Showing 12 results for Alimohammadi
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.
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.
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.
N Farajvand, M Alimohammadi,
Volume 7, Issue 1 (7-2014)
Abstract
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.
M Zare Jeddi, N Rastkari, R Ahmadkhaniha, M Alimohammadi, M Yunesian,
Volume 8, Issue 1 (8-2015)
Abstract
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.
A Heidari, R Nabizadeh, M Alimohammadi, M Gholami, A.h Mahvi,
Volume 8, Issue 1 (8-2015)
Abstract
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.
L Karam, M Alimohammadi, L Yadegarian,
Volume 11, Issue 2 (9-2018)
Abstract
Background and Objective: Climate change in recent years has led to a crisis of drought in many countries around the world, including Iran. In such a situation, the supply of safe drinking water is very important and knowing the climate impacts on the chemical quality of these resources can play a significant role in their proper exploitation.
Materials and Methods: Using GIS geomorphology models, the effect of climatic factors including minimum and maximum temperatures, mean precipitation, evaporation, transpiration and vegetation index on the quality of groundwater resources of Varamin Plain include pH, electrical conductivity, total dissolved solid, anions and cations concentrations and total hardness were studied and their maps were produced. Correlation between these factors was investigated using spatial correlation analysis tool at a confidence level of 0.95 (p = 0.05).
Results: The results showed that these parameters (except pH) along the plain are highly variable and the spatial distribution of data in this region is not normal around the mean, and the frequency of pixels with values less than the spatial mean of the region is higher. Spatial distribution of the factors showed that their amounts (except pH) are low in the central area of the plain and reach its peak in the western and northwest regions. The spatial distribution of pH was almost uniform in all the plain.
Conclusion: Correlation analysis showed that the quality of water resources is influenced by climatic factors and the maximum temperature has the highest impact.
S Abolli, M Alimohammadi, M Zamanzadeh, K Yaghmaeian, M Yunesian, M Hadi, Z Soliemani,
Volume 12, Issue 3 (12-2019)
Abstract
Background and Objective: Surface water and underground water quality in countries that facing dehydration have increased the interest of the community to use Household Water Treatment devices. The aim of this study was the evaluation of the quality of drinking water of Household Water Treatment devices and general distribution network in Garmsar, which is under the control of the water safety plan.
Materials and Methods: A descriptive cross-sectional study administered in 6 regions and 41 cities of Garmsar city in spring and summer seasons in 2018. Chemical tests performed according to the standard methods for the examination of water and wastewater, general measurements were performed using the multi-tube fermentation method and counting of heterotrophic bacteria by pour plate method. The results analyzed by using Excel and SPSS software.
Results: The average values during two seasons were reported as: EC= 1507 (μS/cm), TDS= 786.8 (mg/L), F= 0.048 (mg/L), residual free chlorine= 0.67 (mg/L), pH=7.9, total coliform= 0.16 (MPN/100 mL), fecal coliform= 0.14 (MPN/100 mL) and HPC= 112 (CFU/mL). No significant difference found between the chemical and microbial parameters in the general distribution network and the output of the Household Water Treatment devices during the two seasons.
Conclusion: Household water treatment devices did not affect the microbial burden but caused a change in the amounts of some chemical parameters. Drinking water from the distribution network, with the proper application of the water safety plan, is of good quality.
O Nasri, M Yunesian, M Alimohammadi, N Shalyari, S Masoomi, M Shamsipour,
Volume 12, Issue 4 (2-2020)
Abstract
Background and Objective: Regular use of household cleaning products and cosmetics can result in adverse consequences for human health. Therefore, the knowledge of consumption pattern of these products can help to evaluate the effects and finally control the consequences of their inappropriate application. As there is not an appropriate tool for evaluating public use-pattern for these products in Iran, we studied the reliability and validity of a questionnaire designed for the use-patterns of these products.
Materials and Methods: In the present study, a questionnaire, which was previously applied in similar studies for this purpose, was first translated to Persian. Then, some changes were made in the questionnaire according to the studied population. In the next step, the assessment of both content validity and face validity of the instrument was performed. Finally, the questionnaire reliability was studied in two test-retest steps at a 14-day interval with 40 subjects older than 14 years old being resident in Tehran city.
Results: Total Content Validity Index (CVI) of this questionnaire ranged 0.66-1 for all question items. Cronbach's alpha coefficient was 0.814. The correlation assessment of each question item based on the total correlation score showed that all questionnaire items had a direct and strong correlation with the total instrument score.
Conclusion: Given the acceptable validity and reliability obtained for the questionnaire in Persian in this study, it can be used in those investigations that evaluate use patterns or asses the exposure risks to chemical pollutants from cosmetic products or detergents.
Mehrnoosh Abtahi, Mahmood Alimohammadi, Reza Saeedi, Ramin Nabizadeh, Masoomeh Askari, Babak Mahmoudi, Maryam Ghani,
Volume 14, Issue 2 (9-2021)
Abstract
Background and Objective: The aim of this study was to evaluate the chemical and microbial quality of bottled water in Iran and to calculate the water quality index (WQI).
Materials and Methods: Different brands of bottled water (4 samples from 71 brands) were randomly collected from the market. Chemical and microbial characteristics of the samples were examined and determined. Finally, the calculations related to the WQI index were performed and the water samples were classified as excellent, good, poor, very poor and unsuitable.
Results: None of the samples exhibited concentration of heavy metals beyond Iranian water standards, and the concentration of sulfate (SO4), chloride (Cl) and fluoride (F) did not exceed international standards. However, in some samples, nitrite (NO2) and nitrate (NO3) concentrations were higher than recommended standards. With Regard to other water quality parameters, 8% to 89% of the samples exhibited concentration higher than the values provided on the water bottle label. 5 species of different bacteria were found in 15 water samples. According to the WQI index, about 63% of the samples were of excellent quality. Also, the water quality of 34% and 3% of the samples fell in good and poor quality categories, respectively. None of the bottled water samples was of very poor quality.
Conclusion: The quality of bottled water investigated in this study was generally suitable, but due to the wide range of bottled water in Iran based on brand and seasons, continuous evaluation of water treatment methods in companies and careful monitoring of chemical and microbial quality of bottled water in all seasons is recommended.
Farideh Mostafaei, Mahmood Alimohammadi, Masud Yunesian, Zahra Tayebi,
Volume 14, Issue 4 (3-2022)
Abstract
Background and Objective: Outsourcing services to the private sector can be a step towards achieving the goals of community health promotion, job creation, better access to health services, and improving the quality of health services. In this regard, health service offices were established in Tehran to improve the health status of food preparation, distribution and sale centers and increase food safety based on government approval. This study aimed to evaluate the roles of health services offices on environmental health indicators.
Materials and Methods: In this descriptive-comparative study, nine health service offices supervised by Tehran University of Medical Sciences (located in South Tehran Health Center, Eslamshahr city, and Shahr-e Rey) were surveyed. Seven environmental health indicators measured in the years before the establishment of these Health Service Offices (2015-2017) were compared with those obtained after their establishment (2018-2019). The indicators data were analyzed using Excel, SPSS software, and statistical tests.
Results: The result showed no significant difference in public places and centers for food preparation and distribution offenders, public places with health criteria, percentage of employees with a health training certificate, health care, and percentage of inspection coverage before and after establishment of health service offices (p >0.05). However, the relationship between the food preparation indicators and distribution centers with health criteria and public places and closed food preparation and distribution centers were significant (p > 0.05).
Conclusion: This study is one of the first researches conducted to evaluate the effectiveness of health services offices on health-safety indicators in Iran. Therefore, more comprehensive monitoring and studies should be done to evaluate these offices' performance quality and their related cost-benefit analysis.
Afsaneh Askari Zade Haghighi, Samaneh Abolli, Mahmood Alimohammadi,
Volume 15, Issue 1 (4-2022)
Abstract
Background and Objective: barbershops are one of the most important public places for beauty activities, which requires attention to health issues (personal and environmental), and non-compliance with health standards and procedures can be a threat to public health. The level of awareness and performance of employees can affect the management of waste production. This study aimed to investigate the level of knowledge of personnel about waste production and performance in southern Tehran in 2021.
Materials and Methods: This descriptive cross-sectional study was conducted in southern Tehran with a statistical sample of 330 places. In this study, a questionnaire was used which comprised of three sections; demographic information, the level of awareness and performance of personnel, and the information was completed after interviews with hairdressers. Data were analyzed by Kolmogorov-Smirnov, Chi-square, Pearson correlation coefficient, one-sample t-test, and Mann-Whitney using SPSS software (IBM-v.26).
Results: The average scores of awareness and performance of individuals in waste management were 43.18 and 48.27, respectively, and based on the results of qualitative analysis, the scores of awareness and optimal performance of individuals in waste management were 53.6% and 72%, respectively. Also, 46.6% and 28% of the participants obtained unfavorable scores on knowledge and practice in waste management, respectively. People's knowledge about the management of waste produced in hairdressers had a significant relationship with gender, history of health education, history of health crimes, education and performance of people about the management of waste produced in hairdressers with gender and history of health education. There was no significant relationship between knowledge and practice with other variables.
Conclusion: Barbershop is a place where paying attention to environmental health is effective in promoting community health and disease control. Ignoring this issue can lead to the spread of various diseases. In general, the results of this study showed that the level of awareness is effective in the performance of barbers regarding the management of waste production. Additionally, health education was known effective in the level of awareness and performance of hairdressers in this field, so the improtant roles of these variables should taken into consideration.
