Accumulation of heavy metals in agricultural soil irrigated by sewage sludge and industrial effluent (case study: Agh ghallah industrial estate)

Background and purpose: Industrial effluent and sewage sludge are used as fertilizer since they contain high levels of nutrient. The main pollutant in industrial effluent is heavy metals. In this study an assessment was made on the impact of industrial wastewater effluent and sewage sludge on accumulation of heavy metals in agricultural soil at Agh ghallah industrial Estate. Materials and methods: In a descriptive-analytic study, 72 samples (sewage sludge, effluent and soil) were collected from the Industrial state. All sampling and tests were performed according to standard methods and concentration of heavy metals was determined using polarography method. To analyze the data, SPSS was used and 95 confidence intervals (P 0.05). Conclusion: The concentrations of heavy metal were found lower than the maximum allowable level. Therefore, in this area, wastewater and sewage sludge could be used to irrigate agricultural lands and greenspaces in shortage of water, however, environmental regulations should be taken into account. © 2015 Mazandaran University of Medical Sciences. All rights reserved

Leaching characteristics of the fine fraction from an excavated landfill: physico-chemical characterization

Leaching of fine fraction (<10 mm) obtained from landfill mining activities in an Estonian landfill was done. On-site excavation was carried out in four test pits (TP1, TP2, TP3, TP4) that were further divided in four layers (L1, L2, L3, L4). Total chemical oxygen demand (CODt), dissolved chemical oxygen demand (CODd), total organic carbon (TOC), dissolved organic carbon (DOC) and metals (Zn, Cu, Pb and Cd) were analyzed. The results showed that approximately 70 % of CODt were in particulate/colloidal state. The TOC released ranged between 2326 and 3530-mg/kg dry matter for test pits suggesting spatial differences in the studied landfill. DOC ranged between 365–874 and 317–940 mg/kg for different test pits and sampling layers, respectively. Low average leaching rates of metals were observed (0.2–1.5 %). Pb had a significantly higher average leaching rate (1.0 %) compared to Zn (0.70 %) and Cu (0.35 %). The potential use of CODt as a surrogate indicator of TOC, DOC and Zn on the basis of high correlation coefficients was observed. To conclude, the implementation of adequate strategies to manage fine-grained fractions obtained from excavated waste relies on physico-chemical characterization of both the fine fractions itself and the leachate generated during storage and use. © 2015 Springer Japa

A Light, Transmission and Scanning Electron Microscope Study of Snuff-Treated Hamster Cheek Pouch Epithelium

The effects of smokeless tobacco (snuff) on hamster cheek mucosa were studied by light microscopy, transmission (TEM) and scanning electron microscopy (SEM). Two grams of commercially available smokeless tobacco were placed into the blind end of the right cheek pouch of each experimental animal, once a day and five days a week for 24 months. The control animals did not receive smokeless tobacco. After 24 months treatment with smokeless tobacco, hamster cheek mucosal epithelium lost its translucency and had become whitish in color. By light microscopy hyperorthokeratosis, prominent granular cell layers with increased keratohyalin granules and hyperplasia were seen. At the ultrastructural level, wider intercellular spaces filled with microvilli, numerous shorter desmosomes, many thin tonofilament bundles, increased number of mitochondria, membrane coating granules and keratohyalin granules were seen in snuff-treated epithelium. The changes in the surface of the epithelium as seen by SEM were the development of an irregular arrangement of the microridges and the disappearance of the normal honeycomb pattern. The microridges were irregular, widened and surrounded the irregular elongated pits. Some smooth areas without microridges and pits were also seen. The long-term histological, TEM and SEM changes induced by smokeless tobacco treatment of the epithelium are well correlated with each other and were similar to those reported in human leukoplakia without dyskeratosis. They imply changes of pathological response resulting from topically applied snuff

Monitoring of tuna resources (yellowfin and skipjsck tunas) in Oman Sea along Sistan & Balouchestan coastal waters

Collecting of biometric parameters and catch and effort data were made for yellowfin and skipjack tunas from artisanal gillnet and industrial purse seine fisheries during the years 2002-2004 in Oman Sea along Sistan and Balouchestan coastal waters. The previous available data was used for the purpose of better monitoring the resources. The frequency of maturity stages and GSI values obtained from yellowfin showed a spawning period from February to May, peaking in April-May. For skipjack, the data indicated a long spawning period which beganed in December with peaking in April-May. LM50% was obtained as 83.1 and 62.4 for yellowfin and skipjack tunas respectively. Sex ratio by size group showed a predominance of males with larger fish. Analysis of stomach contents showed a significant proportion for the both species. The composion of food contents by occurrence method revealed that fish were the most dominant food items by year for the specise. Presence of squilla, crabs, shrimps (Larval stage), belonging to Peneaidea family, in large quantities were the oblivious food items so that they had not been reported by previous studies. Blooming of squilla, Natosquilla investigators, in the western Indian Ocean provided a situation to be observed in large occurrence in yellowfin and skipjack stomach contents. The ratio was more in yellowfin stomachs when compared to skipjack ones which accounted for 38%, 19% and 35% of the total stomachs studied by the study year. The shrimps prey were only observed in skipjack gut contents (with exception of one case in yellowfin stomach) which were the second major component in 2002 and 2003(24% and 17% respectively). Comparsion of mean length showed a sharp decrease from 1992 to 2004 for the species. Regarding yellowfin the mean length from 93.2 cm FL in 1992 reached to 83.2 cm FL in 2004 and from 64.95 to 58.51 cm FL for skipjack. In spite of decreasing mean length for yellowfin, the value increased in 2004 in comparison to 2003 which was in agreement with Indian Ocean data. Comparative analysis of length frequency with LM50% indicated that immature fish were the major part of the catch. There are available information on population dynamic parameters. A comparative analysis of CPUE,s (kg/panel.day) from artisanal gillnet fishery for yellowfin and skipjack tunas revealed a decreased value by fishing craft class in 2005 when compared to 1998 data, but increased in 2003. Increased trend of the species catches by fishing craft class was due to increased fishing effort. Analysis of the statistical catch and effort data for the study years, irrespective of fishing craft class, showed that total landings of the species have increased 4.4 fold in spite of attaining CPUE to 7% in decrease which was a consequence of increased fishing effort up to 4.7 fold. The CPUE, s (tons / positive set) from industrial purse seine fishery increased in 2003 and 2004(39% and 10% respectively), but declined up to 54% in 2005. The trend is in agreement with purse seine fishery data from Indian Ocean where the increased values were attributed by larger size of yellowfin. The purse-seine fishing ground data revealed that the major sets were made in Persian Gulf, whereas a shift towards Oman Sea in eastern part of Sistan and Balouchestan coastal waters is recommended to be a suitable fishing area for the first half of year and towards offshore waters in Indian Ocean for the second half of year. For attaining a sustainable fishery system, it is recommended to regulate the gillnet mesh size and introduce longline fishery in the area along with stopping any further increased fishing effort in artisanal gillnet fishery

Biomass estimation of demersal resources in the Persian Gulf and Oman Sea by swept area method

Regarding to monitor of demersal resources in the Persian Gulf and Oman Sea, and also biomass and CPUA estimation of them, ten research cruises were carried out by using R/V Ferdows-1 equipped with bottom trawl, covering the area from 49º 00´ E in the west (north-west Persian Gulf) to 61º 25´ E in the east (borderline with Pakistan) from 2012 to 2014 The study area was stratified into 17 strata (A to Q) of which 10 strata (A to J) were in the Persian Gulf and 7 strata (K to Q) were in the Oman Sea, covering the depths of 10-50 m in the Persian Gulf and 10-100 m in the Oman Sea. A total of 316 stations were randomly selected and the biomass and CPUA were estimated by swept area method during this three years period, the strat A and B weren’t covered. The comparison between two regions indicated that the percentage of density of demersal fishes in the Persian Gulf during years 2012, 2013 and 2014 were 1.0, 1.4 and 1.6 times more than the Oman Sea and totally 50-60% of total biomass was found for the Persian Gulf. Also a comparison among 17 strata the highest biomass was found for K region (Sirik to Jask) in the Oman Sea in 2012 & 2014; and C region (Genaveh to Bordkhoon) in 2013 in the Persian Gulf. The same comparison was done for CPUA of commercial, non-commercial and total in both water bodies and it was found that in years 2012 to 2014 the region K (Sirik to Jask) in the Oman Sea and Stratum Q (Bersi to Gwatr) had the highest value of CPUA. On the contrary, the stratum M (Biahi to Galak estuary) showed the lowest value of biomass for both commercial and non-commercial fishes. With review the mean CPUA in different depth layers for years 2012, 2013 and 2014, it was concluded that in the Oman Sea with increasing the depth, the mean CPUA is decreased and the lowest CPUA belongs to depths of 30-50 m The comparison between commercial and non-commercial groups in both ecosystems, it concluded that the density of commercial species were higher than non-commercial ones; and for years 2009, 2010 and 2011 the commercial species consist of 63.4, 65.0 and 59.7 % of total biomass. In all years the Persian Gulf indicated higher values than the Oman Sea. The most abundant fishes were Rays, Ribbon fishes, Carangids, Grunts, Japanese threadfin bream, Lizardfish and Barracuda for both Persian Gulf and Oman Sea

Investigating the feasibility of removing the rapid mixing unit in conventional surface water treatment and its effect on turbidity removal

Coagulation and flocculation processes play a major role in surface water treatment. The aim of this study was to eliminate the rapid mixing unit in the water treatment plant. This experimental study was conducted on turbid water. Turbid water was synthesized by kaolin powder. The conventional jar test method was used. The flocculation and sedimentation processes were performed on the turbid water without a rapid mixing unit for getting the new optimal condition. When the PACl coagulant was used alone and in conjunction with chitosan, the percentages of turbidity removal in low, medium and high turbidities were obtained as 86.7, 95.8, 97.8 and 86.67, 95.73, 98.26, respectively. When the rapid mixing unit was emitted, the efficiency of turbidity removal in the low turbidity was reduced from 5.26 to 21.73. But, in higher turbidity in two states (presence and absence of the rapid mixing units) it did not have a significant difference. This study showed that the removal of the rapid mix unit on the removal efficiency of turbidity in the low turbidity is effective, but does not have an effect on higher turbid water. Also, using PACl in conjunction with chitosan was effective in the removal efficiency and to reduce residual aluminum. © 2021 The Authors

Residual Aluminum from application of Alum and Polyaluminum Chloride in removal of turbidity from turbid water

Background and Objective: Different coagulants including aluminum sulfate (Alum) and Polyaluminum Chloride (PAC) are used for water clarification process and deposition of colloidal particles. The use of coagulants causes some residual aluminum in water. The residual aluminum higher than 0.2 mg/l, has adverse effects on human health and environment. This study was conducted to determine the amount of residual aluminum by applying Polyaluminium chloride and aluminum sulfate for turbidity removal from turbid water. Methods: In this laboratory study, the experiments were run by using synthetic water having low (10-30 NTU), medium (100-130 NTU) and high (200-230 NTU) initial turbidities. Synthetic turbid water was prepared by adding stock kaolin suspension into distilled water. Samples of 1 liter of water were poured on 6 Jars. After adjusting of pH, coagulant was added into each beaker at various doses and agitated at 100 rpm for 30s. The mixing speed was then reduced to 20 rpm and kept for another 15 minutes. The suspensions were left for sedimentation and after 30 minutes of sedimentation, clarified samples were collected from the top of the beakers. Residual turbidity and residual aluminum was measured. The residual turbidity was measured using a Turbidimeter according to Nephlometric method. The residual aluminum was determined by Eriochrome cyanine R method. Results: Residual alminium in low, medium and high turbidities was 0.006 mg/l, 0.05 mg/l and 0.07 mg/l by applying Polyaluminum Chloride and 0.065 mg/l, 0.15 mg/l and 0.22 mg/l by applying alum, respectively. There was a significant correlation between dosage of Alum and Polyaluminum Chloride with residual aluminium (P<0.05). Conclusion: Polyaluminum Chloride due to low sensitivity to pH variation and less residual aluminum in treated water is more suitable than alum coagulant and could be used as a recommended water coagulant

Adsorption of pb(Ii) from aqueous solutions by montmorillonite/fe3 o4 nanoparticles: Batch and column studies

In the present study, magnetic montmorillonite (MMT/Fe3 O4 ) was prepared using chemical precipitation for adsorption of Pb(II) and was characterized by scanning electron microscopy, transmission electron microscopy, thermogravimetric analysis, X-ray diffraction and Fourier-transform infrared spectroscopy (FTIR). The results showed that Fe3 O4 uniformly occurred on MMT. The maximum adsorption capacity of Pb(II) by MMT/Fe3 O4 was obtained to be 36.76 mg/g, which was higher than the Fe3 O4 and MMT alone. The removal efficiency of Pb(II) was strongly dependent on the operating factors, where the maximum efficiency occurred at pH of 5, adsorbent dose of 0.4 g/L, Pb(II) concentration of 30 mg/L, stirring rate of 300 rpm, and contact time of 120 min. The adsorption data followed the Langmuir isotherm, and the kinetic results showed that the chemisorption process is the dominant mechanism for Pb(II) removal. The results of the FTIR analysis explained that the Al�OH and Fe�O functional groups have high participation in pollutant adsorption. The column study emphasized that MMT/Fe3 O4 nanocomposite has excellent efficiency in the treatment of real wastewater containing Pb(II). In addition, excellent magnetic separation and regeneration performance indicated the applicability of adsorbent for the treatment of synthetic and real solutions. © 2021 Desalination Publications. All rights reserved

Evaluation of diagnostic characteristics and predictors of appropriate ICD therapy in patients with arrhythmogenic right ventricular cardiomyopathy

Background: Arrhythmogenic right ventricular cardiomyopathy dysplasia (ARVCD) is a common cause of sudden cardiac death among young adults and athletes. The currents study sought to evaluate clinical characteristics, echocardiographic and ECG diagnostic criteria, and follow-up results in patients with ARVCD. Methods: In the present case series, the ECG, imaging, and echocardiography records of all patients referring to our tertiary care center between 2000 and 2015 were assessed. Sex, age, cardiovascular risk factors, drug history, and family history of cardiovascular diseases were considered as the study variables. The frequency of all baseline and clinical data and the correlations between those and implantable cardioverter defibrillator (ICD) indication and survival were evaluated. Results: In this case series, 68 patients with ARVCD (mean age =39.48±15.83 y; 45 male) were evaluated. The most frequent symptom was palpitation, followed by syncope, and the most prevalent ECG findings was T-wave inversion in the precordial leads (P<0.05). Regional RV akinesia or dyskinesia was seen in 77.9. The ICD was implanted in 55 patients: appropriate and inappropriate therapy was seen in 33 and 12 patients, respectively. The correlation between dyspnea and ICD indication was significant (P<0.05). The relationships between appropriate ICD therapy and dyspnea, peripheral edema, ascites, and severe left ventricular (LV) dysfunction were significant (P<0.05). Multivariate analysis showed that dyspnea and secondary ICD indices were the predictors of appropriate ICD therapy. The mortality rate was 11.8. Conclusions: In our patients with ARVCD, the most common symptoms were palpitation, syncope, and T-wave inversion in the precordial leads. The correlations between appropriate ICD therapy and dyspnea, peripheral edema, ascites, and severe LV dysfunction were significant. Dyspnea and secondary ICD indication were the predictors of appropriate ICD therapy. © 2016, Iranian Heart Association. All rights reserved

Adsorption of methylene blue from aqueous solutions by cellulose and nanofiber cellulose and its electrochemical regeneration

This study was conducted to evaluate the potential of the bleached bagasse, cellulose, and nanofiber cellulose to remove methylene blue (MB) from aqueous solution. The morphology of adsorbents surface and their functional groups were examined by using scanning electron microscope and Fourier transform infrared spectroscopy techniques, respectively. In a batch mode study at 25°C temperature, the effects of initial dye concentration, contact time, adsorbent dose, and solution pH on adsorption performance were investigated. The results showed that the percent of MB removal increases by increasing pH and also by increasing sorbent dosage and decreasing initial dye concentration. The adsorption kinetics and equilibrium data were in good agreement with the pseudo-second-order kinetic model and Freundlich adsorption isotherm, respectively. The removal of MB was better and more effective with cellulose and cellulose nanofiber as compared with the bleached bagasse. The regeneration of cellulose and nanofiber cellulose loaded with MB was investigated using electrochemical method under different operating conditions. The results showed that the electrochemical process efficiency is more than 60 for regeneration adsorbents. © 2018 Desalination Publications. All rights reserved