Refine search
Results 1-10 of 365
Studying Some Blood Parameters of Otolithes ruber (Schneider, 1801) in Cold and Warm Seasons as an Indicator of Pollution in Musa Creek
2021
Ghasemi, Hamideh | Abdi, Rahim | Doraghi, Abdulmajed | Salamat, Negin | Salari-Aliabadi, Mohammad Ali
The present study attempts to investigate some blood parameters of Otolithes ruber during different seasons in terms of both temperature and pollution. For so doing it uses 10 specimens, for each station and season, collected from 5 polluted stations, including Petrochemical, Ghanam, Zangi, Douragh, Patil, and Sajafi as the control group, away from pollution in Musa Creek. The fish are anesthetized with 1ml of clove extract per liter. Their blood samples are taken immediately from the caudal vein, using a heparinized syringe. Afterwards, the serum is separated in a centrifuge with a speed of 6000 rpm for 2 minutes. The desired factors are measured by the Mindray BS200 auto-analyzer and the total protein level, by Bradford's usual laboratory methods. Results show that AST, ALT, ALP, Glucose, and Triglycerides have increased in more polluted stations (P≤0.05). In sheer contrast, total protein and Albumin have decreased as pollution grows (P≥0.05). According to this study, environmental water pollution of the fish has a large impact on the concentration of measured blood parameters, whereas the influence of seasonal changes on most of them is low.
Show more [+] Less [-]Batch and Column Studies on Nickle and Cadmium Removal Using Iranian Clay-based Geopolymer
2021
Bakhtiari, Somayeh | Zeidabadinejad, Asma | Abbaslou, Hanieh | Ghanizadeh, Alireza
The production rate of industrial and agricultural waste is increasing due to population growth. Soil is the most important receiver of industrial and agricultural waste. Contaminants such as heavy metals in various waste after reception by the soil, immediately become part of the cycle that has different impacts on the environment. Geopolymer, as a chemical stabilizer has the potential to stabilize heavy metals in the soil. In this research, several geopolymers for the stabilization of heavy metals in soil were synthesized. Silicon dioxide (SiO2) and aluminosilicate (Al2SiO4) must be used to produce the geopolymers. Rice husk ash was used as the SiO2 source. Also, Iranian zeolite and sepiolite, and red clay soil were utilized as the source of Al2SiO4. The synthesized geopolymers were investigated for the adsorption of nickel and cadmium. Also, batch and column studies of using geopolymers for the chemical stabilization of heavy metals in soil were conducted. The results revealed a high adsorption capacity of the geopolymers. The zeolite, sepiolite, and red clay geopolymer-soil samples adsorbed 100% of the heavy metals (i.e., Ni and Cd) at a concentration of 100 ppm. The zeolite geopolymer adsorbent adsorbed 57% and 96% of Ni and Cd at a concentration of 1000 ppm, respectively. In general, it was concluded that the use of geopolymer compounds in soils with high heavy metal adsorption capacity could be an efficient approach to prevent groundwater resource pollution.
Show more [+] Less [-]Water Quality Assessment in Urban Wetlands and Suitability for Fish Habitat: A Case Study
2021
Dixit, Arohi | Siva Siddaiah, Neelam | Singh Chauhan, Jogindar | Ullah Khan, Waseem
In this study, water from three urban wetlands of Gurugram – Sultanpur (WS), Damdama (WD), and Basai (WB), was studied for various physicochemical parameters to assess their suitability for the healthy survival of fishes and the results were compared with the limits of these parameters for fish farming. The parameters studied were colour, temperature, pH, alkalinity, hardness, Ca2+- Mg2+ ratio, NO3-, Cl-, SO42-, PO43-, and heavy metals (Fe, Mn, Cr, Cu, Zn, Ni and Pb). The results of the study indicate the majority of studied parameters are beyond the desirable limits in WB; thus, water is most unsuitable for fishes in WB. WB is unsuitable for parameters: colour, alkalinity, hardness, Ca -Mg ratio, NO3-, Cl-, SO42-, PO43-, Cr, Cu, Fe, Mn, Ni and Zn. WS needs consideration for temperature, NO3-, Cu, Ni and Zn, whereas WD needs improvement in temperature, TDS, NO3-, Cr, Cu, Fe, Mn, Ni and Zn concentration for better fish growth. Most of the parameters are high in summer as compared to winter, which is due to the dilution after rainfall. Hence, we recommend timely action for effective measures to improve the water quality of wetlands and their regular monitoring for improved fish habitat.
Show more [+] Less [-]Improving Phytoremediation Efficiency of Copper-spiked Calcareous Soils by Humic Acid Applications
2021
Saffari, Vahid Reza | Saffari, Mahboub
In current study, the enhanced efficiency of copper (Cu) phytoremediation potential of Calendula officinalis L. was investigated in a Cu-spiked calcareous soil, using foliar and soil application of humic acid. For this purpose, in a greenhouse experiment, seedlings of C. officinalis were transferred to Cu-spiked soils (0, 250 and 500 mg/kg) and treated separately with soil (soil drench) and foliar (spraying plant leaves) humic acid applications at different levels (0, 10, 20 μM). The humic acid treatments were applied 2 weeks after transferring plant, and eventually the various biochemical-physiological traits and phytoremediation indices of Cu in C. officinalis were measured at (specific) time points. According to the results, C. officinalis grew normally without any toxicity signs in Cu-spiked soils, however with increasing the Cu levels, the dry weight biomass decreased and antioxidant enzymes activities increased. Both foliar and soil humic acid application in Cu-spiked soils increased dry weight biomass, photosynthetic pigment contents, Cu concentration, and bioconcentration factor (BCF). Furthermore, the application of this organic substance, obviously moderated the Cu stress since the antioxidant enzymes activities reduced compared to the control. Based on the results, the obtained translocation factor (TF) and BCF values of Cu, which were >1, indicated that this plant is a Cu-hyperaccumulator, which could extract Cu via phytoextraction mechanism. Generally, the results of this study showed that, among the humic acid treatments, application of 20 μM (especially soil drench application) had the best effect on increasing Cu phytoremediation efficiency in the studied soil and it recommended to enhance the efficiency of Cu phytoremediation in calcareous soils.
Show more [+] Less [-]Characterization and Assessment of Stormwater Runoff Quality from Automobile Workshops in Nigeria Using Multivariate Linear Regression
2021
C.O. Ataguba | I. C. Brink
An investigation into the pollution of stormwater runoff from automobile workshops in Nigeria was performed. Also, multivariate regression was used to predict the pH, oil, and grease (O&G) as well as the electrical conductivity (EC) in relation to the characteristics of the solids and metals pollutants of the untreated automobile workshop stormwater. The results indicated that automobile workshops contributed notable amounts of pollutants to stormwater runoff. Results were compared with Nigerian and USEPA standards. It was found that most of the parameters had mean value ranges far greater than standard limits. The multivariate regression showed variations in the results obtained from different automobile workshops. These variations could be due to the influence of factors such as the volume of automobile servicing activities and the waste generated from these activities that flow in the stormwater runoff. However, the bulk of the EC and pH of the stormwater were associated with the concentrations of the total dissolved solids and copper while the bulk of the O&G concentration was associated with the concentrations of lead and cadmium. It is recommended to treat automobile workshop stormwater to prevent detrimental effects in aquatic systems. Future research is aimed at modeling such treatment using multivariate regression techniques is warranted.
Show more [+] Less [-]Cadmium exposure induces osteoporosis through cellular senescence, associated with activation of NF-κB pathway and mitochondrial dysfunction
2021
Luo, Huigen | Gu, Renjie | Ouyang, Huiya | Wang, Lihong | Shi, Shanwei | Ji, Yuna | Bao, Baicheng | Liao, Guiqing | Xu, Baoshan
Cadmium (Cd) is a heavy metal toxicant as a common pollutant derived from many agricultural and industrial sources. The absorption of Cd takes place primarily through Cd-contaminated food and water and, to a significant extent, via inhalation of Cd-contaminated air and cigarette smoking. Epidemiological data suggest that occupational or environmental exposure to Cd increases the health risk for osteoporosis and spontaneous fracture such as itai-itai disease. However, the direct effects and underlying mechanism(s) of Cd exposure on bone damage are largely unknown. We used primary bone marrow-derived mesenchymal stromal cells (BMMSCs) and found that Cd significantly induced BMMSC cellular senescence through over-activation of NF-κB signaling pathway. Increased cell senescence was determined by production of senescence-associated secretory phenotype (SASP), cell cycle arrest and upregulation of p21/p53/p16ᴵᴺᴷ⁴ᵃ protein expression. Additionally, Cd impaired osteogenic differentiation and increased adipogenesis of BMMSCs, and significantly induced cellular senescence-associated defects such as mitochondrial dysfunction and DNA damage. Sprague-Dawley (SD) rats were chronically exposed to Cd to verify that Cd significantly increased adipocyte number, and decreased mineralization tissues of bone marrow in vivo. Interestingly, we observed that Cd exposure remarkably retarded bone repair and regeneration after operation of skull defect. Notably, pretreatment of melatonin is able to partially prevent Cd-induced some senescence-associated defects of BMMSCs including mitochondrial dysfunction and DNA damage. Although Cd activated mammalian target of rapamycin (mTOR) pathway, rapamycin only partially ameliorated Cd-induced cell apoptosis rather than cellular senescence phenotypes of BMMSCs. In addition, a selective NF-κB inhibitor moderately alleviated Cd-caused the senescence-related defects of the BMMSCs. The study shed light on the action and mechanism of Cd on osteoporosis and bone ageing, and may provide a novel option to ameliorate the harmful effects of Cd exposure.
Show more [+] Less [-]A synthesis framework using machine learning and spatial bivariate analysis to identify drivers and hotspots of heavy metal pollution of agricultural soils
2021
Yang, Shiyan | Taylor, David | Yang, Dong | He, Mingjiang | Liu, Xingmei | Xu, Jianming
Source apportionment can be an effective tool in mitigating soil pollution but its efficacy is often limited by a lack of information on the factors that influence the accumulation of pollutants at a site. In response to this limitation and focusing on a suite of heavy metals identified as priorities for pollution control, the study established a comprehensive pollution control framework using factor identification coupled with spatial agglomeration for agricultural soils in an industrialized part of Zhejiang Province, China. In addition to elucidating the key role of industrial and traffic activities on heavy metal accumulation through implementing a receptor model, specific influencing factors were identified using a random forest model. The distance from the soil sample location to the nearest likely industrial source was the most important factor in determining cadmium and copper concentrations, while distance to the nearest road was more important for lead and zinc pollution. Soil parent materials, pH, organic matter, and clay particle size were the key factors influencing accumulation of arsenic, chromium, and nickel. Spatial auto-correlation between levels of soil metal pollution and industrial agglomeration can enable a more targeted approach to pollution control measures. Overall, the approach and results provide a basis for improved accuracy in source apportionment, and thus improved soil pollution control, at the regional scale.
Show more [+] Less [-]Distribution and partitioning of heavy metals in water and sediments of a typical estuary (Modaomen, South China): The effect of water density stratification associated with salinity
2021
Jia, Zhenzhen | Li, Shiyu | Liu, Qiuxin | Jiang, Feng | Hu, Jiatang
Many estuaries have undergone severe saltwater intrusion in addition to simultaneously experiencing serious heavy metal pollution. To explore the effect of water density stratification associated with saltwater intrusion on the behaviour of heavy metals (Cr, Co, Ni, Cu, Zn, As, Pb, and Cd) in water and sediments, a field survey was conducted in a typical estuary (Modaomen). The content, distribution, and mobility of heavy metals were investigated, as well as the influence of environmental factors on their future. The results showed that Modaomen estuary was characterised by a notable variation in salinity along the estuary, presenting total freshwater upstream, high salinity stratification water in the mouth, and saltwater offshore. Dissolved metals presented a prominent gradient vertically, with 1.2–2.1 times higher in bottom water than in surface water and the highest contents in the highly–stratified bottom water. Elevated salinity and restricted mixing induced by water stratification were likely the causes of this outcome. The distribution of heavy metals in sediments was greatly governed by grain size, Fe/Mn (hydr)oxides, total organic carbon, salinity, and dissolved oxygen. Comprehensive evaluation, combined with total contents and chemical fractions of heavy metals, indicated that internal release from sediments contributed a considerable part to the higher levels of heavy metals in bottom water, particularly for Zn and Pb, which was fully consistent with their status in water body, and elevated salinity and lack of oxygen were likely the primary driving factors. During the phase-partition processes between bottom water and sediments, partitioning coefficients were markedly lower in the highly stratified zone, implying that saltwater intrusion facilitated the mobility and repartitioning processes of metals. Because of increased levels and toxicity of heavy metals in water and extended residence time during saltwater intrusion, the potential damage to the estuarine ecosystem should receive more attention.
Show more [+] Less [-]Assessment of the ability of roadside vegetation to remove particulate matter from the urban air
2021
Kończak, B. | Cempa, M. | Pierzchała, Ł | Deska, M.
The development of urbanised areas together with the growing transport infrastructure and traffic volume are the main cause of air quality deterioration due to the increasing concentrations of particulate matter. Dust pollution is a threat to human health. It can cause the development of lung, larynx or circulatory system cancer. Due to the ability to accumulate dust particles on the leaf surface, the contribution of trees in the process of phytoremediation of air pollution has started to be appreciated. An analysis of the elemental composition of particulate matter (PM) stored on the leaves surface was also carried out, which showed high average concentration of: C > O > Si > Fe (above 8wt.%). It was also observed single particles with a high concentration of heavy metals: Ti, Mn, Ba, Zn, Cr, Pb, Sn, Ni and REE (rare earth elements). The major origin of PM are vehicular emissions, soil and re-suspended road dust. This paper presents also a comparison of selected tree, shrub and vine species differing in their ability to accumulate particulate matter. It was experimentally determined the average leaf surface of individual plant species and established the amount of particulate matter with aerodynamic diameter between 10 and 100 μm, 2.5 and 10 μm, and 0.2 and 2.5 μm deposited on the leaf surface and in waxes.Some species of vines (Parthenocissus quinquefolia), shrubs (Forsythia x intermediata) and coniferous trees, such as Betula pendula ‘Youngii’, Quercus rubra, Cratageus monogyna, Acer pseduoplatanus, Tilia cordata Mill. or Platanus orientalis turned out to be the most efficient in the process of phylloremediation.
Show more [+] Less [-]Ecological network analysis reveals distinctive microbial modules associated with heavy metal contamination of abandoned mine soils in Korea
2021
Chun, Seong-Jun | Kim, Young-Joong | Cui, Yingshun | Nam, Kyong-Hee
Heavy metal pollution in soil around abandoned mine sites is one of the most critical environmental issues worldwide. Soil microbes form complex communities and perform ecological functions individually or in cooperation with other organisms to adapt to harsh environments. In this study, we investigated the distribution patterns of bacterial and fungal communities in non-contaminated and heavy metal-contaminated soil of the abandoned Samkwang mine in Korea to explore microbial interaction mechanisms and their modular structures. As expected, the bacterial and fungal community structures showed large differences depending on the degree of heavy metal contamination. The microbial network was divided into three modules based on the levels of heavy metal pollution: heavy metal-tolerant (HM-Tol), heavy metal-mid-tolerant (HM-mTol), and heavy metal-sensitive (HM-Sens) modules. Taxonomically, microbes assigned to Vicinamibacterales, Pedosphaeraceae, Nitrosomonadaceae, and Gemmatimonadales were the major groups constituting the HM-Tol module. Among the detected heavy metals (As, Pb, Cd, Cu, and Zn), copper concentrations played a key role in the formation of the HM-Tol module. In addition, filamentous fungi (Fusarium and Mortierella) showed potential interactions with bacteria (Nitrosomonadaceae) that could contribute to module stability in heavy metal-contaminated areas. Overall, heavy metal contamination was accompanied by distinct microbial communities, which could participate in the bioremediation of heavy metals. Analysis of the microbial interactions among bacteria and fungi in the presence of heavy metals could provide fundamental information for developing bioremediation mechanisms for the recovery of heavy metal-contaminated soil.
Show more [+] Less [-]