Background and Objectives:
handling of food and money contributes to the incidence of food-related public health incidents.
The objective of this study was to determine the total bacterial count and the presence of food borne
bacterial pathogens on Iranian currency notes, collected from food-related shops.
Materials and Methods: A total of 120 Iranian currency notes, comprising notes in four denomination (2000, 5000, 10000 and 20000 R) were collected from various food-related shops including, butchery, bakery, confectionary, fast food, ice cream and poultry meat shop. The currency notes were categorized into three groups according to their physical conditions. All currency notes were examined for total bacterial count, Escherichia coli, Staphylococcus aureus, Bacillus cereus, Salmonella and Listeria according to the standard techniques.
Results: The average number of total bacterial count in four denomination of currency notes (2000, 5000, 10000 and 20000 R) were 118.49, 106.32, 69.44 and 220.81 CFU/cm2, respectively. The association between total bacterial count and denomination of the currency was not statistically significant. Of the 120 currency notes on which bacteriological analysis was conducted 13.3 %, 32.5% and 10.8 % were contaminated with E. coli, S. aureus and B. cereus, respectively. Salmonella and Listeria were not isolated from samples. Currency notes collected from butchery, bakery, confectionary, fast food, ice cream and poultry meat shop were contaminated with E. coli at the rate of 60, 0, 5, 5, 0 and 10 % with S. aureus at the rate of 55, 30, 10, 25, 40 and 35 % with B. cereus at the rate of 0, 10, 20, 5, 20 and 10 %, respectively. There was not a statistically significant association between physical condition and bacterial contamination of the currency notes. The effect of presence or absence of cashier in food-related shops on bacterial contamination of the currency notes was also evaluated.
Conclusion: Money has got the potential to change through many different hands and could be exposed to many different environments at a relatively high frequency. Since there is very little information regarding the hygienic history of any forms of currency, great care should be taken when the same person facilitates the handling of money and the preparation and handling of food to avoid cross contamination.
Backgrounds and Objectives: Domestic sewers and wastewater treatment plants are suitable places for the growth of some types of Cockroaches. Annually the water and wastewater company of Qom city make considerable attempts to overwhelm the problem. The current study is aimed to determine types of Cockroaches and select the optimal methods for their control.
Materials andMethods: In this study, 120 manholes are selected in different locations of Qom city, the numbers of Cockroaches are counted and the Cockroaches are classified into different groups. Then, each group are faced to different insecticides Including Simperator, Diazinon , Dursban Ec, Faikam, Sipermetrin, Icon, Deltametrina and Sulfac. One group of manholes was considered as blank sample during one month. Counting and determination of Cockroaches in these manholes conducted before using insecticides and also five months after it.
Results: the study showed that all sewers were 100% polluted by Cockroaches. The number of Cockroaches in manholes range from minimum 4 to maximum 3600 in each manhole. The applied of insecticides including Dursban Ec, Simperator, Sulfac, Dursban, and Deltametrina are used 2 gr in 100 square meter of area of each sewer. The Cockroaches population reduced to approximately zero after application of these insecticides. Spraying sewers by Simperator controlled 100% of Cockroaches.
Conclusion: the most effective method for the control of Cockroaches was usage of 2 gr of Dursban (Ec) in squaremeter of area in the beginning of warmseason.If we use 1-1/5months interval between the time of spraying insecticide in selected wells, with using simperator and dursban (Ec) we can overwhelm Cockroaches using Simperator and Dursban Ec. The results of statistical analysis show that reduction of number of coackroaches in one month after using poison is significant (P-value< 0.05). But after 5months it lose meaningful in all of them.Also, reduction of number of coackroachesin blank manholes was not statistically significant.
Backgrounds and Objectives:Indusrial noise exposure is the most common hazardous agent in the world.This study has been done to determine the prevalence associated with occupational noise in car smoothers at qazvin.
Materials and Methods: The study group composed of 50 subjects who were selected out of a total of 218 car smoothing workshops.Background information,exposure time and...with a questionnaire collected.Noise exposure and hearing loss were measured by noise dosimeter model CEL-280 and audiometer model OB 288 Madsen.
Results: The mean of age and work experience were 38.7 and 21.5 respectively.Noise exposure and total hearing loss were measured 98.2±3.4 dB(90-104dB) and 22.1±9.16 dB respectively. Spireman correlation was significant between right and left ears(P<0.05 ,R=0.87).Total hearing loss were measured natural(NIHL!25) in 64 percent(32 person),slight(26! NIHL!40)in 34 percent(17 person) and moderate (41! NIHL!60) in 2 percent (1 person).The most and the least hearing loss were measured 42.4(4000 HZ) and 37.1(8000 HZ) dB in left and right ear respectively. The chi square analysis was significant between hearing loss,work experience and age(P=0.015).ANOVA analysis was not significant between noise exposure and hearing loss(P=0.09).
Conclusion:Considering NIHL and severe noise exposure , the necessity for improvement of controlling and protection measures has prime importance.
Background and Objectives: Free living nematodes due to their active movement and resistance to chlorination don't remove in conventional water treatment processes thus can be entered to distribution systems and cause adverse health effects. UV irradiation can be used as a method of inactivating these organisms.
Materials and Methods: This study is done to investigate the effect of ultraviolet lamp on inactivation of free living nematode (Rhabitidae) in water. The effects of duration of irradiation, turbidity, temperature, UV dose and pH are investigated in this study. Ultraviolet lamp used in this study was a 11 watt lamp with intensity of 24 µw / cm2.
Results: Contact time required to achieve 100% efficiency for larvae nematodes and adults were 9 and 10 minutes, respectively. Increase of turbidity up to 25 NTU decreased inactivation efficiency of larvae and adult nematodes from 100% to 66% and 100% to 64%, respectively. Change in pH ranged from 6 to 9 did not affect the efficiency of inactivation. With increasing temperature inactivation rate increased.
Conclusion: The results showed that there was a significant correlation between the increase in contact time, temperature rise and turbidity reduction with inactivation efficiency of lamp)p<0.001(. Also the effect of the lamp on inactivation of larvae nematode was more than the adults.
Background and Objectives: Reuse of treated wastewater in agriculture is becoming more attractive due to the growing demand for water, particularly in arid and semi-arid regions like Iran.In some areas, industrial wastewaters distribute arsenic in the water and vegetables, among the other plants, are mainly irrigated by municipal and industrial wastewater. This study aimed to evaluate the outcome of radish irrigation using water contaminated with arsenic and zinc and to measure the zinc concentration in the edible parts of radish plant. Materials and Methods: The experiments were designed in the form of a factorial completely randomized design with three replications in which radishes were planted in pots about five kilograms. Arsenic concentration at four levels (0, 100,300 and 600 µg/l) and zinc concentration at three levels (0, 10, and 50 mg/l) were added to the irrigation water. The pots were equally irrigated once every 3 to 4 days. After harvesting and laboratory operations, zinc concentration was measured using atomic absorption spectroscopy. Results: The study indicated that zinc concentration in radish tubers is correlated with the concentration of zinc in water. The results of the analysis of variance table for the effect of zinc and arsenic-contaminated irrigation water on zinc concentration in radish roots, tubers and leafs show only one treatment (zinc concentration in water) on the property is significant at 5 and 1%. The results of the comparison table revealed that Zn uptake was decreased with increasing arsenic up to 300 µg/l. Conclusion: It was found that zinc concentration in radish roots, tubers, and leafs is correlated with the concentration of zinc in water. Moreover, there was a competition between the absorption of zinc and arsenic in plants. With increasing arsenic in irrigation water, transition of Zn was reduced to aerial part.
Objective and Background: Fluoride is an element widely found in the earth crust. Advantages and disadvantages of fluoride in the human body are depended on its concentration. Long-term consumption of drinking water contaminated with arsenic can cause adverse health effects such as skin lesions and cancer in humans. The aim of this study was to study efficiency of nano alumina on multi walled carbon nano tube for removal As(V) and fluoride from aqueous solution.
Materials and Method: In this study, nano-scale crystalline alumina was synthesized on single walled carbon nanotube by sol-gel method for using as a sorbent for solid phase extraction of Fluorine ion and arsenic(V). Response surface methodology based on Box-Behnken was used to assess the effect of independent variables on the response function and prediction of the best response value. In this study, effect of different parameters, such as contact time (10 to 120 min), pH (3-9), adsorbent dosage (0.25-1.5 g/L) and initial concentration of fluoride (2-8 mg/L) on efficiency of process was investigated. The structure of nano-scale alumina on multi walled carbon nano tube was determined by XRD and SEM techniques. Moreover, Freundlich and Langmuir isotherm models were used to calculate equilibrium constant.
Results: It was found that by increasing contact time and adsorbent dosage the rate of fluoride removal increased. However, by increasing pH and initial concentration the efficiency of fluoride removal decreased. High value for R2 (0.94) shows that removal of arsenic(V) can be described by this model. The Freundlich isotherm was the best fitted graph for experimental data with R2 more than 0.997.
Conclusion: In this study, it was observed that efficiency of arsenic(V) and fluoride removal was greatly increased by using nano-scale alumina on multi walled carbon nanotubes (MWCNTs).
Backgrounds and Objectives: Quantity of trace metals in the wet precipitation can illustrate the environmental pollution of different urban areas. Up to now, there is no study regarding the chemistry of wet precipitation in Tehran .The objectives of this study are: measurement of heavy metal concentrations and identification of the main factors affecting the heavy metal concentrations in wet precipitation using factor analysis method.
Materials and Methods: This was a cross-sectional study in which measurements of heavy metals were performed in 53 wet precipitation samples collected from a central site of Tehran City, capital of Iran. The samples were collected during November to May in 2010, 2011 and 2012 on the roof of the student’s dormitory building of Tehran University of Medical Sciences and then the concentration of heavy metals in each sample was measured with ICP-MS.
Results: pH ranged from 4.2 to 7.1 with a mean value of 5.1 indicating in acidic range. Result of EF calculations revealed that samples were not enriched with Fe and Cr but were enriched with Zn, Cd, Ni, Pb and Cu. Factor Component Analysis with Varimax normalized rotation showed Al, Fe and Cr are originated from crustal source and Zn, Cd, Ni, Pb and Cu are originated from anthropogenic sources.
Conclusion: EF and acidic pH values indicate Tehran is under the influence of extremely anthropogenic activities. Large number of vehicles and industrial activity in the city are undoubtedly responsible for the emission of a wide range of pollution.
Background and Objective: Malaria is a disease affecting 300–500 million people in tropical and subtropical regions and causes approximately 2.7 million deaths annually. Currently, no vaccine protects against malaria and resistance to anti-malaria drugs such as chloroquine is increasing and spreading geographically. Moreover, anti-malarial drugs are expensive and often unaffordable to low-income populations. A better understanding of the relationship between the El Niño Southern Oscillation (ENSO), the climatic anomalies it engenders, and malaria epidemic could help mitigate the world-wide increase in incidence of this mosquito transmitted disease. There is evidence of a relationship between climate variability and the transmission of mosquito-transmitted diseases. Therefore, in this study we intended to analyze the relationship between ENSO events and annual malaria occurrence (AMO) in Iran to assess the possibility of using ENSO forecasts for improving malaria control.
Martials and Methods: Two types of data were used: The data of annual malaria incidence in Iran were collected from the national and international reports of malaria occurrence in Iran; the annual malaria occurrence data for 38 years (1974-2013) were collected from related sources. ENSO is a cyclic phenomenon, which its frequency is 2 to 7 years (i.e., irregular) and is the second strongest natural driver of climate variability, the first being normal seasonal variability. This oscillation has two different phases: a warm episode known as El Niño; and a cold episode called La Niña, where warm and cold refer to the direction of departure from average of the equatorial Pacific Sea surface temperature (SST), a fundamental indicator of the ENSO state. The Pearson correlation analysis at 0.95 confident level (P-value=0.05) on monthly timescale was used in order to understand the relationship between ENSO and annual malaria occurrence in Iran. The 2-tailed independent parametric T-test was used knowing that whether there is a significant difference between the La Nina years occurrence and El Nino years occurrence.
Results: The results indicated that a slight negative association could be detected between ENSO and annual Malaria occurrence in Iran. Our finding showed that the detected correlation between monthly ENSO and annual malaria occurrence is statistically significant only in months October and May while no significant relationship between ENSO and AMO at 0.95 confident level was found for other months.. The inverse relationship between ENSO and AMO means that the years having higher malaria occurrence coincides with the warm ENSO phases or EL Nino episode while the years having lower malaria occurrence coincides with the cool ENSO phases or La Nina episode. In El Niño episode, the annual occurrence of malaria is about 0.2 to 0.3 higher than La Niña episode years.
Conclusion: The positive association between El Niño and rainfall of Iran resulted in higher occurrence of malaria by proliferation of Anopheles mosquito especially in southern and southeastern region of Iran.
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