فصلنامه سلامت و محیط زیست
سال دهم شماره 3 (پیاپی 37، پاییز 1396)

In countries such as Iran that are facing with water scarcity and water crisis, paying attention to the quantity, quality and sustainable use of water resources is very significant. Petrochemical processes discharge pollutants into the environment, contaminating surface water resources. Therefore, treatment of the wastewater of these industries is necessary. Due to the capabilities of AHP process such as generalization, consideration of various parameters, multi-dimensional selection and quantifying the qualitative parameters by experts, the current study was carried out to select the best wastewater treatment alternative for HDPE plant of petrochemical research and technology company-Arak center based on AHP in 2016.
In this study, both sequencing batch reactors (SBR) and extended aeration activated sludge (EAAS) systems based on environmental, technical-functional, economic and management criteria's according to the expert's opinion were weighted. Then, the paired comparisons of the selected wastewater treatment systems for each criterion were developed. Finally, the results were analyzed to select the best wastewater treatment systems for HDPE unit of petrochemical industries using Expert Choice 11 Software.
The results showed that the SBR wastewater treatment system was the best method for the wastewater treatment of HDPE plant of petrochemical research and technology company-Arak center as compared with the ESSA system. Also, consistency ratio was ranged from 0 to 0.10 in all emphases. Based on the results of the sensitivity analysis, the SBR system had the highest priority of economic and environmental criteria. The ESSA system had the highest priority of technical-functional and management criteria.
Based on the results, although ESSA method requires more maintainance and management than the SBR method, due to increasing requirement for the compliance of the output effluent quality with permissible limits and the need for less land for the establishment of the treatment plant, the SBR method was selected to be the most suitable process for HDPE plant wastewater treatment.

one of the steps in water treatment to protect microbial quality of water network is disinfection. Chlorine is one of disinfectants. It is necessary to maintain Free Residual Chlorine (FRC) between minimum and maximum throughout the distribution system in accordance to health standards. This study was aimed to optimize Chlorine dosage in water distribution networks using GANetXL model.
In this paper for the first time using an add-in called GANetXL optimization that uses a genetic algorithm, the Chlorine injection was optimized in a reference network based on dynamic connection to EPANET2 hydraulic and qualitative analysis in Excel software. The objective function is formulated such that the squared difference between computed chlorine concentrations and the minimum residual concentration at all monitoring nodes at all times is minimum. The decision variables were the optimized injection dose at boosters’ locations.
The injection rate was obtained (minimum: 0, average: 183.87, maximum: 776.57 and total 4412.84 mg/min per a day) at the station as the number of generation was reduced to 200. Critical nodes formed 20% of the total nodes of network.
Based on the results, minimization of Chlorine whilst comply with FRC standard has both health and economical effects. The results can help the water distribution system management in terms of water quality (by maintaining FRC), health promotion and monetary.

Rainfall and groundwater level are important parameters of DRASTIC index, thus their time-series were examined using time series analysis for Mahidasht plain vulnerability in Kermanshah Province.
DRASTIC model is a quantitative model that seven parameters for transfer of pollution are considered including depth of water table, net recharge, aquifer, soil, topography, unsaturated environment and hydraulic conductivity. The data was prepared in seven-layer information in Arc GIS10 software. After integration, weighting and ranking, DRASTIC index for the region was estimated between 34 and 120. Precipitation is an uncertainty factor in water projects. Precipitation is the origin of other uncertainties such as surface runoff, recharge, and water balance. Underground water level and recharge are main factors in the DRASTIC model that are considered as component hydrological variables and time series, thus, they were analyzed and forecasted using stochastic methods on the horizon in 2032.
Finally, selection of the data predicted in 2032 and the creation of dual new depth to the water table and recharge, as well as the weighting and ranking of the repeated placement in the DRASTIC model, another vulnerabilities map is prepared in which the index DRASTIC was 34 to 110 units.
Results showed that due to further decrease of water table and reduced rainfall, DRASTIC index will be less in the next 18 years (2014-2032).

Mercury (Hg) contamination in marine ecosystems is a major threat to human health in the developing countries like Iran. The main route of mercury exposure is from consumption of fish and seafood. Upon entering mercury in human bodies, Hg is converted into methyl mercury, which may lead to serious implications including neurological disorders, reproductive abnormalities, kidney failure, emotional instability, gingivitis and tremors. Therefore, research on mercury concentrations in marine ecosystems (water and fishes) can be help to protect human health and reduce the risks of mercury contamination.
In this study in order to evaluate the concentrations of Hg in water and fish, water samples (36 stations), fish tissue livers (n=33) and muscles (n=33) of four fish species from the Caspian Sea (southern coasts) were collected and analyzed. For determination of Hg in water and fish samples, Voltammetry and GF-AAS techniques were used, respectively.
The results showed that the average Hg concentration detected in water samples was 1.657 (μg/L) and in fish muscle and liver tissues were 68.636 and 125.606 (μg/g.dw), respectively. The bioaccumulation factor showed that mercury concentrations from water to fish are in the range of 14 to 80 times. The highest levels of mercury in water and fish were observed in the southwest coasts of the Caspian Sea.
According to USEPA and SPPA (China) standards, more than 58 % of the water samples collected from the southern coasts of the Sea was polluted by mercury. However, the average concentrations of mercury in fish samples were less than the standards by WHO and EPA.

Nanoparticles are already widely used in technology, medicine and consumer products, but there are limited data on their effects on the aquatic environments. The aim of this study was to evaluate the response of antioxidant defense system in common carp gills exposed to silver nanoparticles, which are produced by bioreduction method.
Common carp fish were exposed to the silver nanoparticles at concentrations of 0.11, 1.13 and 5.67 mg/L for 14 days. A treatment without silver was considered as a control. After sampling, 1 g of gill was weighed and homogenized in 5 mL phosphate buffer. The homogenized samples were analyzed for measuring the activity of catalase (CAT), superoxide dismutase (SOD), glutathione (GSH), total antioxidant capacity (TAC) and malondialdehyde (MDA).
CAT activity in gill at the concentrations of 1.13 and 5.67 mg/L AgNPs was significantly reduced compared to that of the control (p0.05) was observed. Activity of SOD and MDA of all treatments sampled at different days was fluctuated, that is, it was either increased or decreased. However, superoxide dismutase activity was significantly higher in exposure to concentrations of 5.67 mg/L and 1.13 mg/L.
According to the results, fish gills are one of the most susceptible organs of oxidative damage in exposure to silver nanoparticles. This can affect the health of common carp and thus increase the risk of disease in the fish.

Extreme use of antibiotics and discharging to the environment lead to serious consequences. Mesoporous silica such as MCM-41 material is widely used to absorb contaminants from the aqueous solution. The aim of this study was to evaluate mesoporous synthesis of MCM-41 and its efficacy for removal of the antibiotic cephalexin from aqueous solution.
Physical characteristics and absorbent structure synthesized by techniques BET, FTIR and XRD were analyzed. The effect of variables such as pH values (3, 7, 11), the dose of MCM-41 (200, 500, 800 mg/L), initial concentration of cephalexin (50, 75, 100 mg/L), contact time (30, 60, 90 min), and process temperature (20, 30, 40 0C) on absorption of cephalexin were studied. In order to achieve the optimal experimental conditions, response surface methodology (RSM) model was used.
The results showed that pH (p=0.0001), adsorbent dose (p=0.0001), initial concentration of cephalexin (p=0.0001), contact time (p=0.01), pH2 (p=0.0002) and pH (p=0.04) and initial concentration had a significant impact on the response variable. The optimum removal condition based on analysis of variance and the model was at the reaction time 90 min, pH 3, initial concentration 50 mg/L and adsorption dose 600 mg/L. Under these conditions, the removal efficiency of 81.1% was achieved.
The results showed that adsorption process with the mesoporous MCM-41 had a high efficiency on the removal of cephalexin from the aqueous environments.

The failure mode and effects analysis (FMEA) is one of risk assessment techniques. The aim of this study was to identify, assess and prioritize the risk associated with the process of medical waste management using the FMEA method and provide appropriate strategies and measures for controlling the risk of this process in the Children's Medical Center Hospital.
This descriptive cross-sectional study was performed in this hospital during the first 6 months of 2016. For data collection, the standard worksheet of FMEA and object-oriented sampling were used. In this method, each error based on the severity, the occurrence rate and probability of finding an error is scored between 1 and 10, which the priority number of the risk is obtained from the product of these 3 indicators..
In this study, a total of 33 potential risks associated with the management of medical wastes were identified using FMEA risk assessments. The highest priority number for non-washed waste containers is 360 and the lowest priority number is the risk of not having the Safety box for disposal of sharp waste in the wards, which is 30.
One of the most important sources of environmental pollution is medical wastes that have high costs in different stages of waste management in the hospital, thus, the use of the FMEA technique can reduce costs and increase the safety and health of the personnel. It also helps to preserve the environment.

Attention to on-farm food safety is the first step in achieving food safety and production of healthy crops. However, practices related to on-farm food safety are not sufficiently considered by farmers due to the lack of proper understanding. Accordingly, the purpose of this study was to evaluate the attitude of farmers about sources of contamination and explaining factors of on-farm food safety practices.
This study is a non-experimental and descriptive research in terms of extent of variables control; a filed research according to data collection method; and a survey research in terms of generalizability of findings. The statistical population of the study was 732 lettuce producers in Alborz province of which a sample size of 230 was selected using a stratified sampling method with proportional allocation (counties as strata). Data was collected through research-made questionnaire. Appearance and content validity of the questionnaire was assessed by the experts in the field and its reliability was confirmed based on calculated Cronbach Alpha coefficient for three constructs including on-farm food safety practices (0.728), sources of contamination in the pre-harvest stage (0.821) and sources of contamination in the post-harvest stage (0.801). Data analysis was performed using SPSS software version 20.
The results revealed that the most important sources of contamination were the usage of pesticides and toxins on the farm and in the irrigation water (in the pre-harvest stage), locations of crop storage and warehouse and high humidity during crop transfer (in the post-harvest stage). Furthermore, the results of the factor analysis using Varimax rotation indicated that underlying the variables of on-farm food safety practices may be summarized and categorized in five factors: practices related to workers’ education and health; public health; irrigation; monitoring and control; and control of livestock and wildlife. These covered about 64.314% of total variances. Among the five factors mentioned, practices related to workers’ education and health explaining 18.1% of the total variances was the most important factor in comparison with other one.
According to the contamination sources in the pre and post-harvest stages and the probability of different contamination in lettuce crop, it is essential to provide necessary conditions for encouraging and directing producers to perform on-farm food safety practices, particularly by educating them on the identification of contamination sources and informing them about essential health and safety practices.

Background and The aim of the present study was to investigate the concentration, enrichment factor, Nemrow integrated pollution index, and potential ecological risk of heavy metals including (Pb, Ni, Cu, Zn, Cd, V and Cr) in surface soils of Ahvaz oil filed.
For this purpose, 49 soil samples with a systematic scheme from Ahvaz oil field were analyzed by atomic absorption method.
The mean concentration of heavy metals was as follow: Pb (251.20), Ni (94.6), Cu (75.80), Zn (132.84), Cd (0.69), V (4.97) and Cr (141.48) (mg/kg). The average value of enrichment factor in the soil samples decreased as Pb>Ni>Cu>Cr>Zn>Cd>V. Nemrow integrated pollution index (NIPI) indicated high level of pollution for the studied heavy metals except V. The Potential ecological risk of the studied heavy metals showed a low potential ecological risk for V, Cd, Zn and Cr; Cu showed a moderate risk and Ni and Pb indicated a considerable ecological risk. The mean value of the risk index indicated that 27 (55.10%) of the soil samples with a moderate risk, 21 (42.85%) with a considerable risk and one sample (2.05%) with a high ecological risk.
The obtained results from the enrichment factor, Potential ecological risk, and risk index indicated that the main source of heavy metals in the study area were anthropogenic sources such as oil drilling activities.

Background and Polltion of food chain components such as vegetables to heavy metals is one of the important environmental problems. Remediation management of these metals especially Cd is very important. Thus, this research was done to investigate the effect of Arak municipal waste compost enriched with tire rubber ash on decreasing spinach Cd concentration in a Cd polluted soil.
Treatments consisted of applying (0, 200 kg/ha) Arak municipal waste compost enriched with tire rubber ash and Cd pollution at the rates of 0, 10, 20 and 30 mg Cd (kg soil)-1. The plant used in this experiments was spinach.
Increasing application rate Arak municipal waste compost from 0 to 20 and 40 ton/ha in a Cd polluted soil (mg Cd (kg soil)-1) caused a significant reduction in DTPA extractable-Cd by16 and 45 %, respectively. Similar to this result, shoot Cd concentration was decreased. Applying tire rubber ash also had an important role on decreasing Cd concentration.
The results of this study showed that applying Arak municipal waste compost had an important role on decreasing Cd concentration. This was due to the application of the organic amendment on increasing soil sorption properties that it in turn decreased soil and plant Cd concentration. However, the role of plant type and soil physico-chemical properties on changes in Cd availability cannot be ignored.

In the field of environmental risk assessment, Cyanide is one of the most important pollutants of water, soil and air that has an important impact on the ecosystem and environment of the contaminated area. Therefore, the present study aimed to prove the biological effectiveness of Vetiveria zizanioides in phytoremediation of soils contaminated with cyanide.
This research study was conducted on a gold mine wastewater. The dried effluent samples amended with soil with various cyanide concentrations. Seven treatments with different concentrations of cyanide were obtained (mean cyanide content in G soil, 14.77 mg/kg, F soil, 10.13 mg/kg, E soil, mg/kg 8.09, D soil, mg/kg 7.53, C soil, 3.32 mg/kg, B soil, 2.52 mg/kg and A soil without cyanide (as control). After two months, the amount of cyanide in the soil, roots and leaves of the plant, as well as the total protein and proline content, and the number and length of the leaves of the plant were measured and then statistically evaluated by SPSS15 Tukey and t Paired Samples T Tests.
The results of this study showed that the increase of cyanide had a significant effect on the amount of proline (proline in the plant increased), total protein (in the plant increased), number of leaves (decrease in number) and the length (length reduction) of the leaves of the vetiver. The amount of cyanide in the leaves and roots of the plant was increased. Cyanide content was decreased in the different treatments. Cyanide content was decreased in G 50.93%, F 38.20%, E 27.19%, D 38.37%, C 17.77% and B 16.66%.
The results indicated that increase of the amount of cyanide in soil resulted in observational changes in the morphological and biochemical characteristics of the plant. However, Vetiveria zizanioides exhibited very high resistance to soil cyanide and the planting of vetiver in highly contaminated soils can lead to a reduction of cyanide up to 50 percent. Vetiveria zizanioides had higher resistance to cyanide and showed better phytoremediation than the other plants.

Aluminum (Al) is a neurotoxic agent and this element is being associated with Alzheimer disease. The use of semi-rigid packaging has been increased in recent years. In these packages, the main layer is aluminum. The purpose of this study was to determine the Al concentration in foods packaged in semi-rigid packaging in during storage time.
Al concentration of the samples (Joje kabab, khorake morgh, khoresh gheymeh, n=36) was determined at different storage times (0, 60, 120, and 180 days after packaging). Aluminum was determined by ICP-OES after wet digestion method of the samples. A two-way analysis of variance was used to analyze the results with respect to time and food factors.
The effect of storage time on Al concentration was significant p˂0.001. The samples that were stored longer had significantly higher aluminum concentrations. The highest concentration was determined in Joje kabab (3.27 ±0.93 ppm( and lowest Al content was determined in khoresh gheymeh (1.04 ± 0.16 ppm). The results showed that Al concentration of the foods packaged in semi-rigid packaging increased significantly during storage.
Considering the present state of knowledge and the suggested provisional tolerable daily intake of 1 mg/kg body weight per day of according to World Health Organization, Al leaching from semi-rigid packages may add low doses of Al into the diet.