Showing 59 results for Mohammadi
M Mohammadian, J Nouri, N Afshari, J Nassiri, M Nourani,
Volume 1, Issue 1 (26 2008)
Abstract
Background and Objectives: Heavy metals processing industry has always been a major cause of concern which affects soils, surface waters, ground waters and river sediments contaminations. Thus, the Zanjan Zinc and Lead Smelting Plant has been considered as a potential source of contamination.
Mterials and Methods: This cross-sectional study has been conducted in February 2008 in the site region .The concentrations of Lead, Zinc and Cadmium have been assessed. The samples have been taken from 17 wells and atomic absorption spectrophotometeric method has been used to assess the samples. In order to find out and locate the exact situation of the wells under study, Global Positioning System instrument has been used. The correlation between the concentration of each metal and the distance of studied well from the plant has been assessed too.
Results: The findings of this study showed that lead and cadmium concentrations were 53% and 59% respectively out of the guideline values of World Health Organization.
Conclusion: The concentration of Zinc was lower than both national and international values in all samples. As the heavy metal concentration is very important for human health status, the other fields of study like heavy metal air pollution effects and related diseases and conditions should be studied and assessed.
Ar Mesdaghinia, F Vaezi, E Dehghanifard, Ah Mahvi, M Alimohammadi,
Volume 1, Issue 1 (26 2008)
Abstract
Background and Objectives: Measurement of light intensity is a recommended practice for insuring the delivery of required germicidal dose in disinfection operations by UV lamps. Use of sensitive to light chemicals which is the base of actionometeric methods could be considered as a suitable manner for estimating the intensity of UV lamp in circumstances that special radiometers are not available.
Materials and Methods: lodide-iodate mixture was used as an actinometer for this study. The light intensities of a UV lamp (LP 25W) were first determined by a special UVC radiometer at certain distances from the lamp. Then the test of determining the suitable period of time for irradiation of actinometer was accomplished. Finally، the color changes of iodide - iodate solutions at the predetermined distances were evaluated at the wavelength of 352 nm. The latter analysis can be done by a common (visible) spectrophotometer.
Results: Results indicated that use of this actinometer is more suitable at the distances of 35 to 60 cm from the center of the lamp bulb، since iodode-iodate solution has a detectable color change at this range of distance in one minute irradiation which may be considered as a reasonable time for actionmeteric operations.
Conclusion: Although all kinds of actinometers should not be regarded as precise as special radiometers and there would be need to use pure chemicals for actinometeric determination of light intensity، it can be claimed that the recommended procedure in this study which is the newest actinometeric method can be used in acceptable evaluation of UV intensity with least difficulty in providing necessary instruments.
A.r Yazdanbakhsh, A Sheikh Mohammadi, M Sardar, H Mohammadi, M Zarabi,
Volume 2, Issue 4 (9 2010)
Abstract
Backgrounds and Objectives: A great part of organic compounds cause more pollution in natural waters meet, are chemical dye material. Azo dyes have more usage in different industries. Azo dyes not only give undesirable dye to the water but also have mutation potential and carcinogenesis effects in human and cause the production of toxic substances in water environments.The purpose of this study is investigation of iron powder, hydrogen peroxide and iron powder-hydrogen peroxide processes in removal of acid yellow 36 dye from aqueous solutions.
Materials and Methods: This study was conducted in laboratory scale. At this experiment synthetic solution was made from acid yellow 36 dye, and the removal of acid yellow 36 dye was studied by iron powder, hydrogen peroxide and iron powder- hydrogen peroxide processes .Also effect of dye concentration, pH solution, hydrogen peroxide concentration, iron powder concentration and the time of contact on decolorization, were evaluated.
Results: The results showed that iron powder - hydrogen peroxide process, compared to two other process has high decolorization power. Removal efficacy of iron powder-hydrogen peroxide process with H2O2 =23.33 ml / L, pH =3, iron powder 2000 mg/L and 60 minute ,was about 97.9%
Conclusion:In general this investigation showed that , this method (Iron powder-hydrogen peroxide process) has high efficiency for removal of Azo dyes. But application this method in the industry, should be economically evaluated.
M.t Samadi, M.h Saghi, K. Ghadiri, M. Hadi, M. Beikmohammadi,
Volume 3, Issue 1 (3 2010)
Abstract
Backgrounds and Objectives:Phosphate discharges from domestic and industrial waste water to water bodies. High concentrations of phosphate in water stimulate the eutrophication phenomenon that causes taste and odor in water, losing dissolved oxygen and aquatic life in rivers or surface waters. Aim of this study is survey of phosphate adsorption on simple nano zeolite Y and nano zeolite Y that was modified with a cationic surfactant (HDTMA-Br).
Materials and Methods:In This study we used simple nano zeolite Y and nano zeolite Y in form of Surfactant Modified Zeolites (SMZs) using batch tests to adsorption of Phosphate fromAqueous Solutions. The adsorbants were contacted with different initial phosphor concentrations (5, 10 and 15 mg/l), pH (4, 7, 12), contact time (30, 60, 90, 120, 150 and 180 minutes) and weight of adsorbant (0.2, 0.4, 0.6, 0.8 and 1g). the extracted solution was determined for Phosphate concentration by the ammonium molybdate and tin chloride method with spectrophotometric detection at 680 nm. Results:Results of this study show that, with increase in contact time, decrease in pH, increase in zeolites concentration and decrease in initial phosphate concentration, the removal efficiency increased. And the Both isotherm of Langmuir and Freundlich models (r2 > 0.997 and r2 > 0.996 respectively) were agreement with adsorption equilibrium of phosphate. Reduced Chi-Sqr For Langmuir and Freundlich models were (0.00079) and (0.0011) respectively. Pseudo first-order kinetic models fits well with experimental data (r2>0.963).
Conclusion: From this survey, it is concluded that performance of modified nano zeolite Y for adsorption of phosphate in same conditions is better than non-modified zeolite Y. In general the modified nano zeolite Y presented a good profile for removal of phosphate. Therefore SMZs is a suitable candidate for removal of Phosphate molecules from contaminated solutions in contaminated waters.
M Manshouri, A Yazdanbakhsh, M Sardar, A Sheykh Mohammadi,
Volume 3, Issue 4 (8 2011)
Abstract
Backgrounds and Objectives: Reactive dyestuff has potential of toxicity, carcinogenesis and mutagenesis for mammals and aquatic organisms. The current physical and chemical methods such as adsorption, coagulation, precipitation, filtration and ... can been used for removing of dyestuff. Biological treatment which is effective and economic for decontamination of dyestuff wastewaters was preferred because of limitation and difficulty of physicochemical methods. In order to investigate the trend of pollution reduction of color compounds, ability of Remazol Black-B dyestuff removal from aqueous medium by bacterial consortium under anoxic conditions was studied.
Materials and Methods: The mix culture of bacteria from textile industries activated sludge was enriched in luria broth medium containing RB-B dyestuff as a carbon source. Then biodegradation was assessed in 4 batch reactors. Microbial population of bacterial and decolorization quantities of samples were detected by MPN and UV-Vis spectrophotometer.
Results: Decolorization efficiency by the bacterial consortium was obtained more than 99% for 50 and 250 mg/L concentrations in 72 and 144 h (3 and 6 days) respectively, while for the initial concentration of 500 mg/L was 98.1in 240 h (10 days) of biodegradation period. Dyestuff reduction rate after completed removal was about 0.69, 1.74,2 mg/L/h for initial concentration of 50, 250, 500 mg/L respectively.
Conclusion: Results showed that Alcaligenes denitrificans and Alcaligenes xylosoxidans bacteria
which were isolated from activated sludge have good potential of RB-B dyestuff removal and this removal is depending on primary concentration of dye. Removal efficiency increased as primary concentration went up.
K Naddafi, M.r Zare, M Younesian, M Alimohammadi, N Rastkari, N Mousavi,
Volume 4, Issue 2 (9 2011)
Abstract
Background and Objectives: This study was conducted to investigate the toxicity of Titanium Oxide (TiO2) and Zinc Oxide (ZnO) nanoparticles as two of most widely used nanoparticles. The result of this study can help to designing environmental standard and legislations for nanoparticles.
Materials and Methods: Different concentrations of nano ZnO and TiO2 nanoparticles were added to nutrient Agar culture media. Then, definite numbers of Escherichia coli and Staphylococcus aureus bacteria were added to culture media and inhibition of these bacteria growth was measured in comparison to controls. Obtained data were analyzed to determine nanoparticles' EC50 and NOEC (No Observed Effect Concentration) using SPSS ver.16 and Probit standard test.
Results: 24-hours EC50 of nano ZnO using E. coli and S. aureus determined to be 5.47 mg/L and 2.38 mg/L respectively. In addition, 24-hours EC50 of nano TiO2 using E. coli and S. aureus determined to be 5366 mg/L and 3471 mg/L respectively. In the case of ZnO nanoparticles, no observed effect concentration determined to be 1.15 and 3.28 mg/L for E. coli and S. aureus respectively and in the case of TiO2 nanoparticles no observed effect level determined to be 1937 and 1184 mg/L for E. coli and S. aureus respectively.
Conclusion: This study showed that acute toxicity of nano ZnO is by far more than that of nano TiO2. Regarding the EPA acute toxicity criteria, nano ZnO is categorized as moderately toxic and nano TiO2 is categorized as practically non toxic. Hence, regarding the acute toxicity, in recommending exposure criteria and environmental disposal standards, compared to nano TiO2, nano ZnO requires more attention.
R Khosravi, G.r Moussavi, Sh. Roudbar Mohammadi,
Volume 4, Issue 4 (2 2012)
Abstract
Background and Objectives: Effluent generated in several industries contains phenolic compounds, which have been classified as priority pollutants. Due to its toxicity, the conventional systems are inefficient for treatment of phenol-Laden wastewater. Biological processes using pure microbial culture, including fungi and yeast, are environmentally friendly techniques capable of complete destruction of contaminants.
Materials and Methods: This work was aimed at investigating the efficiency of a fungi specie in the decomposition of high concentrations of phenol ranging from 500 to 20000 mg/L. Several batch reactors were operated at different phenol concentration. The concentration of residual phenol was monitored over time using colorimetric method 4-aminoantipyrine. The removal efficiency was calculated considering the initial phenol concentration.
Results: Experimental data indicated that the phenol could efficiently degrade using the selected culture. The developed granules could completely degrade phenol at concentrations up to 20000 mg/L.
Conclusion: It can be concluded from the experimental data that the biodegradation using the Fungi granules is a very efficient and thus promising technique for treatment of wastewaters containing phenolic compounds.
Ramin Nabizadeh Nodehi, Hassan Aslani, Mahmood Alomohammadi, Reza Nemati, Kazem Naddafi, Maryam Ghany,
Volume 5, Issue 2 (13 2012)
Abstract
MicrosoftInternetExplorer4
Background and Objectives: Irrigation of agricultural crops using wastewater will
increase, in some cases, their growth by 40 to 60 percent. However, this has a
high risks for human health because of the presence of higher number of
pathogenic organisms. The main purpose of this study was to investigate the
feasibility use of Fenton and modified Fenton with copper for the disinfection
of raw wastewater.
Materials and Methods: After primarily laboratory physicochemical and biological analysis, the
disinfection process was performed in three different phases in each process.
First, the disinfectants were injected separately, then we performed
disinfection using Fe++ and cu++ ions combined with hydrogen peroxide in order
to determine synergistic effect of each catalyst. Direct method was used for
fecal coliforms counting.
Results: Hydrogen
peroxide maximum efficiency for inactivation of fecal coliforms was only
0.66log inactivation. Fenton and modified Fenton with copper ions showed a
remarkable effect on the bacterial inactivation so that Fenton and modified
Fenton with 1 and 2 mg/l of Cu++ inactivated coliforms by 4.73, 3.28, and 4.88
log respectively.
Conclusion: Application of HP alone for the disinfection of raw wastewater is not
practicable due to low observed efficiency. However, its combination with ions
such as Fe++ and Cu++ increases HP performance in disinfection and has a
notable synergistic effect on HP
disinfection power, where, in the presence of each catalyst, hydrogen
peroxide can reduce the fecal coliforms of raw wastewater to meet the Iranian
Environmental Protection Agency Standards.
Kazem Naddafi, Mehran Mohammadian Fazli, Ali Reza Mesdaghinia, Simin Nasseri, Mahnaz Mazaheri Assadi, Masoud Yunesian,
Volume 5, Issue 2 (13 2012)
Abstract
MicrosoftInternetExplorer4
Background and Objectives: Environmental pollution and health risks of dyestuffs
extensively are caused by many industries. Nonbiodegradability of dyes is
important so that different methods are studied for removing them. The use of
white rot fungi is promising technique in this regard. Therefore, objective of
this work is to investigate Rimazol Brilliant Blue Royal decolorization by
immobilized Ganoderma sp. in sodium alginate from aqueous solution.
Material and Methods: This is an experimental study. First, the nutritional, environmental, and
operational conditions of decolorization process were optimized. Then,
efficiency of immobilized fungal cells was investigated. Experimental designs
were provided using fractional factorial methods and quadratic model was fitted
on decolorization data by MiniTab software.
Results: Our findings
showed that type and concentration of carbon source, temperature, and pH were
the most important factors affecting decolorization and statistically
significant. Optimal conditions to 95.3 percent color removal were: glycerol as
carbon source at 19.14 g/L temperature, 27 oC and initial pH, 6.26. Moreover,
decolorization efficiency increased from 75 percent up to 95 percent by improving
process and fungal immobilization.
Conclusion: Ganoderma
fungus has suitable potential to decolorization. Besides, optimization and cell
immobilization can improve its capability. Application of experimental design
to research methodology is important because of decreasing in experiments and
saving resources. It is suggested to use these potentials in environmental
pollution control.
Mohammad Reza Massoudinejad, Akbar Eslami, Hamed Mohammadi, Hossein Najafi, Behzad Rezayi Fard, Gholam Hossein Joshani,
Volume 5, Issue 2 (13 2012)
Abstract
MicrosoftInternetExplorer4
Background and Objectives: The
increasing demand for drinking water has led scientists to the use of saline waters,
but existing desalinating processes are very expensive. carbon aerogel is a
type of organic aerogel that is suitable for desalination owing to its
unique porous structure. Low
potential of fouling and deposits, very low wastewater
production, electrostatic regeneration of aerogels and, in turn, no need
to acid consumption, and lower power consumption are some of this
technology benefits.
Materials and Method: In
this experimental- analytical study, the purpose was survey of saline
and brackish water desalination using carbon aerogel technology and
its comparison with electrolysis.The
community
studied was synthetic salt
water
samples, using of TDS and
EC indicators. The minimum synthetic samples were 243. In this regard, after polymerization of
Resorsinol and Formaldehyde compounds under ambient pressure conditions
and then its pyrolysis, we fabricated plates of carbon aerogel.
Result: With
manufacturing in the pilot-scale, the effect of different parameters, including
input salt concentration, current, water flow, distance of
between electrodes and pH, on NaCl sorption amount of carbon aerogel
electrodes were studied. Generally,
adsorption amount increased with increasing of current and NaCl
concentration and decreased with increasing of distance electrodes, flow and
pH.
Results: Fabricating
reactor at
pilot-scale, we studied the effect of different parameters, including
input salt concentration, current, water flow, intra-distance
of electrodes, and pH on the NaCl sorption using carbon aerogel electrodes. Generally, adsorption capacity increased
with increasing of current and NaCl concentration in the inlet flow,
and it decreased with increasing intra-distance of electrodes, flow, and pH.
Conclusion: Under the most optimal conditions, our results showed that the NaCl
adsorption rate on carbon aerogel electrodes was about 1.43×10
-4 M
NaCl per g of carbon aerogels indicating its cost-effectiveness.
Mohammad Reza Mehrasbi, Sorur Safa, Amir Hossein Mahvi, Ali Assadi, Hamed Mohammadi,
Volume 5, Issue 3 (21 2012)
Abstract
Backgrounds and Objectives: The base structure of total petroleum hydrocarbons (TPH)
is made of hydrogen and carbon. Widespread use, improper disposal and
accidental spills of this compounds lead to long term remaining of
contaminations such as organic solvents and poly aromatic hydrocarbons (PAHs)
in the soil and groundwater resources, resulting in critical environmental
issues. In this study, an oil-contaminated soil was washed using Tween 80
surfactant and the application of photo-Fenton process (UV/Fe2+/H2O2)
for treatment of the produced wastewater was evaluated.
Materials and Methods: Tween 80 is a yellow liquid with high viscosity and soluble in water. In order
to determine of the photo-Fenton process efficiency, we studied effective
variables including Fe concentration, pH, H2O2 concentration, and irradiation time. The UV irradiation source was a
medium-pressure mercury vapor lamp (400 w) vertically immersed in the solution
within 2L volume glass cylindrical reactor.
Results: The results
showed that efficiency of COD removal depends on the initial Fe concentration, pH,
H2O2 concentration and irradiation time.
Under optimum conditions, (Fe: 0.1mM, H2O2:
0.43 mM, pH: 3 and UV light irradiation time: 2 hours) the removal efficiency
of COD was 67.3%. pH plays a crucial role in the photo-Fenton process such that
the removal efficiency increased with decreasing of pH.
Conclusion: According
to the results of this study, under acidic condition, this process is an
efficient method for COD removal from the wastewater studied.
Abdolmotaleb Seid-Mohammadi, Hossein Movahedian Attar, Mahnaz Nikaeen,
Volume 5, Issue 4 (15 2013)
Abstract
MicrosoftInternetExplorer4
Background and Objectives: Contamination of drinking water sources with nitrate may
cause adverse effects on human health. Due to operational and maintenance
problems of physicochemical nitrate removal processes, using biological
denitrification processes have been performed. The aim of this study is to
evaluate nitrate removal efficiency from drinking water using autotrophic
denitrifying bacteria immobilized on sulfur impregnated activated carbon in a
fluidized bed bioreactor.
Materials and Methods: After impregnating activated carbon by sulfur as a microorganism carriers and
enrichment and inoculation of denitrifying bacteria, a laboratory-scale
fluidized bed bioreactor was operated. Nitrate removal efficiency, nitrite,
turbidity, hardness and TOC in the effluent were examined during the whole experiment
under various conditions including constant influent nitrate concentration as
90 mg NO3--N/l corresponding to different HRT ranging from 5.53 to 1.5 hr.
Results: We found
that the denitrification rates was
depended on the hydraulic retention time and the nitrate removal efficiency was
up to 98% and nitrite concentration was
lower than 1mg/l at optimum HRT=2.4 hr respectively. Moreover, there was no
difference in hardness between influent and effluent due to supplying sodium
bicarbonate as carbon source for denitrifying bacteria. However pH, TOC, hardness, and turbidity of
the effluent met the W.H.O guidelines for drinking water.
Conclusion: This
study demonstrated that an innovative carrier
as sulfur impregnated activated carbon could be
used as both the biofilm
carrier and energy source for
treating nitrate contaminated drinking water in the
lab-scale fluidized bed bioreactor.
Amir Sheikh Mohammadi, Mahdieh Sardar,
Volume 5, Issue 4 (15 2013)
Abstract
MicrosoftInternetExplorer4
Background
and Objectives: Antibiotics are
potential pollutants that represent an important environmental problem because
of their toxic effects on the food chain and aqueous streams. The objective of
this research was to study the adsorption of penicillin G on to chestnut shell
as an inexpensive adsorbent.
Materials and Methods: This study was performed at laboratory scale
and batch system. We studied the influence of process variables such as
adsorbent dose, initial PEN G concentration, pH of solution, contact time, and
breakthrough curves. In order to find out the possibility of reuse, desorption
study was also carried out. The surface characteristics of adsorbent were
investigated using Fourier Transform Infra-Red and Scanning electron
microscope. Equilibrium study data were modeled using Langmuir, Freundlich, and
D-R models. Moreover, kinetic studies
were done by three models of pseudo first order, pseudo second order, and
intra-particle diffusion.
Resuls: The maximum
PEN G removal achieved was 92%, at pH 3, adsorbent dose 0.1 g/l and contact
time 120 min. The Langmuir equation (R
2=0.99) provided the best fit
for the experimental data. It was also found that adsorption of PEN G by
chestnut shell followed pseudo- second order model (R
2= 0.992).
Conclusion: According to the results obtained, chestnut
shell appears to be a suitable, low cost and efficient adsorbent for removing
PEN G from waste streams.
Mahran Mohammadian Fazli , Jalil Nassiri , Ramin Nabizadeh, Mohammad Reza Mehrasbi,
Volume 6, Issue 1 (5-2013)
Abstract
Backgrounds and Objectives: Medical waste management is one of the important issues in solid waste managment in each community. This research was carried out to study the quantity, quality and the management practices of solid wastes of hospitals in Zanjan City in 2011.
Materials and Methods: In the present study, the hospital wastes were categoried and weighted into four main categories. Waste management pattern was studied based on a checklist extracted from national guidelines. Then, hospitals were ranked from very poor to excellent classes. For data analysis, Excel soft ware was used.
Results: Waste generation rate was on average 2.402± 0.163 Kg/bed.day in the studied hospitals. The generation rate of domestic waste, infectious waste, sharp wastes, and chemical - pharmacological waste was 1.432±0.059, 0.926±0.096, 0.029±0.0055, and 0.015±0.002 kg/day.bed respectively. The status of the waste management practices was determined as average.
Conclusion: Waste generation rate in the hospitals of Zanjan was lower compared with the expected average value in other cities (e.g. 2.71 Kg/bed.day in Tehran). The percentage of medical waste in Zanjan hospitals was 34, which is higher than W.H.O. recommendations. Therefore, it is strongly recommended to reform and monitor certain solid waste management practices in order to reduce health and environmental issues.
Gholamreza Goudarzi, Mohamadjavad Mohammadi, Kambiz Ahmadi Angali, Basir Mohammadi, Zahra Soleimani, Aliakbar Babaei, Abdolkazem Neisi, Sahar Geravandi,
Volume 6, Issue 1 (5-2013)
Abstract
Background and Objectives: According to the WHO estimates, air pollution is accounted for about 800000 premature death of cardiovascular and respiratory disease and lung cancer resulted from air pollution throughout the world approximately 150000 cases of those deaths occur in south Asia. The studies conducting on short-term and long-term effects are reported in terms of admission rate, consulting with a physician, number of a particular disease, death, and years of the lost life (YOLL). We used Air Q2.2.3 (Air Quality Health Impact Assessment) Model to evaluate adverse health effects caused by NO2 exposure in Ahvaz City during 2009. NO2 reacts with ammonia, moisture, and other compounds to form small particles. These small particles penetrate deeply into sensitive parts of the lungs and can cause or worsen respiratory disease, such as emphysema and bronchitis, and can aggravate existing heart disease, leading to increased hospital admissions and premature death.
Materials and Methods: First the data required was collected from Ahvaz Environment Organization and Meteorological Organization. Then, this data were processed by Excel software through correcting temperature and pressure, coding, averaging and filtering. Finally, the data processed were entered to Air Q model. This model is a valid and reliable WHO-proved tool to estimate the potential short term effects of air pollution. This model includes four screen inputs (Supplier, AQ data, Location, Parameter) and two output screens (Table and Graph).
Results: It was found that the Meteorological and Environment Organization stations have had the maximum and minimum NO2 concentration respectively. Moreover, the annual, summer, and winter average and 98cile of this pollutant was 27, 6, 43, and 115 µg/m3 respectively. The cumulative number of myocardial infarction resulted from NO2 exposure was estimated to be nine persons per year. This value for the cardiovascular death was found to be 19 cases. Finally, the COPD cases was estimated to be seven per year.
Conclusion: Air Q software calculated relative risks, attributable proportion, and baseline incidence using data processed by Excel and presents the output as the cause specific deaths. It is noteworthy that there is no model that can estimate all of the pollutants health effects simultaneously. Cumulative number of persons for acute MI attributed to NO2 exposure was 9 in 2009. Moreover, 51% of this number occurred in the days with concentrations lower than 60 µg/m3. It should be noted that 72% of this value are corresponded to the days with concentrations below 90 µg/m3. The total cumulative number of cardiovascular death attributed to exposure with NO2 during one year of monitoring was 19 persons. 60% of these cases have occurred in days with NO2 levels not exceeding 90 µg/m3. Cumulative number of hospital admission of COPD attributed to exposure with NO2 during one year of monitoring was 7 persons.87 % of these cases have occurred in days with NO2 levels not exceeding 110 µg/m3.
Mohammad Reza Mehrasebi, Mansour Baziar, Kazem Naddafi, Mehran Mohammadianfazli, Ali Assadi,
Volume 6, Issue 2 (9-2013)
Abstract
Background and Objectives: Soil pollution by oil compounds is a serious environmental and ground water problem throughout the world. Total petroleum hydrocarbons (TPH) are a combination of many distinctive compounds. Some of these compounds in exposure with human and animal can cause cancer, disorder central nervous system, liver and lungs affects. The objective of this research was to investigate gasoline removal (C10 – C 28) using Brij 35 and Tween 80 from polluted soil. Materials and Methods: In this experimental study, the efficiency of soil washing with nonionic surfactants (Brij 35, Tween 80) for remediation of gasoline polluted soils was studied. The effects of soil washing time, agitation, surfactant concentration, and pH on the removal efficiency were studied. Results: The results showed that gasoline removal efficiency increased with increasing agitation speed and washing time. In addition, it was found that removal efficiency of gasoline was decreased by increasing surfactant concentration. But, increasing pH did not have remarkable effect on removal efficiency of gasoline. The efficiencies of Tween 80 and Brij 35 for removal of gasoline under optimal condition were 70 -80 and 60- 65% respectively. Conclusion: The results showed that soil washing with non ionic surfactants was effective in removal of gasoline from polluted soil and it can be recommended for treating surface soil polluted.
Farin Fatemi, Hamed Mohammadi, Ali Ardalan, Kazem Naddafi,
Volume 6, Issue 2 (9-2013)
Abstract
Background and Objectives: On August 2012, two earthquakes measured 6 and 6.2 on the Richter scale took place in Eastern Azerbaijan province. Environmental Health Department is accounted as one of the main units for providing and supervising environmental sanitation services at the emergencies, therefore, the objective of this study was allocated to assess environmental health response performance in recent earthquake.
Material and Methods: Through multi-stages stratified sampling, we selected 8 and 4 villages from the earthquake zones of Heris and Varzaghan respectively. The collecting data tools in this research were the WHO checklist in 7 categories, 14 subcategories, and 37 environmental health activities and also the minimum standards of Sphere Project checklist. The status of environmental health in each village was assessed using the mentioned checklists. This study was carried out with attendance of research team in earthquake zones 21 days after the occurrence of earthquake.
Results: Among the 37 environmental health activities, 7 activities were the joint ones, which Environmental Health Department had to carry it out with the coordination of other related organizations. In other words, the environmental health has the supervising role in these activities. Totally, such activities had more nonconformities compared with the activities in which environmental health was administered as the main responder. The details of results have been expressed in the full text.
Conclusion: Providing intra-sector coordination, prioritizing the needs of the affected population and considering the principles of community based management in the natural disaster are proposed as the recommendations of this study.
Afsaneh Alinezhadian, Ahmad Karimi, Jahangard Mohammadi, Farzaneh Nikookhah, Mathias Niuman. Anderson,
Volume 6, Issue 3 (12-2013)
Abstract
Background and Objectives: In arid and semi-arid regions, wastewater reuse has become an important element in agriculture. However, irrigation with this resource can be either beneficial or harmful, depending on the wastewater characteristics. The aim of this research was to investigate the soil bacterial and crops quality irrigated with treated wastewater.
Material and Methods: This research was conducted on a maize field near the wastewater treatment plant in Shahr-e-kord in summer,2011. Plots were arranged in a randomized complete block design in 3 replications and 2 treatments, well water (W1) with fertilizer and effluent (W2).
Results: At the end of growth season, soil samples were collected from depth of 0-5 and 5-15 cm and plant samples consisting of old and new leaves and seeds were collected for bacteriological analysis. According to bacteriological analysis, total number of positive lactose bacteria, total and fecal coliforms in depth of 0-5 cm was 42% more than depth of 5-15 cm. In the case of old leaves, total number of coliform and fecal coliform was 88 and 40 MPN/100 mL respectively. Moreover, for new leaves, it was 38 and 2 MPN/100 ml respectively.
Conclusion: According the results, number of indicator bacteria in soil is decreased (about 35%) by passing time.
Mehrnoosh Mohammadi, Alireza Riyahi Bakhtiari, Saber Khodabandeh,
Volume 6, Issue 4 (3-2014)
Abstract
Background and Objectives: Development of cosmetics industry has increased the affinity to use these products by people especially women for makeup and toilet. Due to the presence of metals such as lead and cadmium as preservative and colored element in these products, concentrations of these metals in sunscreen cosmetics, lipstick and hair color were determined. Materials and Methods: Different brands of cosmetics were analyzed to determine Cd and Pb concentration (in µg/kg dry weight) using graphite furnace atomic absorption (AA-670). Results: We found that generally mean concentration of Cd was lower than Pb. There was no significant difference of Cd level between different brands of sunscreen and lipstick (p>0.05), whereas, a significant difference of Pb between the brands studied was observed (p<0.05). No significant difference was obtained between concentration of Cd and Pb in various brands of hair color (p>0.05). Conclusion: Though levels of Pb and Cd in selected brands of cosmetics were lower than standard limits, their low concentration in compared with the results of previous research works could induce serious hazards on human health and the possibility of occurrence or exacerbation of disease including allergy, inflammation, skin diseases, cancer and so on. Hence, preparation and use of these products must be done according to current standards.
Mohamad Hadi Dehghani , Mamood Alimohammadi , Amir Hossein Mahvi, Noushin Rastkari, Masoome Mostofi, Maryam Gholami ,
Volume 6, Issue 4 (3-2014)
Abstract
Background and Objective: Various industries such as petrochemical, oil refinery, pharmaceutical, plastics, paper, steel and, resin produce a substantial of phenol and its derivatives. Wastewaters containing phenol need careful treatment before discharging into the environment due to their poor biodegradability and high toxicity. The objective of this study was to remove phenol by multiwall carbon nanotubes from aqueous solution. Materials and Methods: Adsorption process was implemented in a laboratory-scale batch with emphasis on the effect of various parameters such as contact time (5 to 120 minutes), pH (3- 11), initial concentration of phenol (5 - 50 mg/l) and the sulfate and chloride ions (20 - 200 mg/l) on adsorption process. To achieve a better realization of adsorption process, sorption kinetics and equilibrium isotherms were also determined. Results: The results indicated that maximum adsorption capacity occurred at concentration 50 mg/L and t =30 minutes. The uptake fluctuated very little in the pH range of 3–9, and at greater than 9 the absorption decreased suddenly. Moreover, the presence of sulfate and chloride ions had no effect on the process. It was found that adsorption kinetics and equilibrium data follow a pseudo-second-order kinetics model and a Freundlich isotherm model respectively. Conclusion: It is concluded that carbon nanotubes being effective in a wide range of pH, short time to reach equilibrium and the absence of competing ions on the absorption process can be used effectively in removing phenol from aqueous solution.