mohammadhossein saghi

The emergence of new chemical industries has caused the release of a large amount of organic compounds including industrial by-products, insecticides and other chemicals in nature. Endocrine disrupting compounds are a known group of hazardous and complex pollutants that occurs in wastewater and water sources worldwide, either naturally or as a result of human activities. In this study, an attempt is made to remove diethyl phthalate from water environments by the advanced oxidation process of ozonation in the presence of activated carbon produced from the Skanbil tree.

methods and Materials:

 This experimental study was done in a reactor with a volume of 100 mL. In each experiment, diethyl phthalate solution was poured into the pilot in the desired concentration and ozone with 0.8 mg/min dose was injected into the reaction solution. Process parameters included pH (2-8), reaction times (2 to 30 min), pollutant concentration (5-25 mg/L) and catalyst dose (0.025-0.1 gram). In the end of each experiment, the sample was withdrawn from the pilot and analyzed using HPLC to determine the residual diethyl phthalate.

The results showed that under optimal conditions of pH = 6.8, ozone dose = 0.8 mg/min and contact time = 30 minutes, ozonation could only remove 60% of diethyl phthalate, and under the same conditions, catalytic ozonation with 0.075 g of carbon obtained from the skanbil tree could remove 94% of diethyl phthalate.

The results of this research showed that catalytic ozonation with carbon obtained from the wood waste of shanbil tree can be used as an advanced treatment method.

Today, heavy metals and organic compounds such as dyes are among the most dangerous pollutants that have entered surface and groundwater and threaten human health. The aim of this study was to investigate the removal of reactive orange 3R dye and chromium by adsorption separately and simultaneously activated carbon.

In this study, Sycamore carbon modified with NH4Cl was used to remove contaminants.  Effect of variables such as pH (2-9), adsorbent concentration (0.5-1-0 g/L), pollutant concentration (10-50 mg/L) and contact time (2-40 minutes) on dye and chromium removal (simultaneously and separately) were calculated. Freundlich and Langmuir adsorption isotherm models and kinetics were also investigated.

The results of this study showed that activated carbon at pH = 4, 0.4 g/L adsorbent at 15 min contact time has the best removal conditions for both paint and chromium contaminants. Under optimal conditions, activated carbon was able to remove 72% of chromium and 84% of dye separately and 59% of chromium and 67% of dye simultaneously in solution at a concentration of 25 mg/L. The study of adsorption isotherms also showed that the experiments were more consistent with the Freundlich model.The absorption kinetics follows Pseudo-second order equations.

According to the results, this adsorbent has a good performance in separate and simultaneous removal of paint and chromium and can be used to treat wastewater containing organic and inorganic contaminants.

Even in engineered landfills in developed countries, leachate production cannot be avoided and it contains different types of heavy metals. Therefore, landfills are one of the main sources of increased concentrations of heavy metals in the soil. The purpose of this study was to evaluate the severity of contamination of soils around Sabzevar landfill with heavy metals and to prepare a soil contamination map with heavy metals.

Samples of surface and deep soils were collected in 18 stations according to the type of soil and distance from landfill Sabzevar. The concentrations of heavy metals Arsenic, Zinc, Lead, Chromium, Copper, Mercury and Cadmium were analyzed by ICP-OES. The intensity of soil contamination was assessed using Index Geoaccumulation Potential ecological risk index.

The mean concentrations of Arsenic, Zinc, Lead, Chromium and Copper in surface soil, respectively are, 6.013, 41.04, 6.31, 26.77 and 31.45 mg/kg of Mercury and Cadmium, respectively, 60.79 and 61.60 μg/kg, respectively. But the mean concentration of Arsenic, Zinc, Lead, Chromium and Copper in depth soil, respectively are, 5.75, 38.33, 6.25, 22.68 and 31.04 mg/kg, Mercury and Cadmium, respectively, 66.57 and 59.98 μg/kg, the value of all proportion to Natural background values are higher.

Based on estimates of Igeo and RI indices for heavy metals Arsenic, Lead, Zinc, Chromium and Copper in the soil showed no contamination but for Mercury and Cadmium showed severe contamination.

Penicillin G (PG) is one of the most widely antibiotics used around the world. The release of PG in an aqueous solution leads to contamination of water resources. This study aimed to determine the efficiency of modified Eskanbil activated carbon for the removal of PG from aqueous solutions. The NH4Cl-induced activated carbon was synthesized by a simple method and used for the degradation of PG in contaminated water.

Activated carbon was characterized by Fourier transform infrared spectroscopy (FTIR), Field emission scanning electron microscopy (FESEM), and Brunauer–Emmett–Teller (BET) surface area analysis. The influence of important parameters including solution pH, contact time, and initial PG concentration, and dosage of adsorbent was examined on the efficiency of EAC in degradation of penicillin G in aqueous solution.

The synthesized carbon was characterized. The BET results indicated that the surface area of the Activated Carbon catalyst was1473 m2/g. The maximum PG adsorption onto EAC was observed at the pH of 6. The PG removal of 33% at an EAC concentration of 0.1 g/L increased to 99.98% at an activated carbon concentration of 0.5 g/L. The isotherm and kinetic studies of PG removal by EAC showed that the Freundlich model (R2>0.995) and the pseudo-second-order (R2>0.983) equation represented the best fit with the adsorption data.

EAC is recommended as a suitable and cost-efficient adsorbent for removing poisons, pharmaceuticals, and other emerging contaminants from water resources.

Using the effective approaches for modifying the recycled wood as a novel bulky agent improves the quality of soil amendment. This study aimed to compare the stability and maturity of the soil amendments produced by the compostation of forest industrial waste and sewage sludge on seed germination.

Three materials, namely sawdust, sewage sludge, and chicken manure were mixed at different ratios (dry weight basis) to reach the initial bulk density of 0.40 Kg.L-1, the temperature of 30 °C, the C/N ratio of 25, and the moisture content of 60 %. A pilot-scale composting process was applied to monitor the aeration rate, temperature, and moisture contents during the process over time. The comparison of physico-chemical, phytotoxicity, and germination indices among the samples was performed in three repetitions.

The results of this study indicated that the sustainable conditions (i.e., the temperature of 70 °C, aeration rate of 0.30 L.Kg-1DM.min-1, and moisture content of 50-60 %) can have a significant effect on the thermophilic stage for compost curing without any inhibitory repercussion. Increasing the germination index of cress (Lepidium sativum) up to 79 % proved that the toxicity of industrial sewage sludge was declined through the elimination of heavy metals.

This study revealed that the availability of bulky agents such as wood residue can reinforce the microbial activity by continuously decreasing the C/N ratio to the minimum value of 13.2.

In recent years, the uses of chemical pesticides in agricultural crops more than the world standards. The aim of this study was evaluate the knowledge, attitude and practice of farmers in Jovuin on the environmental health aspects of pesticide use in the 2018 years.

This is a cross-sectional study. The population of this study is farmers of Jouvin of Khorasan Razavi province. The sample size for study was 100 farmers. The data obtained with a standard questionnaire and data analysis was performed using SPSS version 20 software.

The knowledge, attitude and practice of farmers in relation to environmental health and safety principles during spraying indicate that the average score was 12.43 in attitude and awareness, but the very low mean score of individuals (5.46) in the performance. Also Pearson analysis showed the have scientific relation with attitude and awareness. (P-Value>0.05)

The practice of farmers in this study has received a very low score. This subject requires the scientific and practical training of farmers so that they can be used to reduce the amount of toxins consumed and thus reduce the pollution of the environment

Endocrine Disrupting Chemicals (EDCs), and potential EDCs are mostly man-made, found in various materials such as pesticides, metals, additives or contaminants in food, and personal care products. Phthalates are a group of these compounds that are carcinogenic to animals and can cause fetal death and congenital anomalies. The aim of this study was to investigate the photocatalytic process using GO/ZnO nanocomposites under LED irradiation for removal of Endocrine Disrupting Chemicals (EDCs) from aqueous solutions.

In this study, GO/ZnO nanorods were characterized by, Field emission scanning electron microscopy, transmission electron microscope, and Brunauer–Emmett–Teller surface area analysis. A Central Composite Design was used to optimize the reaction parameters for the removal of DEP by GO/ZnO. The four main reaction parameters optimized in this study were the following: the LED radiation time, pH, and the initial concentration of phthalates and the concentration of ZnO and graphene-oxide. The interaction between the four parameters was studied and modeled using the Design Expert 10 software. Phthalate detected by HPLC apparatus equipped with a UV detector at 225 nm wavelength with methanol (90%) and Acetonitrile (10%) phases.

The results of FE-SEM and TEM showed that the ZnO is composed of a bar and separate face. Based on the peak obtained, the diameter and length of the nanorods are 20-60 and 200 nm respectively. A maximum reduction of 90% of DEP was achieved at pH 5 and 120 minutes. The results represent the prediction of a model fitted from the Quadratic model (p-value<00001).

The interaction of variables showed that the maximum effect was belonged to the pH and the time in the process reactions. Also, the results showed that the GO/ZnO low power LED irradiation can be used as an effective method for the removal of EDCs from environmental.

One of the most important environmental pollutants that there is in sewage of different industrials is cyanide to cause pollution of water sources that are dangerous to humans and the environment. Cyanide can be removed in different ways from the aqueous media, but most of these methods are costly. Therefore, the aim of this study is the removal cyanide using iron nanoparticles.

Removal of cyanide from aqueous media using iron nanoparticles in various conditions including the effect of the adsorbent, initial cyanide concentration, contact time and pH were studied in discontinuous phase. In this study, adsorption equilibrium and also the kinetics of the reaction examined.

In the process of sharing discontinuous, the balance was achieved after 120 minutes of contact time and maximum amount of removal cyanide in the pH =11 for cyanide concentration of 2.5 mg/L and 1 gr of nanoparticle over 97% obtained. Also the results showed that the adsorption process fitted with Langmuir isotherm and chemical kinetic fitted with of secondary grade.

According to the findings, iron nanoparticles can be used as a suitable option for removal cyanide from aqueous solution in hazardous waste. Keywords: iron nanoparticles, cyanide, hazardous waste

Gamma ray radiation can cause ionization and harmful effects on human health due to its high levels of energy. However, contrary to popular belief, natural sources of gamma radiation are far greater in number than artificial sources. This study aims to determine the environmental gamma dose rate and the zoning map of Tehran, and estimate the annual effective dose and the excess risk of cancer in Tehran.
This study is descriptive and cross-sectional. In it, the researchers measured the gamma radiation rate using a Geiger Muller detector at 50 outdoor stations in Tehran during the winter and the spring of 2016. The data was zoned using Arc GIS 10.3.
The average background environmental gamma dose rate in Tehran was obtained at 605.54 nsv/h. There is a statistically significant difference between radiation in winter and in spring (P The annual effective dose and cancer risk in the lifetime of a Tehran city resident due to background gamma radiation were higher than the global average. Epidemiologic studies are recommended to assess the likely prevalence of chronic diseases associated with natural radiation among the residents of Tehran.

In Iran, for people who have health insurance, an insurance package for basic dental services is also available. Nevertheless, unmet dental needs have been reported in the country. The aim of this study was to determine the extent of use of insurance package for basic dental services among attenders of health centers of Mashhad in 2011. In this cross-sectional study with cluster sampling, a total of 1200 attenders to health centers of Mashhad were interviewed and variables such as age, level of education, the name of health insurance, and insured dental services that was received in the year prior to study were evaluated using SPSS software with chi-square and Mann-Whitney statistical tests. Of 1200 people studied, 1094 subjects (91%) had health insurance coverage. 258 subjects (23.5%) had used basic dental insurance services in the past year. Women received significantly more services than men (P = 0.03). Type of services received were different depending on level of education (P = 0.001), as in people with less education or illiterate, tooth extraction and dental prostheses were more common. Subjects with 51 ​​years of age and older had less commonly used insurance package for basic dental services compared to other age-groups (P = 0.04). The frequency of dental services received by individuals covered by social security organization insurance, was higher than other insurance agencies (P < 0.001). Despite the appropriate insurance coverage, the use of insurance package for basic dental services was low. Hence, it is necessary to be examined why usage of insurance package for basic dental services is not welcomed by Iranian people.

Due to the high production rate and the manual nature of the manufacturing of Arc opal dishes the probability of the musculoskeletal disorder onset is high. The aim of present study was to detect and assess the risk of musculoskeletal disorders and its relation to the work pace among the staffs in one of the dishes manufacturing companies. This cross-sectional descriptive-analytical study was carried out on the 100 staffs employed on the decoration section of the company that had job experience equal to one year. They was selected randomly.. To detect the disorders in different parts of the body and to assess the risk of MSDs were used Nordic questionnaireand QEC method respectively. Using SPSS15 software، we analyzed data that used one way ANOVA and Independent Sample t- test. The results from Nordic questionnaire revealed that the most prevalent disorders in past year related to back (93%)، neck (89%)، and shoulder (82%) regions respectively. The QEC showed that level of worker exposure with risk factors in back (53%)، shoulder (58%)، Wrist – Hand (71%) and neck (58%) regions is high. Also 71 percent of worker employees have inappropriate posture during work. A significant relation was found between the MSDs and the work pace. Considering the high prevalence of MSD and analyzing the related risk factors which signifying the risky condition of work environment، it proposed to apply the ergonomic intervention for reduction of work pace.

Unnecessary use of chemical manure in order to increase the crop production، particularly in the agricultural sector، causes environmental damages and disorder in terms of soil fertility. In the manure preparation method through the biogas، organic manure of high quality can be produced in addition to obtaining gas. The purpose of this study is to examine the physical as well as chemical properties of the manure produced by the combined wastes of livestock and poultry using biogas system. Research

In order to put the pilot project into operation، livestock and poultry wastes were primarily collected and were added to the planned pilot in a proportional ratio of 1:2. After about two months، the produced gas was measured and the parameters of the manure were analyzed according to the pilot sample and subsequently، they were compared with the existing standards. Using EXCEL، the gathered data were analyzed.

PH rate obtained from the manure was estimated to be 7. 2. Reportedly، the electrical conductivity of the sample was equal to 29. 53 ml. Siemens/cm. and the humidity was 5%. The organic compounds in the sample were 8. 19% and ash was 8. 58%. Furthermore، the rate of the organic carbon for the sample was 40% and the size of the uniformed particles was of the highest mesh، i. e. 50. The manure obtained has a phosphorous concentration of 1 mg/l and the sodium concentration obtained were 94 mg/l and potassium 74 mg/l. Discussion and

Findings indicate that the rate of organic materials، phosphorus، ash and organic carbon are consistent with the standards set by WHO. With regard to low cost، availability، being danger-free and enriched as well as the simultaneous use of the gas produced، the manure obtained through the biogas can be considered a suitable kind of manure for agriculture.