Environmental Science and Pollution Research - Over-application of fertilizers could not improve crop yield and agronomic efficiency, but result in increasing nitrogen (N) surplus and adverse... 相似文献
Environmental Science and Pollution Research - Depletion of natural resources and population aging are the two most critical challenges for environmental sustainability. However, the research that... 相似文献
Petroleum and derivatives have been considered one of the main environmental contaminants. Among petroleum derivatives, the volatile organic compounds benzene, toluene, ethylbenzene and xylene (BTEX) represent a major concern due to their toxicity and easy accumulation in groundwater. Biodegradation methods seem to be suitable tools for the clean-up of BTEX contaminants from groundwater. Genotoxic and mutagenic potential of BTEX prior and after biodegradation process was evaluated through analyses of chromosomal aberrations and MN test in meristematic and F1 root cells using the Allium cepa test system. Seeds of A. cepa were germinated into five concentrations of BTEX, non-biodegraded and biodegraded, in ultra-pure water (negative control), in MMS 4 × 10−4 M (positive control) and in culture medium used in the biodegradation (blank biodegradation control). Results showed a significant frequency of both chromosomal and nuclear aberrations. The micronucleus (MN) frequency in meristematic cells was significant for most of tested samples. However, MN was not present in significant levels in the F1 cells, suggesting that there was no permanent damage for the meristematic cell. The BTEX effects were significantly reduced in the biodegraded samples when compared to the respective non-biodegraded concentrations. Therefore, in this study, the biodegradation process showed to be a reliable and effective alternative to treat BTEX-contaminated waters. Based on our results and available data, the BTEX toxicity could also be related to a synergistic effect of its compounds. 相似文献
Inhaca Island, southern Mozambique, is located towards the southerly latitudinal limits of coral reef growth. Reef development is restricted to the margins of channels which dissect intertidal flats on the Maputo Bay side of the island, and to depths of around 6 m. In contrast to lower latitude reefs, reef development is therefore both spatially and bathymetrically restricted (largely due to high turbidity levels). These natural stress levels were exacerbated, via increased freshwater and sediment discharge, during the severe floods of late 1999/early 2000. Flood impacts varied but were most significant on reefs on the inner (western) side of the island where live coral cover (LCC) decreased from 60.5% (1999) to 24.0% (2001). This is attributed to freshwater-induced bleaching. Dead in situ coral cover increased from 18.6% (1999) to 51.3% (2001). Reefs on the southern tip of the island, by contrast, were relatively unaffected. It is suggested that this largely reflects a closer proximity to the open Indian Ocean which mitigated the effects of freshwater dilution. 相似文献
Radiation with UV-B increased the damage to DNA in Scytonema javanicum, a desert-dwelling soil microorganism, and the level of damage varied with the intensity of UV-B radiation and duration of exposure. Production of reactive oxygen species (ROS) also increased because of the radiation. Different exogenous chemicals (ascorbate acid, ASC; N-acetylcysteine, NAC; glyphosate, GPS; and 2-methyl-4-chlorophenoxyacetic acid, MCPA-Na) differed in their effect on the extent of DNA damage and ROS production: whereas NAC and ASC protected the DNA from damage and resulted in reduced ROS production, the herbicides (GPS and MCPA-Na) increased the extent of damage, lowered the rate of photosynthesis, and differed in their effect on ROS production. The chemicals probably have different mechanisms to exercise their effects: NAC and ASC probably function as antioxidant agents or as precursors of other antioxidant molecules that protect the DNA and photosynthetic apparatus directly from the ROS produced as a result of UV-B radiation, and GPS and MCPA-Na probably disrupt the normal metabolism in S. javanicum to induce the leaking of ROS into the photosynthetic electron transfer pathway following UV-B radiation, and thereby damage the DNA. Such mechanisms have serious implications for the use of environment-friendly herbicides, which, because they can destroy DNA, may prove harmful to soil microorganisms. 相似文献
The white shrimp, Litopenaeus vannamei, a globally important cultured prawn species, is an ideal animal for studying the impairment caused by the effects of heavy metals that are often detected in coastal areas. In this study, L. vannamei was exposed to different concentrations of cadmium (Cd) and zinc (Zn) for up to 28 d. Histopathological alterations in the hepatopancreas were observed in L. vannamei after long-term exposure to Cd and Zn. Hepatopancreatic injury was further confirmed by the inductions of two biochemical markers, hemolymphatic glutamate-oxalacetate transaminase (GOT) and glutamate-pyruvate transaminase (GPT). It was notable that L. vannamei was able to repair its hepatopancreas from the damage caused by Zn, which was evidenced by the results of the histopathological observations, determinations of tissue metal concentrations, and examination of GOT and GPT levels. 相似文献
The results of this study provide a measure of the levels of dioxin-like compounds (polychlorinated dibenzo-p-dioxins, polychlorinated dibenzofurans and polychlorinated biphenyls) in pooled blood serum collected throughout Australia in 2003. De-identified samples selected from surplus pathology samples were stratified on the basis of gender, region and age. In total 9090 samples were collected and analysed as 96 pools. Dioxin-like chemicals were detected in all strata. The mean and median levels expressed as TEQ values for all pooled samples were 10.9+/-1.0 pg TEQ g(-1) lipid and 8.3 pg TEQ g(-1) lipid. For males and females the mean levels were 10.4+/-0.6 pg TEQ g(-1) lipid and 11.5+/-1.5 pg TEQ g(-1) lipid, respectively. A direct relationship of increasing dioxin-like chemical levels with increasing age was observed and could be described by the following equation: Levels in blood expressed as pg TEQ g(-1) lipid = 3.3 exp(0.0251 age) (r2 = 0.87). No significant differences were observed in the levels of dioxin-like chemicals in samples collected from males and females. In addition, the levels of dioxin-like chemicals across the five regions were similar within each age range. In summary, the levels of dioxin-like chemicals in the Australian population are low compared to international levels and are similar across all regions of Australia within each designated age range. The levels of these chemicals increase with age and can be estimated if the age of an individual is known. 相似文献
Electrocoagulation (EC) is an excellent and promising technology in wastewater treatment, as it combines the benefits of coagulation, flotation, and electrochemistry. During the last decade, extensive researches have focused on removal of emerging contaminants by using electrocoagualtion, due to its several advantages like compactness, cost-effectiveness, efficiency, low sludge production, and eco-friendness. Emerging contaminants (ECs) are micropollutants found in trace amounts that discharging into conventional wastewater treatment (WWT) plants entering surface waters and imposing a high threat to human and aquatic life. Various studies reveal that about 90% of emerging contaminants are disposed unscientifically into water bodies, creating problems to public health and environment. The studies on removal of emerging contaminants from wastewater are by global researchers are critically reviewed. The core findings proved that still more research required into optimization of parameters, system design, and economic feasibility to explore the potential of EC combined systems. This review has introduced an innovative collection of current knowledge on electro-coagulation for the removal of emerging contaminants.
Low-density polyethylene (LDPE), biaxially oriented polypropylene (BOPP), and expanded polystyrene (EXPS) are the most common plastics found in every home of the world, but only ~ 10% enter the recycling chains. Consequently, the study of plastic biodegradation by microorganisms and insects, such as the wax moths, has gained special interest. Galleria mellonella (L.) has been shown to consume single-layered polyethylene and polystyrene, though biological impacts of this consumption have been rarely reported. We evaluated the consumption of different plastics by G. mellonella larvae (L7, mean size: 25–30 mm) and its effect on larval duration, survival, and development. For this, we offered the larvae five diets: single-layered LDPE, EXPS, BOPP, triple-layered polyethylene (SB, for silo-bags), and a control with beeswax. We recorded the state and weight of the materials and the state of larvae until they reached the adult stage. Larvae consumed more PE (both LDPE and SB) and EXPS than BOPP; still, they were able to emerge as adults in all treatments. Larvae that consumed plastics turned into pupal stage faster than those that consumed beeswax, regardless of the type and amount of plastic consumed. This is the first report of wild G. mellonella larvae in Argentina consuming biaxially polypropylene and silo-bags.
We have isolated and characterised a novel aerobic bacterial strain, designated MS3-02, belonging to the genus Janibacter sp. The capability of this new strain to degrade polychlorinated biphenyls (PCBs) in a commercial mixture (Aroclor 1242) in liquid medium and in soil (sterile and non sterile soil), under laboratory scale, has been evaluated. MS3-02 was isolated from the soil around of an incinerator, located in the east of Madrid (Spain). Gas-chromatographic analysis showed that MS3-02 was able to reduce most peaks observed in the chromatogram between 70% and 100% after seven days of incubation in a culture mineral medium containing yeast extract, but without the addition of biphenyl. The presence of biphenyl in the culture medium decreased the rate of PCB degradation by this bacterium. Comparing the performance of the MS3-02 in liquid culture medium and in soil, degradation was less efficient in sterile soil and still less efficient in non sterile soil. Under the best conditions (sterile soil and 20 weeks of incubation) MS3-02 was able to reduce, between 50% and 100%, nine of the main gas-chromatographic peaks in Aroclor 1242. 相似文献
Environmental building recommendations aimed towards new environmental policies and management-changing decisions which as example demonstrated in consideration of the problems of Canadian oil sands operators. For the implementation of the circular economic strategy, we use an in-depth analysis of reported environmental after-consequence on all stages of the production process. The study addressed the promotion of innovative solutions for greenhouse gas emission, waste mitigation, and risk of falling in oil prices for operators of oil sands with creating market opportunities. They include the addition of microalgae biomass in tailings ponds for improvement of the microbial balance for the water speedily cleaning, recycling, and reusing with mitigation of GHG emissions. The use of food scraps for the nutrition of microalgae will reduce greenhouse gas emission minimally, on 0.33 MtCO2eq for Alberta and 2.63 MtCO2eq/year for Canada. Microalgae-derived biofuel can reduce this emission for Alberta on 11.9–17.9 MtCO2eq and for Canada on 71–106 MtCO2eq/year, and the manufacturing of other products will adsorb up to 135.6 MtCO2 and produce 99.2 MtO2. The development of the Live Conserve Industry and principal step from non-efficient protection of the environment to its cultivation in a large scale with mitigation of GHG emission and waste as well as generating of O2 and value-added products by the use of microalgae opens an important shift towards a new design and building of a biological system. 相似文献
This work analyzes the influence of environmental and physiological parameters on PAHs accumulation in cultured mussels. Lipid content and reproductive stage are directly related with PAHs accumulation pattern. We observed a rapid accumulation and depuration of PAHs, mainly during periods of nutrients accumulation, spawns and gonadic restorations. Correlations between PAHs accumulation and physiological status indicate when mussels are more susceptible to adverse effects of these pollutants. A positive correlation between mutagenic congener’s accumulation and occurrence of gonadic neoplastic disorders is shown for the first time in mussels. Molecular indices were used to identify the origin of hydrocarbons accumulated by Mytilus, showing a chronic pyrolytic pollution and pollutant episodes by petrogenic sources and biomass combustion in the studied area. Multivariate analysis suggests the possibility of including physiological parameters of sentinel organisms in environmental biomonitoring programs, mainly in aquaculture areas, taking into account their two aspects: farms productivity and human food safety. 相似文献
Environmental Science and Pollution Research - This work deals with the theoretical approach of biodegradability, lipophilicity, and physiological activity of VAL and four degradation products... 相似文献
Fires are becoming more violent and frequent resulting in major economic losses and long-lasting effects on communities and ecosystems; thus, efficient fire monitoring is becoming a necessity. A novel triple multi-sensor approach was developed for monitoring and studying the burning of dry forest fuel in an open field scheduled experiment; chemical, optical, and acoustical sensors were combined to record the fire spread. The results of this integrated field campaign for real-time monitoring of the fire event are presented and discussed. Chemical analysis, despite its limitations, corresponded to the burning process with a minor time delay. Nevertheless, the evolution profile of CO2, CO, NO, and O2 were detected and monitored. The chemical monitoring of smoke components enabled the observing of the different fire phases (flaming, smoldering) based on the emissions identified in each phase. The analysis of fire acoustical signals presented accurate and timely response to the fire event. In the same content, the use of a thermographic camera, for monitoring the biomass burning, was also considerable (both profiles of the intensities of average gray and red component greater than 230) and presented similar promising potentials to audio results. Further work is needed towards integrating sensors signals for automation purposes leading to potential applications in real situations. 相似文献
Human serum samples (n?=?113) from Bizerte, northern Tunisia, collected between 2011 and 2012 were analyzed for 8 organochlorine pesticides (OCPs) including p,p′-dichlorodiphenyltrichloroethane (DDT) and its metabolites, hexachlorobenzene (HCB), hexachlorocyclohexane isomers, dieldrin, and heptachlor and 12 polychlorinated biphenyls (PCBs) congeners. Concentrations of these residues in serum were determined by gas chromatography with electron capture detector and total cholesterol (CHOL) and triglycerides (TG) levels were evaluated by enzymatic colorimetric method. HCB, p,p′-DDE, PCB-138, PCB-153, and PCB-180, were the most abundant organochlorine compounds (OCs) detected in >95 % of the study subjects. The mean levels of p,p′-DDE and HCB in serum were 168.8 and 49.1 ng?g?1 lipid, respectively. The sum PCBs concentrations ranged from 37.5 to 284.6 ng?g?1 lipid in the samples, with mean and median value of 136.1 and 123.2 ng?g?1 lipid, respectively. The PCB profile consisted of persistent congeners, such as PCB-138, PCB-153, and PCB-180 which contributed for approximately 82.7 % to the ∑PCBs. Statistical analysis showed that most OCs correlated significantly with age, considering all samples together or with gender differentiation. The present study shows that the levels of p,p′-DDE and ∑DDTs were significantly higher in females than in males (p?<?0.05), while PCBs levels were significantly higher in male (p?<?0.05) than in females. No statistically significant association was found between body mass index and concentration of any organochlorine pesticide or PCB congeners 153, 138, 180, or ∑PCBs. 相似文献