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Polycyclic aromatic hydrocarbons have adverse effects on the organisms, plants, and soil structure. Therefore, they should be removed by an appropriate and effective method. In this study, simultaneous removal of 500 mg/kg(soil) of phenanthrene and pyrene was investigated for the individual and combined application of Tween 80, Triton X-100, and sodium persulfate from the alluvial soil. The results revealed that the maximum removal efficiencies of phenanthrene (94.06 +/- 0.30%) and pyrene (90.07 +/- 0.19%) were observed in the presence of Triton X-100 + sodium persulfate (0.5 M) within 1 hour, respectively. Also, individual application of surfactants and sodium persulfate had efficiencies of less than 80%. It should be noted that the removal of phenanthrene and pyrene followed the first-order kinetic model. Economic evaluations of combined treatment demonstrated that the application of more proportion of Triton X-100 (10000 mg/L) + less proportion of sodium persulfate (0.3 M) is more cost-effective for the remediation of soil in the field study. Based on the results, the combined application of the washing process by Triton X-100 and persulfate oxidant can significantly improve the removal efficiencies and is a promising technique in the remediation of polycyclic aromatic hydrocarbons contaminated soil.

Recurrence of hydatidosis may results from cyst fluid spillage during surgery. To inactivate the cyst content, different scolicidal agents have been introduced. Nevertheless, novel and more effective treatments are needed due to the associated complications. In the current study, we examined the scolicidal effects of gold nanoparticles on Echinococcus granulosus protoscoleces. Hydatid cysts of sheep liver were collected in this study. The cyst fluid containing protoscoleces was aspirated aseptically. The protoscoleces were exposed to gold nanoparticles at different concentrations (250, 500, 1000, 2000, and 4000 μg/mL). Eosin staining method was applied to determine the viability of protoscoleces at 5, 10, 20, 30, and 60 min. Moreover, cytotoxicity analysis, scanning electron microscopy (SEM) of ultrastructural changes, DNA fragmentation, were performed, and protoscoleces were studied following treatment. The significant scolicidal effects of gold nanoparticles were observed at all concentrations compared to the control group. A total of 4000 μg/mL of gold nanoparticles could destroy 76% of protoscoleces in 60 min. Cytotoxic effects of gold nanoparticle on J774 macrophage cell line, in minimum and maximum concentration (500 and 4000 μg/mL), were 1 and 11%, respectively. After treatment of protoscoleces with gold nanoparticles in different times and concentrations, considerable alteration in size, ultrastructure changes in tegument and shape of sucker, as well as DNA fragmentation of parasite were seen. Based on the results, gold nanoparticles could exert scolicidal effects on hydatid cyst protoscoleces; therefore, they can be applied in hydatid cyst treatment.

Aniline with a benzene ring in its structure is a toxic, carcinogenic and mutagenic compound that causes many diseases in humans. Various methods have been developed to remove this pollutant from the environment among which the advanced oxidation has been successful in obtaining higher aniline removal efficiency. In this study, a UV light and Fe3O4 nano catalyst were used to remove aniline. In this study, the efficiency of aniline removal was studied as a dependent variable and aniline, hydrogen peroxide and iron nano catalyst concentrations, time and pH were investigated as independent variables. The concentration of aniline was measured by spectrophotometer. The optimization of the process was determined using the response surface method design and the central composite design model. Design Expert software was used to analyze the data. The results showed that the aniline removal efficiency decreased with increase in nano-catalyst concentration, hydrogen peroxide concentration and time and decreased with increasing pH and aniline concentration. To achieve maximum efficiency (78.1%), the optimal values for pH; initial concentration; time; nanoparticle content and H2O2 content were 3.2; 101 mg L-1; 50 min; 0.45 g L-1 and 31.08 mmol L-1. The results showed that the photo-Fenton process has a desirable ability to remove aniline from aqueous solution at pilot scale. Therefore, it was suggested to study the efficiency of this process as one of the clean and environmentally friendly methods at full scale on real wastewater.

Phenol and its derivatives constitute widespread water pollutants. They have been found to accelerate tumor formation, cancer, and mutation. In this paper, walnut shell residue has been used as a raw material in preparation of powder activated carbon by the method of chemical activation with zinc chloride for the adsorption of phenol from dilute aqueous solutions. The influence of the mass impregnation ratio (R = ZnCl2 /walnut shell) and physical activation by the CO2 stream on the physical and chemical properties of the prepared carbons was examined. The effects of main parameters such as contact time (t), initial phenol concentration (Co), and solution’s pH were studied on phenol adsorption. The maximum uptake of phenol at 25°C was 214 mg g–1 at pH near phenol pKa and Co = 1,000 mg L–1. All data were fitted well with Langmuir isotherm, but after CO2 modification, deviation from Langmuir shows that both physical and chemical adsorption occurred during adsorption. The kinetic data were fitted to different models such as pseudo-first-order, pseudo-second-order, and diffusion model. Pseudo-second-order model has been chosen as the best model. In overall, walnut shell shows excellent adaptive characteristics for the removal of phenol and appears as a very promising sorbent due to its high uptake capacity and to its low cost. © 2018 Desalination Publications

Copper, a heavy metal, causes environmental pollution through a variety of industrial processes in many countries. Adsorption is known as an effective and efficient way of removing heavy metals. The present study was conducted mainly to magnetize the carbon in wax bean waste with magnetite nanoparticles and use it as adsorbent to remove copper from aqueous solution. Carbon was obtained from wax beans waste and activated with magnetite nanoparticles. The characteristics of obtaining adsorbent were studied and analyzed by FE-SEM, BET, and FT-IR. In this study, the effect of pH, adsorbent dose, contact time and copper concentration on the efficiency of copper removal was investigated per full factorial design by the Design Expert Software. The concentration of copper was measured by atomic absorption spectrophotometer (Varian AA240). For statistical analysis of the experiment’s data, ANOVA and P-value were used. Copper initial concentration 100 mg/L, adsorbent dose 1 g/L, pH 7 and contact time 40 min were obtained as optimal conditions for copper removal. Investigation of the isotherms indicated that the experimental data of the process were correlated with Langmuir Model. The maximum capacity of copper adsorption of Langmuir Model was 49.75 mg/g. Findings indicated that at optimal conditions, the amount of copper adsorbed from synthetic wastewater and real wastewater was 99.73% and 63%, respectively. Therefore, this method is capable of removing copper effectively and could be used to remove this metal from industrial wastewaters. © 2018 Desalination Publications. All rights reserved.

In this study, removal of an antibiotic (SDZ) from wastewater using an advanced oxidation process of persulfate (PS) in the presence of iron sulfate (S2O8 –2/Fe+2) was investigated. The operational variables such as; the effect of pH, contact time, iron and PS ion concentrations and initial concentration of SDZ on the efficiency of SDZ removal was studied. High performance liquid chromatography (HPLC) was used for the analysis and monitoring of SDZ concentration. It was found that the highest rates of SDZ removal were found to be 95.83±1.342%, 87.15±0.929% and 69.09±0.848%, respectively, for initial SDZ concentration of 0.08, 0.2 and 0.4 mmol. The results showed that the S2O8 –2/Fe+2 system would be optimized by contact time of 60 min, pH 4 and iron to PS molar ratio of 1. Therefore, these findings would help to better apply the AOPs to remove recalcitrance pollutants such as SDZ from wastewater.

Background and Aims: The aim of this study is to clarify nitric oxide (NO)-production by spleen and the importance of spleen in malaria infection in murine model. Materials and Methods: Thirty outbred NMRI female mice were divided into four groups, Group I: No intervention (Healthy control), Group II: With splenectomy (Healthy test), Group III: No intervention, Inoculation of contaminated blood (Infected control), Group IV: With splenectomy, inoculation of contaminated blood (Infected test). The Parasitemia was counted every other day through Giemsa stain examination of animal blood. The parasitemia and survival rates, hepatosplenomegaly and body weight were recorded. After terminal anesthesia, plasma and liver/spleen suspensions were assessed by the Griess micro assay for measurement of NO-levels. Results: At the end of the experiment (on day 16), the parasitemia was 26.99±0.46 % among the group of non-splenectomized animals (Group III) compared with 31.25±0.72% among the group of splenectomized animals (Group IV). The average parasitemia among the groups at the end of the experiment was statistically significant (Group III, Group IV: p= 0.0002). Survival rate was statistically significant (p

Polymerase chain reaction followed by high resolution melting (PCR-HRM) analysis is a simple, rapid and accurate method for molecular detection of various nematode species. The objective of the present study was, for the first time, to develop a PCR-HRM assay for the detection of various animal Trichostrongylus spp. A pair of primers targeting the ITS-2 rDNA region of the Trichostrongylus spp. was designed for the development of the HRM assay. DNA samples were extracted from 30 adult worms of Trichostrongylus spp., the ITS-2-rDNA region was amplified using PCR, and the resultant products were sequenced and characterized. Afterwards, the PCR-HRM analysis was conducted to detect and discriminate Trichostrongylus spp. Molecular sequence analysis revealed that 24, 4, and 1 of the samples were T. colubriformis, T. vitrinus and T. capricola, respectively. Results from PCR-HRM indicated that complete agreement was relatively found between speciation by HRM analysis and DNA sequencing for the detection of Trichostrongylus species. The PCR-HRM analysis method developed in the present study is fast and low-cost; the method can be comparable with other molecular detection techniques, representing a reliable tool for the identification of various species within the Trichostrongylus genus.

Present strategy introduces a novel method established for the synthesis of spherical shape ErVO4/MnWO4 heterostructures by a sonochemical method. This heterostructures with optima morphology can be synthesized by changing power and time ultrasound irradiation without any capping agent. BET analysis revealed that ErVO4/MnWO4 prepared in the presence of ultrasonic procedure has 75 times specific surface area as much as that of those was produced in the absence of ultrasonic rays. A variety of analyses (i.e., BET, XRD, TEM, EDS, FT-IR, and SEM) were applied for characterization of the ErVO4/MnWO4. Next, a selective and sensitive nanostructured sensor based on ErVO4/MnWO4 nanocomposite modified carbon paste electrode (ErVO4/MnWO4/CPE) was constructed for electrochemical detection of tyrosine (Tyr). The electrochemical characterizations were performed using cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS) and differential pulse voltammetry (DPV). Compared with the unmodified CPE, the oxidation peak current was significantly enhanced for Tyr. The impact of effective parameters on voltammetric response of Tyr was analyzed with design of experiments (DOE) and response surface methodology (RSM). Under the optimized conditions, the oxidation peak current of Tyr was linear over a range of 0.08–400.0 μM with a detection limit of 7.7 nM. Finally, the usage of the proposed method was confirmed by the recovery tests of Tyr in biological samples.

In the current era, cystic echinococcosis (CE), as larval stage of Echinococcus granulosus, is considered as a threat to human health. Scolicidal agents used in the surgery of cysts have different side effects. Therefore, the present study aimed to assess the effects of chitosan nanoparticles containing curcumin (Ch–Cu NPs) on the protoscolices of the hydatid cyst in vitro. Ch–Cu NPs were synthesized using a simple co-precipitation method and their structural and morphological properties were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), zeta analyzer, and Fourier transform infrared (FT-IR) spectroscopy. Then, the effects of different concentrations of Ch–Cu NPs (0.25, 0.05, 1, 2, and 4 mg/mL) on the fatality rate, and the length and width of protoscolices in different times (5, 10, 20, 30, and 60 min) were investigated. In addition, the SEM technique was used to evaluate the structure of the protoscolices after treatment. Based on the results, the presence of curcumin on the chitosan nanoparticles was confirmed by FT-IR analysis. Further, XRD analysis approved the crystal structure of chitosan NPs. Furthermore, the highest fatality rate was 68% in 4 mg/mL concentration of Ch–Cu NPs. The length and width of protoscolices decreased based on the high concentrations of Ch–Cu NPs, compared to the control group. Finally, Ch–Cu NPs expressed good scolicidal activities, which made them suitable to be considered as an anti-protoscolex agent.

Background: There are scant evidences between giardiasis and enterobiasis with human mal-absorption of micronutrient. Objectives: The aim of the present study was to found out the changes in the serum zinc, copper, magnesium and vitamin B12 levels in schoolchildren infected with Giardia intestinalis and Enterobius vermicularis. Patients and Methods: This case-control study was carried out among 359 children from aged 6 - 12 years old at 8 suburban public schools. Three stool examinations were done using standard techniques for identification parasitic infection. Fifty E. vermicularis and 37 G. lamblia infected individuals were enrolled as study groups. Serum levels of copper, zinc, magnesium were assessed by autoanalyzer and vitamin B12 levels were measured using gamma counter. ANOVA and paired t-test analyses were used to determine the association between infections and trace elements changes. Results: The prevalence of G. intestinalis and E. vermicularis infections were 10.3% and 13.9%, respectively. The serum zinc, copper and magnesium levels showed a significant decrease in individuals infected with G. intestinalis and E. vermicularis (P < 0.05). Mean values of Giardia positive and negative groups for copper 143.65 ± 16.51 and 176.26 ± 17.6 μg/dL, zinc 62.26 ± 16.06 and 80.66 ± 23.58 μg/dL, and magnesium 1.82 ± 0.23 and 2.01 ± 0.16 mg/dL, respectively. Mean values of Enterobius positive and negative groups for copper 145.55 ± 26.84 and 176.26 ± 17.6 μg/dL, zinc 72.7 ± 17.92 and 80.66 ± 23.58 μg/dL and magnesium 1.93 ± 0.11 and 2.01 ± 0.16 mg/dL, respectively. Conclusions: The results showed that giardiasis and enterobiasis decreased serum levels of copper, zinc and magnesium. Further studies are needed to clarify the actual mechanism governing the zinc, copper, magnesium and vitamin B12 giardiasis/enterobiasis interaction.

Problem Statement: MTBE is a common pollution of environmental and has become an issue of considerable concern in recent years. It is not readily amenable to remove MTBE by conventional techniques in water treatment. In the present study, the feasibility of the continuous aerobic biodegradation of MTBE, was evaluated in an Up- Flow Fixed Bed Reactor (UFBR). Approach: The UFBR at a constant Hydroulic Retention Time (HRT) of 24 h was used as a biological process that receives the intermediates due to partial oxidation of MTBE. The UFBR coupled to ozonation process as a survey system after a primary operation phase that was necessary for creatory of an initial microbial film on the carriers. Residual concentration of MTBE and its major degradation intermediates were measured by gas chromatography. Aqueous concentration of ozone in the reactor and ozone average concentration in off- gas were determined according to the indigo blue method. The COD reduction and BOD5 to COD ratio were selected as biodegradability indexes. Results: Results showed an effective degradation of MTBE in the coupled ozonation-UFBR continuous flow reactor of ten days of operation time. A partial degradation of MTBE in AOPs increases its biodegradation [The BOD5 to COD ratio increased from lowest (0.01) up to a maximum of 0.72] that corresponds to an ozone consumption of 0.62mg per each mg of COD initially present in the solution. The results showed when m. Mol[MTBE]o/m. Mol(o3) = 0.611, the COD removal efficiency was 89% and as this ratio increased up to 1.25, the of COD removal efficiency decreased to 80%. 46-68% removal of the COD was needed before the mixture was considered biodegradable. The highest removal rate of MTBE, 82.91 mg day-1 achieved through out the UFBR runs (87% removal efficiency, In this study, the removal efficiency of MTBE using integrated-process (ozonation followed biological treatment) was from 78.5-86.5%. In order to determine of biological removal rate of MTBE, another UFBR system used as a blank reactors. Results showed that the efficiency of the COD removal (by stripping with the biological degradation) was 5-8% which implies insignificant biological removal of MTBE without pre-ozonation. Solid produced in the proposed integrated process was 0.27-0.35 kg TSS kg-1 COD removed which is approximately in down range of conventional biological system (0.3-0.5 kg TSS kg-1COD). Conclusion: Present study showed that we can treatment of the polluted aqueous solutions to MTBE without microbial incubation used to integrated process.

Several studies have shown that exposure to Benzo(a)pyrene increases the risk of cancer. In this study several fish samples from Niger the Delta region of Nigeria were screened for the presence of Benzo(a)pyrene. The study was carried out using Gas chromatograph coupled to a mass spectrometry detector. Benzo(a)pyrenes in the samples were identified through both retention time match with authentic standards and simultaneous maximization of several major ions from GC/MS data. Perylene-d12 was used as the internal standard for quantitation. Concentration of benzo(a)pyrene in the samples ranged from 1.47 to 10.53 µg/kg which is more than WHO recommended maximum allowable concentration. Therefore this study concludes that the population is at an elevated risk of cancer of occurrence.

Aims: The aim of this study was the optimization of the SBR system for enhanced biological phosphorus and nitrogen removal. Materials And Methods: A lab-scale SBR consisting filling, pre-anoxic, anerobic, anoxic, aerobic, settling, decanting, and idle phases was proposed for simultaneous enhanced biological phosphorus and nitrogen removal (SEBPNR) from wastewater. Synthetic wastewater was used in this research. Glucose was used as a carbon source. The SBR was seeded with sludge from a local municipal wastewater treatment plant. Results: The results indicates that the lab-scale SBR was capable to remove soluble phosphorus (SP), SCOD, TCOD, and ammonia, with efficiencies of around 92%, 95%, 80%, and 85%, respectively. Optimized lab-scale SBR operational condition for SEBPNR consists of a fill (15 min), pre-anoxic (30 min), anerobic (90 min), 1st aerobic (210 min), 2nd anoxic (55 min), 2nd aerobic (10 min), settling (90 min), decant (10 min), and idle (10 min) phases. Conclusion: This study concludes that effective biological removal of phosphorus and nitrogen from wastewater using SBR occurs in sufficient HRT in the anaerobic and aerobic stages, adequate COD/TP ratios (up to 35). This system is suitable for high removal of P and N in both municipal and industrial wastewater.

Problem Statement: Polycyclic Aromatic Hydrocarbons (PAHs) are suspected toxins that accumulate in soils and sediments due to their inso lubility in water and lack of volatility. Slurry-ph ase biological treatment is one of the innovative techn ologies that involve the controlled treatment of excavated soil in a bioreactor. Due to highly soil contamination from petroleum compounds in crude oil extraction and also oil refinery sites in Iran, this research was designed based on slurry phase biotreatment to find out a solution to decontaminat ion of oil compounds polluted sites. Approach: Soil samples were collected from Tehran oil refiner y site and Bushehr oil zones. Two compositions of soils (clay and silt) were selected for slurry biot reatment experiment. Soil samples were contaminated with three rates of phenanthrene (a 3 ring PAH), 10 0, 500 and 1000 mg kg -1 and mixed with distilled water in solid concentration of 30% by weight after washing out with strong solvent (hexane) and putting in to the oven. Bacterial consortium was re vived in culture medium which consisted of Mineral Salt Medium (MSM) based on phenanthrene concentrations and ratio of C/N/P in the range of 100/10/2. Prepared soil samples were mixed with dis tilled water, nutrient and bacterial consortium together in the 250 mL glass Erlenmeyer and putted in the shaker incubator with 200 rpm revolutions and 25°C for 7 weeks (45 days). Samples were analyzed for residual phenanthrene, bacterial population every week. For statistical analysis, ge neral linear model with repeated measures (type III ) analysis was applied. Results: The concentration of 100 mg L -l of phenanthrene in clayey and silty soils reached to non detectable limit after 5 and 6 weeks, respectively. While concentration of 500 mg L -l of phenanthrene both in clayey and silty soils rea ched to non detectable limit after 6 weeks. But concentration of 1000 mg L -l both in clayey and silty soil samples has not met this limitation after 7 weeks. Due to presence of Pseudomonas strains in clayey soil samples and their ability i n breaking down of benzene rings, the removal efficiency of ph enanthrene in our slurry bioreactor in clayey soil was a little more than silty soil samples over time . There was a significance relationship between ini tial concentrations of phenanthrene and type of soil wit h time of biotreatment (p