Development of novel and ecological keratin/cellulose-based composites for absorption of oils and organic solvents

Environmental Science and Pollution Research - Keratin/cellulose cryogels were successfully fabricated using chicken feathers (CF) and cardboard (C) from environmental waste for the first time, to...     

Metals in marine environment (mollusc Patella sp., fish Labrus bergylta, crustacean Cancer pagurus, beach sand) in a nuclear area, the North Cotentin (France)

The results of a 1-year long survey of trace metals concentrations (Al, Cd, Cr, Co, Cu, Fe, Mn, Hg, Ni, Pb, Zn) measured in beach sand, limpets and, occasionally, in fish and shellfish from the North Cotentin area (France), where nuclear industries are implanted, are presented. The objective of these study was to provide useful data for the validation of models predicting the impact of these industries on the marine environment. Even if differences were noted between sites for various metals, the levels are consistent with existing data published for similar site and do not appear to give evidence of contamination by industrial sites.     

Polybrominated diphenyl ethers (PBDEs) in mussels from selected French coastal sites: 1981-2003

The present study focused on the retrospective analysis of PBDEs in archived blue mussel (Mytilus edulis or Mytilus galloprovincialis) samples collected over the past 22 years (1981-2003) from coastal areas of France. We have found that PBDE levels in mussels from the English Channel increased markedly from 1981 to 1991-1995, doubling approximately every 5-6 years followed by a levelling off and a possible beginning of a decrease. The rate of the decline of hexa- and hepta-BDE congeners was more rapid than the decline of tetra- and penta-BDEs in these mussel samples. The difference in the course of time of lower and higher brominated PBDE concentrations suggests that the congener profile in the mussel samples changes over time. The increase in PBDE concentrations in the mussel samples contrasts with a concomitant constant decrease of chlorobiphenyls (CBs) in the same set of samples. However, pulse inputs of both groups of organohalogen compounds were determined for the mussel samples collected at the mouth of the Seine estuary and were probably related to riverine inundations and a flushing out of the deposited sediments from the internal estuary into the bay of the River Seine, as well as considerable dredging activities taking place during same years. In France, the highest PBDE concentrations were determined in the mussels from the English Channel, more precisely in the bay of the Seine, and the regional differences in PBDE levels were mainly connected to the difference in anthropogenic urban and industrial environmental pressures. Published data comparing PBDE levels in mussels have shown significant differences in concentrations between North/South America and Europe. This observation further confirms that the PBDE levels in the North American environment are higher than in Europe. However, the data used for this comparison of mussel contamination by PBDEs is still relatively sparse.     

Analysis of global and local population stratification of finless porpoises <Emphasis Type="Italic">Neophocaena phocaenoides</Emphasis> in Chinese waters

The existence of three distinct populations is widely accepted for the finless porpoise (Neophocaena phocaenoides) in Chinese waters: the Yellow Sea, Yangtze River, and South China Sea populations. Here, we use nine species-specific microsatellite loci, the complete mitochondrial DNA control region (912 bp), and the complete mitochondrial cytochrome b gene (1,140 bp) to further investigate potential population stratification in the Yellow Sea using 147 finless porpoise samples from the Bohai Sea and adjacent northern Yellow Sea, two regions that were largely underrepresented in previous genetic studies. Our F-statistics analyses confirm the previously described three populations, but further demonstrate significant genetic differentiation between the [Bohai + northern Yellow] Sea and the southern Yellow Sea. On the other hand, median-joining network analyses do not exhibit well-differentiated haplotype groups among different geographic populations, suggesting the existence of shared ancestral haplotypes. Levels of microsatellite diversity are moderate to high (mean H _E = 0.794) among the 147 [Bohai + northern Yellow] Sea finless porpoises and no recent bottleneck was detected, whereas mtDNA control region and cytochrome b gene diversity is low to moderate. The microsatellite genotypic and mtDNA haplotypic data also confirm the presence of mother-calf pairs in single-net bycatch cases. The results presented here highlight the necessity to treat the [Bohai + northern Yellow] Sea population (highly impacted by anthropogenic threats) as a separate Management Unit.     

Enhanced phytoextraction of an agricultural Cr- and Pb-contaminated soil by bioaugmentation with siderophore-producing bacteria

Bioaugmentation-assisted phytoextraction may enhance the phytoextraction efficiency thanks to larger metal mobilization by microbial metabolites. Green fluorescent protein-tagged cells of Pseudomonas aeruginosa, Pseudomonas fluorescens or Ralstonia metallidurans, able to produce siderophores, were inoculated in an agricultural soil containing Cr (488 mg kg(-1)) and Pb (382 mg kg(-1)) and maize was cultivated. Bacteria were inoculated as free or immobilized cells in Ca-alginate beads, with skim milk in the aim at improving both the bacterial survival and the in situ siderophore production. Skim milk addition increased inoculated Pseudomonads concentration in soil. Soil inoculation with free cells of R. metallidurans supplied with skim milk increased Cr accumulation in maize shoots by a factor of 5.2 and inoculation with immobilized P. aeruginosa cells supplied with skim milk increased Cr and Pb uptake by maize shoots by a factor of 5.4 and 3.8, respectively. However total metal taken up by the whole plant decreases almost always with bioaugmentation. Translocation factor also increased with P. aeruginosa or R. metallidurans by a factor of 6 up to 7. Inoculated bacteria concentration in soil was correlated with metals in the exchangeable fraction. Cr and Pb concentrations in the exchangeable fraction were correlated with metal contents in shoots or roots. Our results suggest that bioaugmentation-assisted phytoextraction is a relevant method in the aim at increasing the phytoextraction rate which usually limits the use of phytoremediation technologies.     

Performance of bioaugmentation-assisted phytoextraction applied to metal contaminated soils: a review

Bioaugmentation-assisted phytoextraction is a promising method for the cleaning-up of soils contaminated by metals. Bacteria mainly Plant Growth Promoting Rhizobacteria (PGPR) and fungi mainly Arbuscular Mycorrhizal Fungi (AMF) associated with hyperaccumulating or non-hyperaccumulating plants were analyzed on the basis of a bioprocess engineering approach (concentration and amount of metals extracted by plants, translocation and bioconcentration factor, and plant biomass). In average bioaugmentation increased metals accumulated by shoots by a factor of about 2 (metal concentration) and 5 (amount) without any obvious differences between bacteria and fungi. To optimize this process, new relevant microorganism-plant associations and field scale experiments are needed along with a common methodology for the comparison of all experiments on the same basis. Recommendations were suggested concerning both the microbial-plant selection and the implementation of bioaugmentation to enhance the microbial survival. The use of microbial consortia associated with plant was discussed notably for multi-contaminated soils.     

Impact of dispersed fuel oil on cardiac mitochondrial function in polar cod Boreogadus saida

In this study, impact of dispersed oil on cardiac mitochondrial function was assessed in a key species of Arctic marine ecosystem, the polar cod Boreogadus saida. Mature polar cod were exposed during 48 h to dispersed oil (mechanically and chemically) and dispersants alone. The increase observed in ethoxyresorufin-O-deethylase activity and polycyclic aromatic hydrocarbon metabolites in bile indicated no difference in contamination level between fish exposed to chemical or mechanical dispersion of oil. Oil induced alterations of O₂ consumption of permeabilised cardiac fibres showing inhibitions of complexes I and IV of the respiratory chain. Oil did not induce any modification of mitochondrial proton leak. Dispersants did not induce alteration of mitochondrial activity and did not increase oil toxicity. These data suggest that oil exposure may limit the fitness of polar cod and consequently could lead to major disruption in the energy flow of polar ecosystem.     

Stress and recovery assessment during simulated microgravity: Effects of exercise during a long-term head-down tilt bed rest in women

The aim of this study was to determine the effects of a 60-day head-down tilt long-term bed rest (HDT) on stress and recovery in sixteen healthy female volunteers. Participants were randomly assigned to either an exercise group (Exe) that followed a training program combining resistive and aerobic exercises, or to a no-exercise control group (Ctl). Psychological states were assessed using the Rest-Q, a validated questionnaire based on stress–recovery responses. A longitudinal analysis revealed significant changes in the general and specific-stress scales for all participants throughout the experiment with a critical stage from supine to standing posture leading to a significant decrease in physical recovery. During HDT, Exe reported higher scores on stress subscales, as well as lower recovery scores compared to the Ctl. During the post-HDT ambulatory recovery period, the exercisers still reported higher scores than the non-exercisers on the Lack of energy stress-related scale, along with lower scores in general well-being and personal accomplishment. The present findings show that simulated weightlessness such as HDT may induce psychological stress and lead to subsequent alterations in perceived recovery. Exercise did not reduce HDT impaired effects on stress and recovery states. Several suggestions, including psychological preparation, are proposed to support the beneficial effects of exercise on psychological factors.