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Procaine penicillin alters swimming behaviour and physiological parameters of Daphnia magna
2019
Bownik, Adam | Ślaska, Brygida | Bochra, Justyna | Gumieniak, Katarzyna | Gałek, Kinga
Procaine penicillin (PP) is a β-lactam antibiotic widely used in human and veterinary medicine. Although PP is detected in surface water, little is known on its effects on aquatic invertebrates. Our aim was to determine the influence of PP on swimming behaviour (track density, swimming speed, turning angle, hopping frequency) and physiological activity (oxygen consumption, heart rate, thoracic limb movement) of a freshwater invertebrate Daphnia magna exposed to PP at concentrations of 11.79 mg/L, 117.9 mg/L and 1179 mg/L for 2 h and 24 h. The results showed no mortality; however, reduction of swimming activity manifested by the decreased track density, swimming speed and turning angle noted in Daphnia exposed to all the concentrations of PP. Increase of oxygen consumption was observed after 2-h exposure; however, decrease of this parameter was found after 24 h. PP also reduced heart rate and thoracic limb movement in a concentration-dependent manner. The results suggest that the antibiotic should not induce mortality; however, it may affect swimming behaviour and physiological parameters of Daphnia magna particularly inhabiting aquaculture facilities with intensive antibiotic treatment. On the basis of the present results, we also suggest higher sensitivity of behavioural and physiological parameters of cladocerans than the commonly used endpoints: mortality or immobilisation and their possible application as a part of early warning systems in monitoring of surface water toxicity.
Показать больше [+] Меньше [-]Application of selected life cycle occupational safety methods to the case of electricity production from pyro-oil
2019
Oguzcan, Semih | Tugnoli, Alessandro | Dvarioniene, Jolanta
Life cycle thinking is a necessary component in preventing the shifting of burden along the life cycle and from one impact category to another. For this reason, many have focused on integrating life cycle thinking into occupational risk assessment. The resultant methods have different properties in terms of scope and outcomes. Literature has been reviewed for life cycle occupational risk assessment methodologies, and 3 methods (life cycle inherent toxicity (LCIT) method, work environment characterization factors (WE-CFs) method, and life cycle risk assessment (LCRA) method) have been selected and applied in a case study of electricity production from pyro-oil to identify suitability and research gaps in the existing literature. The results of the LCIT method were highly heterogenous over life cycle of electricity production. For the current case, the major cancer and non-cancer impacts originated from the same life cycles. The results from WE-CFs method were highly heterogenous over the life cycle of electricity production as well. Agriculture contributed the most to the occupational risks. In the LCRA method, averaging caused the information about the frequency of the risks over life cycle to be lost. The method showed the well-known bargaining between accuracy and simplicity when complex systems are considered. Results from this method were quite homogenous among life cycles, due to the averaging effect. Detailed reporting and follow-up of the worker health issues can enable a more accurate application of the WE-CFs method. The overall results showed that it was possible to apply these 3 methodologies for the EU-28 region.
Показать больше [+] Меньше [-]The mediated role of complement C3 in PM2.5 exposure and type 2 diabetes mellitus: an elderly panel study in Beijing, China
2019
Tong, Yuanren | Bai, Lu | Luo, Kai | Zhao, Meiduo | Xu, Jing | Li, Ang | Li, Runkui | Yang, Mingan | Xu, Qun
Diabetes mellitus (DM) is a common chronic disease worldwide. Ambient air pollution has long been proven to be associated with type 2 diabetes mellitus (T2DM) progression, but the underlying mechanism is not clear yet. In addition, previous studies mainly focused on the prevention of healthy people against the incidence of T2DM. We designed a panel study including two follow-ups and enrolled 39 patients with T2DM living in Beijing. Linear mixed model was fitted to assess the association between two pairs of variables (ambient air pollution exposure and C3 levels, ambient air pollution exposures and T2DM index). Mediation analysis of C3 between ambient air pollution exposure and indicators of T2DM progression was conducted. We found that PM2.5 exposures is are negatively associated with serum complement C3. Given that C3 might act as a protector of pancreas β cell, PM2.5 exposures could accelerate disease in T2DM populations. No mediation effects were found. This study reveals that exposures to PM2.5 can cause progression of diseases among T2DM populations.
Показать больше [+] Меньше [-]Particulate matters and gaseous pollutants in indoor environment and Association of ultra-fine particulate matters (PM1) with lung function
2019
Akther, Tanzina | Ahmed, Morshad | Shohel, Mohammad | Ferdousi, Farhana Khanom | Salam, Abdus
Real-time particulate matters (PM₁, PM₂.₅, PM₄, PM₇, PM₁₀, and TSP) with AEROCET 531S (USA), gaseous pollutants (NO₂ and TVOC) with Aeroquel 500 gas sampler (NZ) were measured from the indoor air of houses at four residential locations in Dhaka, Bangladesh. PM₁₀ samples were collected on quartz filters with a dual channel dust sampler (IPM-FDS 2510, India) for selected trace metal determination from five houses of Dhaka. Respiratory function of the occupants was assessed by using a peak expiratory flow meter (Rossmax PF 120). Mean PM₁, PM₂.₅, and PM₁₀ concentrations were 46.1 ± 13.4, 76.0 ± 16.2, and 203.9 ± 44.8 μg m⁻³, respectively. Higher enrichment factors of Pb, Zn, and Ni were found for traffic, industrial, and constructional activities. The correlation between indoor and outdoor PM₂.₅ (R² = 0.42) and ratios (I/O < 1) suggesting indoor air was effected by outdoor air. The concentration of NO₂ (0.076 ± 0.007 ppm) and TVOC (90.0 ± 46.0 ppm) was found above than other studies. The average total hazard ratio (THR) in Dhaka was 9.06 and has the highest exposure to air pollutants (PM₂.₅, PM₁₀, NO₂) in Khilkhet (THR 10.1) residents. A negative association between ultra-fine particles (PM₁) and peak flow rate measurements of the residents living in these houses indicates that inhalations of ultra-fine particles has great influence on the reduced lung efficiency.
Показать больше [+] Меньше [-]The impact of several hydraulic fracking chemicals on Nile tilapia and evaluation of the protective effects of Spirulina platensis
2019
Mahmoud, Mahmoud A. | Abd El-Rahim, Abeer H. | Mahrous, Karima F. | Abdelsalam, Mohamed | Abu-Aita, Nashwa A. | Afify, Mamdouh
Hydraulic fracturing (fracking) chemicals are used to maximize the extraction of hard-to-reach underground energy resources. Large amounts of fracking fluid could escape to the surrounding environments, including underground and surface water resources, during the chemical mixing stage of the hydraulic fracturing water cycle due to equipment failure or human error. However, the impact of pollution resulting from operational discharges is difficult to assess in aquatic ecosystems. In this study, pathological investigations, chromosomal aberrations, DNA damage, and biochemical and hematological parameters were used to evaluate the effects of such chemicals on Nile tilapia. Chromosomal aberrations are considered very sensitive genetic markers of exposure to genotoxic chemicals and are used as indicators of DNA damage. The appearance of different types of chromosomal aberrations (gaps and breaks) due to chemical exposure was significantly reduced by treatment with spirulina. Various deleterious findings in Nile tilapia, in the current study, could attributed to the presence of fracking chemicals in the aquatic environment. However, the presence of spirulina in the diet reduced the hazards of such chemicals. In addition, cytogenetic studies in the current work revealed the importance of spirulina in ameliorating the genotoxic effects of a mixture of some chemicals used in fracking.
Показать больше [+] Меньше [-]Pollution intensity-dependent metal accumulation in ground beetles: a meta-analysis
2019
Tőzsér, Dávid | Magura, Tibor | Simon, Edina | Mizser, Szabolcs | Papp, Dalma | Tóthmérész, Béla
Survival of organisms in polluted habitats is a key factor regarding their long-term population persistence. To avoid harmful physiological effects of pollutants’ accumulation in organisms, decontamination and excretion could be effective mechanisms. Among invertebrates, ground beetles are reliable indicators of environmental pollution. Published results, however, are inconsistent, as some studies showed effective decontamination and excretion of pollutants, while others demonstrated severe toxic symptoms due to extreme accumulation. Using ground beetles as model organisms, we tested our pollution intensity-dependent disposal hypothesis for five pollutants (Cd, Cu, Mn, Pb, and Zn) among four soil pollution intensity levels (low, moderate, high, and extreme) by categorical meta-analysis on published data. According to our hypothesis, decontamination and excretion of pollutants in ground beetles are effective in lowly or moderately polluted habitats, while disposal is ineffective in highly or extremely polluted ones, contributing to intense accumulation of pollutants in ground beetles. In accordance with the hypothesis, we found that in an extremely polluted habitat, accumulation of Cd and Pb in ground beetles was significantly higher than in lowly polluted ones. These findings may suggest the entomoremediation potential of ground beetles in an extremely polluted environment.
Показать больше [+] Меньше [-]Total retail goods consumption, industry structure, urban population growth and pollution intensity: an application of panel data analysis for China
2019
K̲h̲ān, Zīshān | Shahbaz, Muhammad | Aḥmad, Manẓūr | Rabbi, Fazli | Siqun, Yang
There has been a growing concern regarding the regulation of environmental pollution in the face of a growing population, global warming, and climate change. Governments around the world have devised various mechanisms and policy strategies to ameliorate the worsening condition of natural environment around the world. Similar to the developed world, in China, the government is also aware of deteriorating environmental conditions. Hence, the existing abatement instruments include pollution discharge fees and several other policy strategies. This research is conducted to investigate the association between pollution intensity and its determinants, i.e., pollutant discharge fees and urban population, third industry structure, and total retail goods consumption. The secondary data of 29 provinces is used for empirical analysis. The principal component analysis is used to develop a single index called pollution intensity, and panel autoregressive distributed lags model (ARDL), or pooled mean group (PMG) analysis, is employed to find long-run and short-run relationship. The empirical findings show that pollution discharge fees negatively affects pollution intensity. Total retail good consumption and urban population increase pollution intensity. However, third industry structure helps to control pollution intensity. These results suggest reforms in the existing environmental regulations policy by targeting more pollutant intensive provinces.
Показать больше [+] Меньше [-]Preparation of chitin nanowhiskers and its application for crystal violet dye removal from wastewaters
2019
Druzian, Susanne Pedroso | Zanatta, Natalia Pollon | Côrtes, Letícia Nascimento | Streit, Angélica Fátima Mantelli | Dotto, Guilherme Luiz
Chitin (Ch) and chitin nanowhiskers (ChNW) were prepared, characterized, and applied as adsorbent to remove crystal violet (CV) dye from aqueous solutions. Ch was obtained from shrimp wastes and submitted to acid hydrolysis in order to find ChNW. The increase in average pore size and the rod-like shape of ChNW were probably the main characteristics which contributed to the increase in adsorption potential, when compared with raw Ch. The adsorbent dosage considered more adequate was 5 g L⁻¹, and the most suitable pH was 8.0. A pseudo-second-order model was adequate to represent the kinetic profile. Sips and Hill models were suitable to fit the equilibrium curves. The maximum adsorption capacity of CV on ChNW was 59.52 mg g⁻¹, and the process was endothermic, favorable, and spontaneous. These findings indicated that ChNW have potential to be used as adsorbent in the treatment of colored wastewaters.
Показать больше [+] Меньше [-]Melatonin attenuates bisphenol A-induced toxicity of the adrenal gland of Wistar rats
2019
Olukole, Samuel Gbadebo | Lanipekun, Damilare Olaniyi | Ola-Davies, Eunice Olufunke | Oke, Bankole Olusiji
This study investigated the role of melatonin (MLT) on adrenal gland toxicity induced by bisphenol A (BPA). Adult male rats were divided into four groups of seven animals each: Group I (control) received oral 0.2 ml canola oil; group II received intra-peritoneal 10 mg/kg BW/day MLT; and group III received oral BPA (10 mg/kg BW/day). Group IV rats were treated with same dose of BPA as group III with a concomitant intra-peritoneal 10 mg/kg BW/day MLT. All treatments lasted for 14 days. BPA significantly increased (P < 0.05) adrenal index, circulating levels of corticosterone and adrenocorticotropic hormone (ACTH) in the rats. BPA caused marked vascular congestion, hyperplasia, cellular distortion, increased lipid peroxidation, decreased antioxidant enzymes, and decreased expression of αSmooth muscle actin as well as vimentin proteins. The concomitant treatment with MLT ameliorated these BPA-induced alterations. It is likely that melatonin attenuates BPA-induced alterations of the adrenal gland of rats through the antioxidant defense mechanism.
Показать больше [+] Меньше [-]Comparable investigation of polyaniline behavior towards gaseous ammonia and toluene adsorption
2019
Abdelraheem, Amira | H. El-Shazly, Ahmed | Elkady, Marwa
With raising awareness of gaseous air pollutants and their harmful impact, adsorption is considered one of the most prominent techniques for gaseous emissions control. The usage of polyaniline as a gas adsorbent is an innovative idea. This work aims to compare the efficacy of synthesized polyaniline nanotubes (PANT) as a novel adsorbent towards inorganic gases (ammonia NH₃) and volatile organic compounds (toluene vapor). PANT was prepared via a sol-gel preparation technique. The molecular structure of prepared PANT was characterized by Fourier-transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD). The morphological structure was confirmed using transmission electron microscopy (TEM) and scanning electron microscope (SEM). The PANT adsorbent surface area was determined using Brunner Emmett Teller (BET). Dynamic behavior of simulated feed gas mixture of NH₃ and toluene in air were examined using a fixed bed adsorption arrangement. The same adsorption conditions (inlet concentration, gas mixture feed flow rate, and a fixed amount of adsorbent) were applied for both NH₃ and toluene adsorption test. The NH₃ and toluene removal efficiencies were 100% and 96% respectively. Consequently, PANT is an auspicious adsorbent that can be utilized to control the indoor and outdoor gaseous air emissions. Graphical Abstracts ᅟ
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