patella rustica. The effects of a chronic exposure to such discharges are complex to understand due to the combined effects of environmental physico-chemical parameters (e.g., high salinity) and different pollutants that can modulate the physiological responses of this species to stress. In this context, we assessed the biological effects in a marine species P. rustica, by a multibiomarker approach that provided information on the health status of organisms in response to such an environmental stress. We measured biomarkers in the whole soft tissues of limpets as indicators of neurotoxicity (AChE activity), oxidative stress (CAT, SOD, GR, and GPx activities), biotransformation (GST), oxidative damage (LPO through TBARS levels), and genotoxicity (CSP 3-like activity). In parallel, hydrological parameters were measured in the Bay of Oran, at four selected sites: site H considered as a “hotspot,” located at Bousfer desalination plant; two other sites E and W, at the east and the west of H respectively; finally, site R “reference” located in Madragh, which is considered as a remote clean site. Our analyses revealed that the activities of antioxidant defense enzymes reached the highest levels in P. rustica collected from site H. The activation of antioxidant defense system in these organisms translated the alteration of their status health, reflecting a level of environmental disruption generated by the desalination plant brine discharges and the high salinity in this area. We also observed that the tissues of limpets collected from site H as well as the two other sites, E and W, had undergone molecular damage, confirmed by the high levels of CSP 3-like activity. This damage resulted from chronic exposure to environmental conditions, potentially genotoxic, due to the desalination plant discharges. The present results indicate the adverse impact of brine effluents from desalination plants on marine fauna and suggest the need for a more consistent approach to environmental management of brine discharges.

     

Heat shock protein 47 stress responses in Chinese hamster ovary cells exposed to raw and reclaimed wastewater

As wastewater reclamation and reuse becomes more widespread, risks of exposure to treated wastewater increase. Moreover, an unlimited number of pollutants can be identified in wastewater. Therefore, comprehensive toxicity assessment of treated wastewater is imperative. The objective of this study was to perform a comprehensive toxicity assessment of wastewater treatment systems using stress response bioassays. This powerful tool can comprehensively assess the toxicity of contaminants. In this study, samples from conventional activated sludge treatment, membrane bioreactors (MBRs) with different pore sizes and sludge retention times (SRTs), rapid sand filtration, coagulation, nano-filtration (NF) and reverse osmosis (RO) were investigated. The results of stress response bioassays confirmed that the secondary effluent showed higher stress response than influent indicating that biological treatment generates toxic compounds. The results obtained from molecular weight fractionation of water samples demonstrated that organic matter with a higher molecular weight fraction (>0.1 μm) causes toxicity in secondary effluent. Furthermore, supernatant from MBR reactors showed toxicity regardless of SRT. On the other hand, stress response was not detected in MBR permeates except for an MBR equipped with a larger pore size membrane (0.4 μm) and with a short SRT (12 days). While rapid sand filtration could not remove the toxic compounds found in secondary effluent, coagulation tests, operated at an appropriate pH, were effective for reducing stress response in the secondary effluent. Experimental findings also showed that stress response was not detected in cases of NF and RO permeate subsequent to MBR treatment.