Iranian Journal of

Background and Objectives: Nemone Tehran Poultry Slaughterhouse having an area of 13000 m² is located at District 3, Region 5 of Tehran Municipality and in Morad Abad Quarter .This study aimed at analysis the environmental impacts of the abovementioned slaughterhouse. For this purpose, we applied analytical hierarchy process (AHP) as one of the multiple criteria decision making methods (MCDM). Materials and Method: First, we determined the criteria and options required through analyzing the project impacts. Then, for final validity of criteria, we used experts questionnaire. Special vector technique through using the Expert Choice software was used in order to set priorities for criteria and options. Results: Analysis of the slaughterhouse effluent indicated that it can neither be discharged into the surface water and well nor suitable for irrigation and agricultural purposes. Noise evaluation showed that rate of noise measured is beyond the standard limits. The laboratory experiment results on air pollutants was lower than the standard level. Conclusion: The results indicated that from the pollution perspective in the slaughterhouse, wastewater weighted 0.497 is the primary preference and sound, air, and odour weighted 0.229, 0.136 and 0.080 are the subsequent preferences. Cultural and socioeconomical environment ranked hgiher relative to the chemical-physical environment and then biological environment. Finally, regarding to the main significant environmental problem of slaughterhouse (Wastewater), optimization of the slaughterhouse wastewater treatment system and constant monitoring of the external sewage quality is in priority.

Background and Objectives: In the recent years, we confront to harmful effects of toxins such as herbicides on aquatic species due to irregular consumption of these compounds in agricultural operations and drainage of them to water ecosystems. In the present study, the effect of 2,4-D + MCPA “the frequently used herbicide in Kurdistan province” was assessed on the hematological parameters and liver enzymes in rainbow trout as the main aquatic species farmed in this area. Materials and Methods: After determination of LC50 using Probit model, 60 healthy trout fish with an average weight of 97 g were divided into two groups. The first group was considered as control and in the second treatment group, 1 cc/L herbicide (equivalent to 360 mg/L 2,4-D + 315 mg/L MCPA) was used. After 72 hours, hematology parameters including total number of red and white blood cells, differential count of white blood cells, hematocrit, and serum levels of ALT and AST enzymes were measured. Results: The values of blood tests including leukocytes, monocytes, and eosinophils in the toxin group was significantly increased in comparison with control group, whereas, the values of lymphocytes, erythrocytes and hematocrit were significantly decreased in toxin group compared with the control (p<0.05). There was no difference between the level of neutrophils in the treatment and control groups. The levels of liver enzymes, ALT and AST, in the treatment group increased significantly compared with the control group (P<0.05). The mortality rate after of 72 hours was 25% in the group treated with the toxin. Conclusions: Erythrocytes and hematocrit amounts of blood in rainbow trout were decreased due to exposure to 2,4-D + MCPA herbicide that eventually leads to oxygen deficiency and inefficient blood supply. The contact of red blood cells and hematopoietic tissues to toxin and destruction of them are led to loss of the cells in the blood. On the other hand, liver, kidney and gills autopsy of the wasted fish and the increasing of liver enzymes in the blood and tissues showed that exposure to the toxin lead to damages in fish blood cells and tissues.

Background & Objectives: Listeria bacterium resists to the sludge digestion conditions and Listeria monocytogenes is the most important of them. Sludge produced in the north Isfahan wastewater treatment plant is stabilized by anaerobic digesters and is used for fertilizing agricultural lands after drying in the sludge drying beds. Based on the importance of the subject, the objective of this study was evaluation of sludge processing units efficiency, particularly anaerobic sludge digestion for reduction or removal of Listeria. Materials and Methods: In this descriptive study, samples were collected weekly from sludge processing units 13 times in north Isfahan wastewater treatment plant according to standard methods over three months. Listeria bacteria were enumerated and isolated by triple-tube fermentation method and U.S Department of Agriculture method respectively. Isolated Listeria were confirmed by phenotypic method and then bacterial species were diagnosed differentially by biochemical carbohydrate fermentation and CAMP test. Results: Contamination of raw, stabilized and dried sludge at least to one of L. Monocytogenes, L. Innocua and L. Seeligeri species was 100, 92.3 and 53.8 percent respectively. Anaerobic sludge digesters efficiency to remove L. Monocytogenes, L. Innocua and L. Seeligeri species was determined 64.7, 39.72, and 100 percent while the efficiency of drying sludge beds for L. monocytogenes and L.innocua species removal was 73.4 and 96.68 percent respectively. Conclusion: Listeria monocytogenes is more resistant than other identified species against the sludge processing conditions. Thus, the use of sludge as fertilizer can cause the spread of this bacterium in the environment and agricultural products pollution.

Background and Objectives: Doogh is considered as one of the traditional drink in Iran and other nations like Eastern Europe, Middle East and Asia. In the past the “doogh” was applied to a product which remained after dilution of full fat yoghurt with water and fat separation using the musk. Nowadays Doogh has have physical, chemical, physico-chemical, microbial and sensory characteristics and standards. In this study the microbial quality of four famous brands produced in Iran was assessed. Materials and Methods: This is a cross-sectional study. Totally, 126 samples were selected from the foodstuff suppliers using random sampling .In order to determine Staphylococcus aureus, Baird Parker Agar (recognition test) and coagulase test (confirmation test) were used. Results: The results were analyzed using SPSS, and T-Test and one way ANOVA were performed. The results showed that in view of contamination there is Significant differences between the months, the brands and the types of doogh (p<0.05). Conclusion: According to the results and due to probable presence of Entrotoxin, the analyzed brands can be potent risk to consumer’s health.

Background: FMEA is one of the best known system safety techniques widely used as an identification tool. The purpose of this study was to apply FMEA method to identify and assess the risks posed by power lines in a residential area is Hasyrabad, Ahwaz. Materials and Methods: First, we identified the power line process and the equipment involved. Later, we determined the failure modes of equipment, which leads to the risk in the area studied. In order to measure the magnetic field lines, we used 3D EMF TESTER. Risks identified were scored based on the FMEA and for each case we calculated RPN. Then, with the help of SPSS software, we calculated level of risk and the cases identified were prioritized and analyzed based on the risk level. Results: The highest RPN values were associated with health risks and all risks involved in this group are at emergency conditions. It was revealed that wires (loss of privacy) and power transmission line (non-compliance with privacy standards) had highest value (RPN 360) and disconnect switch had lowest value (RPN 60). Conclusion: Due to the high risk in most cases, control measures were proposed based on the expertise in the safety-related equipment, training operators, and regulatory measures in order to reduce the level of risk.

Background and Objectives: Reuse of treated wastewater in agriculture is becoming more attractive due to the growing demand for water, particularly in arid and semi-arid regions like Iran.In some areas, industrial wastewaters distribute arsenic in the water and vegetables, among the other plants, are mainly irrigated by municipal and industrial wastewater. This study aimed to evaluate the outcome of radish irrigation using water contaminated with arsenic and zinc and to measure the zinc concentration in the edible parts of radish plant. Materials and Methods: The experiments were designed in the form of a factorial completely randomized design with three replications in which radishes were planted in pots about five kilograms. Arsenic concentration at four levels (0, 100,300 and 600 µg/l) and zinc concentration at three levels (0, 10, and 50 mg/l) were added to the irrigation water. The pots were equally irrigated once every 3 to 4 days. After harvesting and laboratory operations, zinc concentration was measured using atomic absorption spectroscopy. Results: The study indicated that zinc concentration in radish tubers is correlated with the concentration of zinc in water. The results of the analysis of variance table for the effect of zinc and arsenic-contaminated irrigation water on zinc concentration in radish roots, tubers and leafs show only one treatment (zinc concentration in water) on the property is significant at 5 and 1%. The results of the comparison table revealed that Zn uptake was decreased with increasing arsenic up to 300 µg/l. Conclusion: It was found that zinc concentration in radish roots, tubers, and leafs is correlated with the concentration of zinc in water. Moreover, there was a competition between the absorption of zinc and arsenic in plants. With increasing arsenic in irrigation water, transition of Zn was reduced to aerial part.

Background and Objectives: Cadmium can enter water resources through the industrial wastewater. It could cause intensivly damages to the liver and kidney of humans. Magnetic iron nanoparticles are used to control and eliminate heavy metals from industrial effluents through the mechanisms of adsorption, ion exchange and electrostatic forces. The aim of this study was to evaluate the efficiency of magnetic nanoparticles for adsorption of cadmium. Methods: The magnetite nanoparticles were prepared by co-precipitation method through the addition of bivalent and trivalent iron chloride under alkaline conditions. Characteristics of nanoparticles including particles structure, composition and size were determined using analytical devices such as XRD, SEM, and FT-IR. For optimization of adsorption process of cadmium, some parameters such as pH, contact time, initial concentration of cadmium, nanoparticles concentration, and temperature were studied under different conditions. Results: It was found that 95% of cadmium could be removedAt pH &ge 5.6, 10 mg/L initial cadmium concentration, a dose of 1 mg synthesized magnetite nanoparticles, 10 minutes contact time, and 200 rpm mixing rate at 25 °C. The isotherm of adsorption follows the Langmuir model (R2 < 0.995). Maximum capacity of cadmium adsorption was found to be 20.41 mg/g. Conclusion: Magnetite nanoparticles exhibit high capability for removal of cadmium. The nanoparticles synthesized could be used at industrial scale because of having the magnetic property, which make them easily recovered from aqueous solution through applying a magnetic field.

Background and Objectives: The use of surfactants enhance the bioavailability of nonbiodegradable contaminants such as PAHs. Biosurfactants are more environmental friendly. In this study the ability of removing phenenthrene from soil by biosurfactant was assessed and compared with that of chemical surfactant. Materials and Methods: A soil sample free of any organic or microbial contamination was artificially spiked with phenanthrene at two concentrations. Then, mineral salt medium at constant concentration of chemical surfactant TritonX-100 and rhamnolipid MR01biosurfactant was added to it in order to have the proportion of 10% w:v (soil:water). A microbial consortium with a potential of phenanthrene biodegradation was inoculated to the soil slurry in two densities (OD=1 and 2) and then it was aerated on a shaker. After eight weeks, the residual concentration of phenanthrene in the soil was extracted by ultrasonic and was analyzed using HPLC. MPN test was used for measuring microbial population. This study was conducted based on the two level full factorial design of experiment. Results: It was found that chemical surfactant exhibited higher PHE removal efficiency than the biosurfactant. Using 120 mg/L of TritonX-100 and rhamnolipid, the PHE removal for the soil contaminated with 50 mg PHE/kg dry soil was 98.5 and 88.7% respectively, while the removal efficieny was decreased to 87 and 76% respectively for the soil contaminated with 300 mg PHE/kg. In the absence of surfactant, the removal efficiency at concentrations of 50 and 300 mg PHE/kg dry soil was achieved 60.76 and 51% respectively. The phenanthrene removal efficiency in OD=2 was more higher than OD=1. In the presence of rhamnolipid, the maximum microbial populations was observed in the second week, while it decreased in the presence of TritonX-100. Conclusion: Use of biosurfactants can be considered as a suitable option in low level pollutant sites. Chemical surfactants as ex-situ has achieved more satisfactory results in high level contaminant sites.

Background & Objectives: In recent years, enterance of oil contaminants especially polycyclic aromatic hydrocarbons (PAHs) to Anzali Wetland, has seriously threatened organisms life. Therefore, the current study was conducted to determine and compare concentration of PAH compounds with multiple sediment quality assessment indice to evaluate the ecological toxicity of surface sediments of Anzali Wetland and present appropriate management strategy. Materials & Methods: We randomly collected 22 surface sediment samples each sample was dried and extracted based on the soxhlet method. Then during two-step of column chromatography the PAH compounds were separated and analyzed by gas chromatography equipped with a mass spectrometry detector (GC-MS). Results: Total concentrations of these compounds ranged from 212 to 2674 ng g-1 d.w. with the mean of 907 ng g-1 d.w. The highest concentrations of PAHs was reported from stations (3-1 and 4-1) located in the vicinity of urban areas with shipping activities. In comparison with sediment quality guidelines (SQGs) used in this study, the concentrations of most PAH compounds in the majority of stations situated in low range values of adverse biological effects. Only in a few stations (3-1, 3-2 and 5-3), the concentrations of some of PAH compounds exceeded the low range of adverse biological effects. Conclusion: In comparison with sediment quality guidelines (SQGs) used in this study, the concentrations of most PAH compounds in Anzali Wetland rarely lead to adverse biological effects. However, concentrations of some of these compounds can cause acute toxic effects. Therefore, further studies including toxicity and bioaccumulation tests and survey of benthic community composition, especially in areas exceeded SQGs are essential for proper management.

Background and Objective: Electrochemical methods as one of the advanced oxidation processes (AOPs), have been applied effectively to degrade recalcitrant organics in aqueous solutions. In the present work, the performance of electro-Fenton (EF) method using iron electrodes on the degradation of phenol was studied. Materials and Methods: In this study, a lab-scale EF batch reactor equipped with four electrodes and a DC power supply was used for removing phenol. The effect of operating parameters such as pH, voltage, H₂O₂ and initial phenol concentration and operating time were evaluated. We added H₂O₂ manually to the reactor while iron anode electrode was applied as a ferrous ion source. Results: It was found that initial pH of the solution, initial H₂O₂ concentration, applied voltages were highly effective on the phenol removal efficiency in this process, so that 87% of phenol after 15 min of reaction at pH=3.0, voltage 26 V and H₂O₂ 100 mg/L was removed. Phenol removal efficiency decreased with increasing pH, so that at pH 10, after 15 min, efficiency was 11%. To remove 99.99% phenol at pH 3, 100 mg/L concentration of H₂O₂ and voltage 26 V for 60 min was required. Conclusion: Electro-Fenton process using iron electrodes for phenol degradation and remediation of wastewater could be a promising process.

Background and objectives: Because of problems dealing with bioremediation including being time consuming, low efficiency and toxicity to biota, application of advanced oxidation processes with higher efficiency and shorter remediation time have been considered for removal of hydrophobic hydrocarbons from contaminated soils. A great interest has been directed to Fenton oxidation because of its simplicity and high oxidation potential. The objective of this study was to determine the Fenton-like oxidation efficiency for pyrene removal from soil using iron nano oxides and Fe²⁺. Material and Methods: The H₂O₂/Fe molar ratios of unadjusted with native Fe content of soil, 10, and 20 H2O2 concentrations of 0 – 500 mM pH 3, 5, and 7 and soil samples containing Fe²⁺, native iron and iron nano oxides were investigated for removal of 100 mg/kg pyrene according to Taguchi experimental design. Results: Fe²⁺, H₂O₂/Fe molar ratio of 20, pH 3 and H₂O₂ concentration of 500 mM were determined as optimum conditions. Under optimum conditions, S/N ratio increased to 39.322 and the pyrne removal reached to 86 % for Fe²⁺ and 83 % for Fe³⁺ respectively, after 2 hours of reaction time and pH 3. Conclusion: Fenton oxidation using iron nano oxides under defined optimum conditions and neutral pH, can be a suitable alternative to conventional Fenton for remediation of soils contaminated with pyrene.

Background & Objectives: Entering LAS through the wastewater plant’s effluent to water resources causes taste and odor changes, aquatics death, oxygen transfer limitation, and disorders in water treatment processes. Therefore, the study objective was to determine optimum conditions for fenton oxidation process to remove linear alkyl benzene sulfonate from aqueous environments using taguchi method and its requirement evaluation for additional treatment of Biolac effluent. Materials &Methods: LAS removal using Fenton oxidation was evaluated in a 500 mL laboratory-scale batch reactor. In order to save the costs, to determine the optimum conditions of the Fenton oxidation, 25 runs were computed using Taghuchi method by Minitab 16 software. Sampling and required tests were performed based on standard methods examination for water and wastewater. For evaluation of Biolac process sufficiency in LAS removal, biolac efficiency in Urmia Wastewater Treatment Plant was studied in 2012. Results: Based on the LAS removal and chemicals required, Minitab software (Ver. 16) recommended the optimum conditions of Fenton oxidation at 900 mg/L H2O2, 170 mg/L Ferrous ion, pH of 4, and reaction time of 20 minutes. It was found that the Fenton oxidation for LAS removal had 86.5% efficiency under optimum condithions and it was second order reaction with the rate coefficient of 0.0152 L/mg.min. Biolac process does not need any additional treatment due to meeting LAS standard in municipal wastewater treatment. Thus, this process decreased annually mean LAS from 5.28 mg/L to 0.734 mg/L in municipal wastewater. Conclusion: Although the Fenton oxidation appears as a chemical process with high efficiency in the removal of LAS, the low efficiency of COD corresponding to the LAS indicated partial decomposition of linear alkyl benzene sulfonate by Fenton oxidation.

Background and Objectives: Bottles for packaging drinking water represent one of the most popular uses of plastic and polymer additives. Recently, public concerns related to possibility of exposure to chemicals through the consumption of polyethylene terephthalate bottled water has caused great concern to consumers. Phthalate esters, as a class of these compounds, are often classified as endocrine disruptors and one of them is a possible carcinogen for human. The aim of this study was to determine the concentrations of phthalates in bottled water and to calculate the health risk of phthalates intake via consumption of bottled waters. Materials and Method: After purchasing, samples were immediately stored according to the recommended conditions (25 ºC, dark place) given on the bottle label. Migration of phthalates was investigated in PET-bottled water at different time intervals using gas chromatography–mass spectroscopy. Therefore, a phthalate exposure assessment was performed to characterize their risk to the consumer’s health via a calculated hazard quotient (HQ). Results: It seems that the duration of storage affects phthalate migration. Total increases of DEHP (811.8%), DBP (2545.2%), and BBP (832%) were observed at 12 months over the initial level before storage (bottled water immediately after production) but the level of phthalates in bottled water was always very low (<EPA:6 μg/L). Non-carcinogenic risk assessment from exposure to phthalate via consumption of bottled water was negligible in all of the subject groups (HQ<1). Furthermore, a little excess cancer risk of 9.9×10^-7 for bis (2-ethylhexyl) phthalate (DEHP) was observed.Conclusion: The research showed that the concentration of phthalates in PET-bottled water was extremely low. Consequently, based on the risk assessment results, bottled waters regarding existence of safe for consumers and they phthalates are not considered as public health issue for consumers as phthalates does not have any risk exposure for the consumers.

Background and Objectives: Reduction of released extracellular polymeric substances (EPS) during sludge dewatering is one of the main challenges in sludge treatment process. The aim of this study was to investigate the EPS quantity changes within sludge dewatering by continues ultrasonic – electrocoagulation (US – EC) reactor under different conditions and to determine the most efficient case for reducing these substances. Materials and Methods: In this study, the EPS quantity changes in supernatant were compared after undergoing different conditions of ultrasonic (frequency of 35 and 130 KHz, detention time of 3,5,10, and 30 min) and electrocoagulation (voltage of 20, 30, and 40 V, detention time of 10, 20, and 30 min) processes were compared. Results: The research found that the maximum efficiency of the US-EC reactor was achieved at a frequency of 35 KHz and detention time of 5 min for ultrasonic with voltage of 40 V and at detention time of 30 min for electrocoagulation process as under these conditions total EPS concentration reduced by 69%. Conclusion: According to the results achieved, US – EC reactor significantly reduced the released EPS in supernatant in addition to dewatering sludge.

Background and Objectives: According to the estimates of W.H.O., approximately 150000 persons are annually affected by early death of cardiovascular, respiratory disease, and lung cancer resulted from air pollution in south Asia. The short-term and long-term effects are reported as hospital admission, consulting with a physician, number of special disease, death and years of life lost (YOLL). The purpose of this paper is to discuss the effects of PM₁₀ pollution on human health. AirQ 2.2.3 (Air Quality Health Impact Assessment) Model was used to evaluate adverse health effects caused by PM₁₀ exposure in Ahvaz during 2009. Long-term exposure with suspended particulates are expressed as decreasing personal life. The prevalence of bronchitis and reduced lung function in children and adults, even at annual average concentrations of particulate matter below 20 µg/m³ (PM_2.5) and 30 µg/m³ (PM₁₀) have been observed. Major sources of emissions resulting from human intervention in particulate matter are road traffic (25-10%), stationary combustion (55-40%), and industrial processes (30-15%). Materials and Methods: First, PM₁₀ data was collected from Ahvaz Environment Protection Organization and Meteorological Organization. Then, raw data were processed by Excel software.. Finally, data processed were inputted to AirQ model. This model proved to be a valid and reliable tool to estimate the potential short-term effects of air pollution. This software is provided by the World Health Organization and is used to quantify the health effects of air pollution. This model consists of four input screens (Supplier, AQ data, Location, Parameter) and two output screens (Table, Graph). Results: The highest and lowest PM₁₀ concentration was reported for Headquarter and Naderi stations respectively. Moreover, the annual, summer, and winter means and 98 decimal of this pollutant in Ahvaz City was measured as 261, 376, 170, and 1268 µg/m³ respectively. Total death toll contributed to PM₁₀ was estimated as 1165 cases in 2009. Conclusion: Using data processing in Excel, AirQ software calculates relative risks, attributable proportion, and baseline incidence and the final output would be displayed in the form of death toll. It is noteworthy that there is no model that can estimate the effect of all pollutants together and simultaneously. In addition, it was found that the annual PM₁₀ emission mean, the summer mean, winter mean, and 98 percentile were 261, 376, 170, and 1268 µg/m³ in Ahvaz City. Cumulative number of persons for total number of deaths attributed to PM10 exposure was 1165 in 2009 Out of which, 44% has occurred in the days with concentrations lower than 250 µg/m³. It should be noted that 62% of this value is corresponded to the days with concentrations below 350 µg/m³. The total cumulative number of cardiovascular death attributed to the exposure with PM₁₀ during one year of monitoring was 612 persons. On the other hand, 52% of these cases have occurred in days with PM₁₀ levels not exceeding 300 µg/m³. Cumulative number of Hospital Admissions Respiratory Disease attributed to exposure with PM₁₀ during one year of monitoring was 1551 persons Out of which, 36 % occurred in days with PM10 levels not exceeding 200 µg/m³.

Background and Objectives: one of the most important environmental concerns is heavy metals emissions from human activities to natural ecosystems, particularly transfer to soil. The aims of this study were measured the concentrations of Cu, Zn and Cr in landfill soil and hospital waste ash of Shahrekord municipal solid waste landfill. Materials and Methods: Soil samples were collected from three sites: out of the landfill, municipal landfill and hospital landfill. In each site 2, 1, and 1 stations ware selected respectively and each sample was replicated in three times. Results: We found that there was a significant difference between concentrations of Cu, Zn and Cr in the landfills soil (95% confidence, P <0.05). Furthermore, the highest levels of Zn and Cu were detected in the hospital landfill and also for Cr in the municipal landfills. However, the concentration levels of heavy metals in all of the sites were in order as follows: Zn>Cu>Cr. Conclusion: High concentrations of metals determined in the present study represents the high application of these metals in the structure of municipal and hospital solid wastes and also their inaccurate separation. Thus, awareness about physical and chemical characteristics of municipal and hospital wastes and also the landfill soil is necessary for evaluating their effects on the soil quality and surrounding environments.

Background and Objective: Phenol and phenol derivatives in industrial wastewater are among the pollutants with priorities. The high cost and low efficiency of some routine treatment processes of industrial wastewater has limited their use. One of the new methods under consideration is, nowadays, adsorption using carbon nanotubes. This study was conducted in order to evaluate the application of alumina-coated multiwall carbon nanotubes in eliminating phenol from synthetic wastewater. Materials and Methods: This study was performed in laboratory at batch scale. Multi-wall carbon nanotubes were coated with Alumina. The concentration of phenol was determined by spectrophotometer through photometry. The effect of pH changes, dosage of adsorbent, contact time, the initial concentration of phenol, temperature, and the concentrations of different salts on the efficiency of absorption was evaluated. Then, the absorption results were described using the Langmuir and Freundlich isotherms and the synthetics of absorption. Results: It was found that absorption efficiency increased significantly by decreasing the initial concentration of phenol and pH and by increasing the carbon nanotube dosage, temperature, and contact time. On the other hand, the maximum elimination of phenol from the solution (98.86%) occurred at 4 mg/l phenol concentration, under acidic conditions (pH=3), at adsorbent dosage of 0.05 g/l, at temperature of 45°C, and contact time of 10 min. Evaluation of the regressions isotherms showed that the process follows the Langmuir model and second-degree synthetic absorption. Conclusion: The high efficacy (98%) of the adsorption process in this study showed that alumina-coated multiwall carbon nanotubes have a good capability in eliminating phenol and can be used as an appropriate and new method for eliminating phenol and its derivatives from wastewater.

Background and Objective: Significant increase in population and as a result, the production of excessive waste has recently made attention to municipal solid waste management a necessary issue. The objective of this study was to use matrix-based EIA process in order to determine best waste management option in Birjand City and to suggest appropriate solutions to managers and planners of this city. Materials and Methods: Assessing the environmental impacts of waste management options was done using Iranian Leopold Matrix. Through this method, the environmental impacts of waste management options were determined in the Birjand City. The options were Open dumping, Recycling, Composting, and Sanitary damping. Results: The results indicated that Open dumping with a final score of -3.06 had the highest environmental impact and was introduced as the fourth preference. In addition, composting with final score of -2.34 has the lowest environmental impact compared with other options. Conclusion: About 76.95% of the composition of municipal solid waste of Birjand City is household waste therefore, putrescible organic materials are the predominant waste. Thus, according to the results of the Iranian Leopold matrix method, composting option was introduced as the first priority and the most logical option for waste management in the Birjand City.

Background and Objective: The concentration of nitrate, factors affecting the balance sheet, and the changes in an aquifer is of utmost importance. Because modeling is an efficient method to predict the concentration of ions in water resources, in this study using lumped-parameter model and Monte Carlo simulation model, the nitrate concentrations in groundwater resources of Qazvin Plain were estimated and analyzed.

Materials and Methods: A total of 19 wells in different climates of saline watershed in Qazvin Plain were selected and entry and exit routes of nitrate to these sources were analyzed using lumped-parameter model.  Finally, Monte Carlo simulation was used to determine the probability of the estimated nitrate concentration in aquifer.

Results: Application of lumped-parameter model for a part of a part of groundwater resources in Qazvin Plain watershed predicted the nitrate concentration in the range of 8.12 to 15.94 mg/l.   The maximum concentration was estimated in cold-dry climate with 12.8±0.04 mg/L. Moreover, it was found that the difference between the estimated nitrate concentration and factors affecting its concentration in different climates was significant (p<0.05).

Conclusion: Despite the predicted concentrations of nitrate in the study area were in accordance with the Iran national standard for drinking purposes, the cumulative probability of Monte Carlo simulation showed that the possible violation of nitrate from the safe limit of 10 mg/l in the study area is 90% (p = 0.005).

Background and Objectives: Organophosphate pesticides are used most commonly for domestic, commercial, and agricultural purposes and have been found to be highly toxic. In essence, bioremediation has become one of the most important tools for removing these compounds in the environment, considering its higher efficiency when compared with the physicochemical methods.

Materials and Methods: The biodegradation efficiency of two bacterial strains (i.e. Serratia marcescens BNA1 and Pseudomonas aeruginosa BNA2) were assessed. In order to evaluate Malathion biodegradation, each sample was cultured on mineral salts medium containing Malathion as a sole carbon source. Malathion biodegradation efficiency of the strains was monitored in different culture media. The ability of bacterial isolates to degrade Malathion was studied using gas chromatography.

Results: Serratia marcescens BNA1 and Pseudomonas aeruginosa BNA2 were able to degrade Malathion. Biodegradation percentage in different treatments recorded were: BNA1+Ma (33.88%), BNA2+MA (26.45%), BNA1+BNA2+Ma (46/96%), BNA1+Ma+Tween (61.05%), BNA2+Ma+Tween (40.17%), and BNA1+BNA2+Ma+ Tween (67.79%).

Conclusion: It could be speculated that the best degradation efficiency can be yielded using mixture of strains plus a surfactant. The results of this study can be used in the bioremediation of Malathion contaminate soil after doing the pilot experiments.