Data on bioassay of toxicity reduction of treated textile wastewater by using nanophotocatalytic process by Daphnia magna.

Practicability and possibility of photocatalytic degradation of Ro16 textile dye and the actual wastewater of textile were studied on pilot scale. The amount of reduction in solution toxicity was studied and assessed by the application of a bioassay using Daphnia magna. The solution toxicity at the beginning of the process has an increasing procedure and this is caused by the intermediate products that are produced during the photocatalytic process from the mother compounds, and are more toxic compared to them, and their toxicity declines at the end of the process with the completion of mineralization. The procedure of toxicity increase and its decrease in the course of photocatalytic process has a direct relation with the amount of mineralization.

An investigation of desalination by nanofiltration, reverse osmosis and integrated (hybrid NF/RO) membranes employed in brackish water treatment.

BACKGROUND: As an appropriate tool, membrane process is used for desalination of brackish water, in the production of drinking water. The present study aims to investigate desalination processes of brackish water of Qom Province in Iran. METHODS: This study was carried out at the central laboratory of Water and Wastewater Company of the studied area. To this aim, membrane processes, including nanofiltration (NF) and reverse osmosis (RO), separately and also their hybrid process were applied. Moreover, water physical and chemical parameters, including salinity, total dissolved solids (TDS), electric conductivity (EC), Na+1 and Cl-1 were also measured. Afterward, the rejection percent of each parameter was investigated and compared using nanofiltration and reverse osmosis separately and also by their hybrid process. The treatment process was performed by Luna domestic desalination device, which its membrane was replaced by two NF90 and TW30 membranes for nanofiltration and reverse osmosis processes, respectively. All collected brackish water samples were fed through membranes NF90-2540, TW30-1821-100(RO) and Hybrid (NF/RO) which were installed on desalination household scale pilot (Luna water 100GPD). Then, to study the effects of pressure on permeable quality of membranes, the simulation software model ROSA was applied. RESULTS: Results showed that percent of the salinity rejection was recorded as 50.21%; 72.82 and 78.56% in NF, RO and hybrid processes, respectively. During the study, in order to simulate the performance of nanofiltartion, reverse osmosis and hybrid by pressure drive, reverse osmosis system analysis (ROSA) model was applied. The experiments were conducted at performance three methods of desalination to remove physic-chemical parameters as percentage of rejections in the pilot plant are: in the NF system the salinity 50.21, TDS 43.41, EC 43.62, Cl 21.1, Na 36.15, and in the RO membrane the salinity 72.02, TDS 60.26, EC 60.33, Cl 43.08, Na 54.41. Also in case of the rejection in hybrid system of those parameters and ions included salinity 78.65, TDS 76.52, EC 76.42, Cl 63.95, and Na 70.91. CONCLUSIONS: Comparing rejection percent in three above-mentioned methods, it could be concluded that, in reverse osmosis process, ions and non-ion parameters rejection ability were rather better than nanofiltration process, and also better in hybrid compared to reverse osmosis process. The results reported in this paper indicate that the integration of membrane nanofiltration with reverse osmosis (hybrid NF/RO) can be completed by each other probably to remove salinity, TDS, EC, Cl, and Na.

Tinidazole removal from aqueous solution by sonolysis in the presence of hydrogen peroxide.

Aqueous solutions of the tinidazole (TNZ) have been treated by applying the combination of ultrasound irradiation and H2O2. Based on the results, the maximum removal efficiency of 75% was achieved under the optimum operating conditions (pH 3, 120 kHz frequency, 333 mM/L of H2O2 and 150 min of operating time) while, under the same conditions the minimum removal efficiency was found to be 8.5 by ultrasound radiation in the absence of H2O2. The results also revealed that the degradation of TNZ was enhanced with decreasing both TNZ initial concentrations and pH. Furthermore, TNZ removal efficiency in the case of actual wastewater was less than of synthetic wastewater (75% and 68% of synthetic and actual, respectively). According to the chromatographic analyses, no harmful intermediate compounds were observed. The chemical oxygen demand analysis (65% reduction) confirmed our findings.

Fluoride concentration in potable groundwater in rural areas of Khaf city, Razavi Khorasan Province, northeastern Iran.

Long-term exposure to high concentrations of fluoride is associated with several adverse effects on human including dental and skeletal fluorosis. We studied all the groundwater wells located in rural areas of Khaf city, Razavi Province, northeastern Iran between 2009 and 2010. Fluoride concentration of water samples was measured by SPADNS method. We found that in rural areas the fluoride concentration ranged from 0.11 to 3.59 ppm-the level was less than the permissible limit in 31% of studied samples, higher than the permissible limit in 4% of the samples, and within the optimum limit of 1 to 1.5 ppm in 65% of water samples.

Field efficacy of expanded polystyrene and shredded waste polystyrene beads for mosquito control in artificial pools and field trials, Islamic Republic of Iran.

Concerns about traditional chemical pesticides has led to increasing research into novel mosquito control methods. This study compared the effectiveness of 2 different types of polystyrene beads for control of mosquito larvae in south-east Islamic Republic of Iran. Simulated field trials were done in artificial pools and field trials were carried out in 2 villages in an indigenous malaria area using WHO-recommended methods. Application of expanded polystyrene beads or shredded, waste polystyrene chips to pool surfaces produced a significant difference between pre-treatment and post-treatment density of mosquitoes (86% and 78% reduction respectively 2 weeks after treatment). There was no significant difference between the efficacy of the 2 types of material. The use of polystyrene beads as a component of integrated vector management with other supportive measures could assist in the control of mosquito-borne diseases in the Islamic Republic of Iran and neighbouring countries.

Field efficacy of expanded polystyrene and shredded waste polystyrene beads for mosquito control in artificial pools and field trials, Islamic Republic of Iran

Concerns about traditional chemical pesticides has led to increasing research into novel mosquito control methods. This study compared the effectiveness of 2 different types of polystyrene beads for control of mosquito larvae in south-east Islamic Republic of Iran. Simulated field trials were done in artificial pools and field trials were carried out in 2 villages in an indigenous malaria area using WHO-recommended methods. Application of expanded polystyrene beads or shredded, waste polystyrene chips to pool surfaces produced a significant difference between pre-treatment and post-treatment density of mosquitoes [86% and 78% reduction respectively 2 weeks after treatment]. There was no significant difference between the efficacy of the 2 types of material. The use of polystyrene beads as a component of integrated vector management with other supportive measures could assist in the control of mosquito-borne diseases in the Islamic Republic of Iran and neighbouring countries

Modeling of nonylphenol degradation by photo-nanocatalytic process via multivariate approach.

Modeling of photocatalytic degradation of nonylphenol (NP), an endocrine disrupter and toxic compound, has been investigated in synthetic aqueous solutions containing ZnO nanoparticles as semiconductor using multivariate approach. In this regard, a full factorial experimental design was performed in order to study the main variables affecting the degradation process as well as their most significant interactions. Initial NP concentrations ([NP](0)) of 0.454-9.08 µM, were treated with UV-vis/ZnO using different pH and nanocatalyst loading rates. Effect of experimental parameters on the NP degradation rate constant was established by the response surface plots. The degradation rate constant decreased with an increase in the initial concentration of NP, while it increased with ZnO loading until a concentration of 0.5 g L(-1). The rate constant increases with increase in pH up to 10, after which a significant decrease is observed. The results showed that most influential factors on NP degradation constant are the [NP](0), pH of reaction media, and ZnO loading rate, and the most significant interaction is [NP]-pH. Finally, two mathematical models have been proposed to estimate NP degradation rate constant (k) on the basis of the significant variables and interactions. Predicted results of models showed good agreement with the experimental data (R(2) = 0.83 and 0.93).

Survey of dissolved air flotation system efficiency for reduce of pollution of vegetable oil industry wastewater.

The aim of this research was to sudy the reduction of pollution of vegetable oil manufacturing wastewater with DAF system. At first phase of this examination, the optimum dosage of the coagulants was determined. The coagulants that used in this study were Alum and Ferric Chloride. The second phase was flotation in this series of examinations, oil, COD, total solid, volatile solid, fixed solid and suspended solid measured in raw wastewater and the effluent of the DAF pilot. Optimum value of pH for alum and ferric chloride obtained 7.5 and 5.5, respectively. Optimum dosage for these obtained 30 and 32 mg L(-1) in this research. Mean removal for the parameters ofoil, COD, total solid, volatile solid, fixed solid and suspended solid obtained 75.85, 78.27, 77.32, 82.47, 73.52 and 85.53%, respectively. With pressure rising from 3 to 4 and 5 atm removing rate of COD, total solid, volatile solid, fixed solid parameters reduced, but oil and suspended solid have increase. In addition, following increase of flotation time up to 120 sec all of the measured parameters have increase in removing rate. Optimum A/S for removal of COD, total solid, volatile solid, fixed solid parameters obtained 0.001 and for oil and suspended solid obtained 0.0015.

Determination of aluminum and zinc in Iranian consumed tea.

To determine aluminum and zinc in Iranian consumed tea, 31 tea samples were analysed for Al and Zn concentration of tea leaves and tea infusion. The results show that average concentration of Al and Zn in tea leaves was 326 and 50.7 mg. Kg(-1) respectively in this regard Nemoneh and Shahrzad show the highest and lowest concentration respectively in term of Al, also Debsh and Alkozi follow same situation in Zn concentration. Also the solubility of metals in the first infusion was significantly (Al, Zn: P < 0.01) higher than the second infusion and the solubility in the second infusion was also significantly higher than the third infusion (Al: P < 0.01; Zn: P < 0.05). Al leachate in the first infusion (2 min) for Mosama and Seilan tea was highest and lowest respectively. Also in the second and third infusion (5 and 10 min) Golkis and Nemoneh tea show the highest and lowest figures respectively. On the other hand, data from Zn transfer in tea infusion in the first infusion show that Mosama and Ahmad Atry tea have the highest and lowest leachate percentage respectively, while in the second and third infusion Mosama and Golkis tea follow the same situation. Calculation of percentage 'available' Al and Zn to the human system showed that 1 l of tea can provide 37.2% of the daily dietary intake of Al, the percentage 'available' for absorption in the intestine is only 1.78% for overall mean Al concentration. Also daily dietary intake of Zn was 2.13% while percentage available for absorption in the intestine was 0.72%.

Study of natural organic matter fractions in water sources of Tehran.

Natural Organic Matters (NOMs) are abundant in natural water resources and in many ways may affect the unit operations in water treatment. Although, NOMs are considered harmless but they have been recognized disinfection by-products precursors (DBP(s)) during the chlorination process. Formation of DBP(s) highly depends on the composition and concentration of NOM, which can be broadly divided into two fractions of hydrophobic (humic) and hydrophilic (non-humic) substances. The objective of this study was to determine Natural organic matter and its fractions concentration in the surface water sources of Tehran. Water sampling was conducted monthly between May to July 2006 in three rivers Lar, Jajrood and Karaj as the main drinking water supplying sources in Tehran. Quantitative parameters of pH, EC, UV254 and DOC were studied based on to standard methods. The XAD-7 resin method was used for fractionation of NOM. Results showed that NOM concentrations in Lar, Jajrood and Karaj rivers were 8.53, 12.9 and 11.3 mg L(-1), respectively. The HPO (hydrophobic) fraction was predominant compared to the HPI (hydrophilic) fraction in the all of water samples. The mean of total percent of HPO and HPI fractions were about 57 and 43%, respectively. Since the hydrophobic NOM fraction exhibits higher trihalomethane formation potential (THMFP) than hydrophilic NOM, Tehran water chlorination exhibits higher THMFP than haloacetic acid formation potential (HAAFP). The information obtained from this study may be further employed in the design of the control technique and management strategies for the water treatment plant, especially for DBP(s) reduction.

The treatment of wastewater containing crude oil with aerated submerged fixed-film reactor.

An aerated submerged fixed-film (ASFF) bioreactor was developed to treat an artificial wastewater based on crude oil. Bee-Cell 2000 was used as support media having porosity of 87% and a specific surface area of 650 m2 m(-3). The system was able to achieve 70.87-93.12% removal efficiencies of Chemical Oxygen Demand (COD) in the organic loading rate range of 1.310 to 15.797 g COD m(-2) day(-1). Data gained exhibited that the effluent COD concentration ranged between 68.68 and 292.60 mg L(-1) at organic loadings experienced. Therefore, an ASFF process showed that it was feasible to treat high oily wastewater in order to meet the discharge standards.

Helminth eggs in raw and treated wastewater in the Islamic Republic of Iran.

To assess the type and load of helminths in wastewater and the quality of treatment, we examined the raw and treated wastewater of 8 wastewater treatment plants (WTP) in Tehran and 2 in Isfahan for the presence of helminth eggs during 2002-2003. Wastewater samples obtained from both inlet and effluent of each treatment plant were examined on several occasions using the modified Bailenger method. Untreated entry wastewater in Tehran WTPs contained a larger variety of helminth eggs than those of Isfahan, as well as higher total egg counts. The helminths identified in the influent of Tehran included Ascaris lumbricoides, hookworms, Enterobius vermicularis, Trichostrongylus spp., Taenia spp., Hymenolepis nana and Dicrocoelium dendriticum, while in Isfahan only A. lumbricoides, Trichostriogylus and H. nana were isolated. After treatment, the number of eggs/L fell to < or = 1 egg/L.

Helminth eggs in raw and treated wastewater in the Islamic Republic of Iran

To assess the type and load of helminths in wastewater and the quality of treatment, we examined the raw and treated wastewater of 8 wastewater treatment plants [WTP] in Tehran and 2 in Isfahan for the presence of helminth eggs during 2002-2003. Wastewater samples obtained from both inlet and effluent of each treatment plant were examined on several occasions using the modified Bailenger method. Untreated entry wastewater in Tehran WTPs contained a larger variety of helminth eggs than those of Isfahan, as well as higher total egg counts. The helminths identified in the influent of Tehran included Ascaris lumbricoides, hookworms, Enterobius vermicularis, Trichostrongylus spp., Taenia spp., Hymenolepis nana and Dicrocoelium dendriticum, while in Isfahan only A. lumbricoides, Trichostriogylus and H. nana were isolated. After treatment, the number of eggs/L fell to </= 1 egg/L

Human and animal fascioliasis in Mazandaran province, northern Iran.

The fascioliasis situation in humans and livestock of Iranian Mazandaran is analysed for the first time. Coprological studies showed 7.3% and 25.4% global prevalences in sheep and cattle, respectively. Studies in slaughterhouses indicate that sheep and cattle may be the main reservoir species, buffaloes may play local roles in the transmission, and goats and horses probably only participate sporadically. Morphometric studies by computer image analysis showed that forms intermediate between Fasciola hepatica and F. gigantica appear in addition to both species. A total of 107 infected humans were diagnosed during the 1999-2002 period, which suggests that fascioliasis may be widespread. The absence of differences in human fascioliasis among gender and age groups differs from other human endemic areas. Both human and animal infections show marked differences between western and eastern Mazandaran. Traditions in herbal condiments for human consumption, methods of animal husbandry and annual rainfall may explain the higher prevalences in western Mazandaran.