فهرست مطالب
International Journal of Environmental Health Engineering
Volume:3 Issue: 3, Aug 2014
- تاریخ انتشار: 1392/08/13
- تعداد عناوین: 15
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Pages 1-7Aims
The purpose of this study was to investigate the composition of dental waste coming from six dental health services in Isfahan, Iran.
Materials and MethodsFrom 45 public dental clinics in Isfahan, six public dental health services were selected (three dental clinics and three dental centers). Waste collection took place from October to December 2011. During this period, three samples were collected from each dental clinic and were divided to pre-determined groups manually.
ResultsIn dental centers, the amount of infectious, non-infectious and domestic-type waste accounting for 45.07%, 12.15% and 42.78%, respectively. Whereas in dental clinics the production rates of infectious, non-infectious and domestic-type waste accounting for 52.2%, 8.58% and 39.22%, respectively.
ConclusionOverall, according to the results it can be said that integration of infectious and hazardous waste with general waste leads to the amount of infectious waste appears much greater than it actually is. The collection and disposal of amalgam and other hazardous dental solid waste should be regulated as soon as possible and to decrease the costs of dental waste management the uncontaminated recyclable items, which contained approximately 33% of total dental waste should be recycled or reused if possible.
Keywords: Amalgam, dental clinics, dental solid waste, infectious waste, public dental services, solid waste management -
Pages 8-12Aims
The aims of this study was determination of driver behavior in car accident and analyzing the relationship between state anxieties (SA) with subscale of driving behavior.
Materials and MethodsThe self-reporting of the drivers was determined by using Manchester driving behavior questionnaire (DBQ) and Spielberger statetrait anxiety inventory in 168 drivers who had a crash while driving.
ResultsIndependent t tests showed that violations (ordinary and aggressive) are the most common behavior in drivers, Pearson's correlation revealed that SA had a significant direct positive relationship with lapses (P < 0.01) and error subscales (P < 0.05), also Pearson's correlation showed that age had a negative significant relationship with factors of DBQ.
ConclusionIt can be concluded from the results (according to the relationship between SA with error and lapses factor) that SA is destructive and affects the memory performance and mental process in the drivers and causes absent mindedness and imperfect memory function and process in these people during driving.
Keywords: Driving behaviors, drivers having crash, state anxiety -
Pages 13-18Aims
The first aim of this study was to estimating the percentage of land area that was affected by various levels of light pollution and secondary aim is to assess the light pollution growth.
Materials and MethodsThis study describes a methodology for modeling light pollution in Bojnord city, using geographical information systems and remote sensing technology. The Defense Meteorological Satellite Program-Operational Linescan System (DMSP-OLS) and Landsat TM5 images in 1991, 1999, 2005 and 2012 were used. The DMSP-OLS images were classified to six categories from null to very high. The Landsat images were applied in order to calculate the urban area and extraction urban border in 4 years.
ResultsThe results were showed that the light pollution area (km2) in very high category has increased 10.34, 2.73 and 15.94 km2 of the entire study area from 1991-1998, 1998-2005 and 2005-2012, respectively. While, in that periods of time, the null category area (km2) declined 23.19, 21.97 and 100.36 km2, respectively. In 2005 and 2012 about 92.8% and 86% of the total study area has been in the Null class. There was a direct association between urbanization, spatial development of urban areas and light pollution growth.
ConclusionsOne of the main reason for light pollution growth is declaring this region as capital city in 2005 and consequently, urban development and population emigration to capital.
Keywords: Bojnord, Defense Meteorological Satellite Program-Operational Linescan System geographical information systems, light pollution, urbanization -
Pages 19-23Aims
This study was conducted to determine the prevalence rate, virulence genes and antimicrobial resistance of Escherichia coli O157:H7/NM isolated from hamburger and chicken nugget in Isfahan, Iran.
Material and MethodsFrom June 2013 to July 2013, a total of 190 hamburger (120) and chicken nugget (70), were collected from four randomly selected factories in Isfahan, Iran. They were evaluated for the presence of E. coli O157:H7/NM using microbiological culture and polymerase chain reaction. Statistical analysis was performed using SPSS software version 16.0 (SPSS Inc., Chicago o, IL, USA).
ResultsFrom a total of 190 samples analyzed four samples (2.1%) were contaminated with E. coli O157. All of the E. coli O157 were isolated from hamburger samples (3.3%) and chicken nugget samples were negative. Of four E. coli O157 isolated, only one sample was serotype E. coli O157:H7 and others were serotype E. coli O157:NM. Among four E. coli O157:H7/NM isolates, one strain was positive for all stx1, stx2, eaeA and ehxA genes. One strain was positive for stx2 gene. The other two were negative for these genes. All isolates (100%) were resistant to one or more antimicrobial agents.
ConclusionsThe results of this study showed that hamburger could be a significant source of E. coli O157:H7 and E. coli O157:NM serotypes in Iran and multi-resistance was found in 27% of E. coli O157 strains and this is a major public health concern.
Keywords: Antimicrobial resistance, chicken nugget, Escherichia coli O157:H7, NM, Hamburger, virulence genes -
Pages 24-29Aims
This research was conducted to investigate the efficacy and feasibility of ozone-hydrogen peroxide advanced oxidation process as a post-treatment step of composting leachate treated by an anaerobic migrating blanket reactor biological treatment system.
Materials and MethodsLeachate samples was collected from the effluent of the biological treatment system and used in an ozone reactor after dilution. The effectiveness of the pH values (4.5-11.5), H2O2 concentrations (0.5-4 g/L), ozone doses (0.2-1 g/h) and reaction times (5-270 min) were evaluated to determine optimum operational conditions.
ResultsThe highest removal efficiencies were achieved 72% and 79% for chemical oxygen demand (COD) and biochemical oxygen demand5 (BOD5), respectively, at pH 8.5, 2.5 g/L H 2 O 2 concentration, and 1 g/h ozone dose, during 270 min reaction time. Furthermore, results indicated that the BOD 5 /COD ratio was decreased from 0.53 to 0.4 after 270 min reaction time.
ConclusionsThe O 3 /H 2 O 2 was found to oxidize preferably COD and BOD 5 of the leachate samples. In consequence, a decrease in the biodegradability of leachate was observed after oxidation treatment. The O 3 /H 2 O 2 reaction proved to be a feasible technique for the oxidation of the leachate under study, and it can be considered a suitable treatment for this type of wastewater.
Keywords: Biochemical oxygen demand5 removal, chemical oxygen demand removal, composting leachate, O3, H2O2 reaction -
Pages 30-37Aims
The aim was to study the indoor air quality (IAQ) levels inside the governmental elementary schools of Dammam City in Kingdom of Saudi Arabia (KSA) and study factors affecting these levels.
Materials and MethodsSixteen schools were selected for this study; 12 of them were representing governmental constructed buildings, while the other 4 schools were representing rental buildings. Levels of dust or total suspended particulates (TSP), carbon monoxide (CO), carbon dioxide (CO 2 ), nitrogen dioxide (NO 2 ), sulfur dioxide (SO 2 ), and benzene; in addition to temperature degree and relative humidity percent were measured during this study at four selected locations inside each school and one location outside it.
ResultsThe highest levels of all pollutants were found inside classrooms that were located directly on the moderate traffic streets compared with low or very low traffic activity ones. Levels of most air pollutants inside the governmental constructed buildings were higher than those inside the rental type of schools.
ConclusionThe average levels of TSP, NO 2 and CO inside all selected schools were lower than the air quality guidelines (AQGs). In contrary, all mean levels of CO 2 and nearly 50% of SO 2 and benzene levels were higher than their AQGs. Increasing the efficiency of the mechanical and air condition systems inside classrooms is important for appropriate ventilation and improving IAQ level.
Keywords: Adverse Effects, air quality guidelines, elementary schools, indoor air quality, school environment -
Pages 38-44Aims
The study was done to find out the types of injuries, modes of road traffic accidents and case fatality rate of road traffic accident cases from 1 st April 2005 to 31 st March 2010 in a tertiary care hospital.
Materials and MethodsThe retrospective study conducted on hospitalized patients admitted with road traffic accidents in a tertiary care level from 1 st April 2005 to 31 st March 2010. Data collected from the registers maintained in the medical records department, follows the guidelines of International Classification of Diseases-10 coding.
ResultsOf the 7,660 road traffic accident cases reported in a hospital from 1 st April 2005 to 31 st March 2010. Most of the cases and deaths were occurred in the age group of 15-44 years. Total deaths occurred due to road traffic accident was 249 (3.25%). Motorcycle rider injured in road traffic accident was more except other land transport accidents during the period from 2005 to 2010. Of the road traffic accident cases, fractures (42.7%) were more than superficial injuries (18.56%) and dislocations (2.6%).
ConclusionThis study mentioned that most of the cases and deaths were occurred in 15-44 years. Accidents of the economically productive people will affect their family. Hence to reduce the road traffic accidents by conducting public awareness program and strict enforcement of traffic rules.
Keywords: Accident, Female, Male, road, traffic -
Pages 45-52Aims
The aim of this study was to find out the vulnerability of school children affected by roadside vehicle noise.
Materials and MethodsThe noise levels were measured in three time zones: 10.45 and 11.45 am, 12 and 1 pm, and 2 and 3 pm. A self-made interview schedule was constructed for getting feedback from the teachers and students about the problems associated with the teaching - learning process. The different percentile values L 10, L 50 , L 90 were used for the evaluation of noise climate (NC), equivalent noise level (Leq), transport noise index, and noise pollution level (L NP ).
ResultsThe results revealed that the average distance of the roadside school situated in urban area (9.4 feet) was much less than in rural area (14.4 feet). The average number of vehicles in rural areas was much less than in urban areas. The study also demonstrated that out of five varieties of vehicles, only heavy vehicles like bus and trucks produce intense noise (85-90 dB). Although air siren of train has a very high noise, which range from 90 to 115 dB, other varieties of light vehicles also produced noise ranges from 76 to 90 dB. The average noise meter reading clearly indicates that lesser the distance from the roadside, higher is the noise intensity.
ConclusionResults revealed that not all schools, particularly those schools that are very close to the roadside, are intensely affected by such high pitch noise and subsequently teaching - learning process were also greatly affected by such activities. Therefore, it is highly recommended that village committee and municipality authority should coordinate with the school authority for taking measures for such irreversible damaged.
Keywords: Heavy vehicles, light vehicles, noise, road side school, School children -
Pages 53-57Aims
The object of this study was to assess the usefulness of the H 2 S test for detection of fecal pollution of water in comparison to fecal indicator bacteria (FIB).
Materials and MethodsA total of 70 raw water samples were collected from drinking water sources in Isfahan province of Iran, aseptically in sterile containers during May-October 2012.The modified H 2 S test medium of Manja et al. was used except that L-cysteine was added as an additional medium component. Total coliforms (TCs), fecal coliforms (FCs), and fecal streptococci (FS) were also estimated by multiple-tube fermentation method. Statistical analyses were carried out using SPSS 20 at the 95% confidence level (α = 0.05).
ResultsIt was found that out of 70 water samples assessed, 48.3%, 30.0%, 34.6%, and 32.9% of the samples were positive for TCs, FCs, FS, and H 2 S, respectively. Analysis of data showed that 95.6%, 69.5%, and 76.9% of water samples, which were positive for H 2 S test were also positive for TCs, FCs, and FS, respectively. The H 2 S test was found to have the highest accuracy for the detection of FS, but it was not a suitable indicator for the prediction of FCs.
ConclusionsOur results showed that H 2 S test is not a suitable alternative approach for routine water quality monitoring. However, the H 2 S test could be used as an easy and economic test to assess the quality of drinking water in communities where manpower and sophisticated equipment are inadequate. More laboratory and field studies are required to assess the reliability of the method as an alternative method of traditional indicators.
Keywords: fecal indicator bacteria, H2 S test, Microbial quality, water sources -
Pages 58-69Aims
The aim of this study was to determine water softening behavior of Iranian natural zeolite and blast furnace slag (BFS) as materials of slow sand filters (SSFs) in small communities' water resources.
Materials and MethodsThree filters setups were prepared from the plexiglass tubes each by 9 cm inner diameter and 120 cm height. The used filter media were included conventional sand, BFS and Iranian natural zeolite. The filtration rate was adjusted between 0.1 and 0.24 m 3 /m 2 /h and hence that the flow rate of each filter was 1.5 L/h. Turbidity, total hardness and EC of water samples were analyzed before and after the treatment process according to standard methods.
ResultsThe mean turbidity removal efficiencies in the studied filters were 98.82%, 98.98% and 98.97% for conventional SSF, slag modified filter (SMF) and zeolite modified filter (ZMF), respectively. The mean EC reduction efficiencies in SSF, SMF and ZMF also were similar and were 9.99%, 11.02% and 10.73%, respectively. The mean total hardness removal efficiencies in SSF, SMF and ZMF were 21.19%, 51.95% and 66.3%, respectively.
ConclusionsIt is concluded from this study that modified filter media, SMF and ZMF, are very good options for total hardness and turbidity removals in communities that have some problem with this parameter.
Keywords: Hardness, modified slow sand filter, physicochemical quality, water resources -
Pages 64-70Aims
The aim of this study was to compare the concentration of volatile organic compounds in administration rooms of the hospital.
Materials and MethodsThe present study assessed indoor concentration levels benzene, toluene, ethyl benzene and xylene (BTEX) in eight hospitals of Yazd province from January 16 to February 25 of 2012. Management, accounting and personnel rooms were selected as sampling units. Samples collected in three sequential daytimes by Tedlar bag. Gas chromatography-flame ionization detector method was applied for analysis of the component.
ResultsTotal BTEX concentrations were relatively below (<10 μg/m 3 ) in all hospitals. There was no significant difference in amounts of the compounds among studied parts, except for benzene (P < 0.05). According to sampling units, the mean of BTEX component concentrations (in units of μg/m 3 ) were for benzene 1.03 ± 1.21, toluene 0.96 ± 1.79, ethyl benzene 0.78 ± 1.92 and xylene 0.86 ± 0.73, respectively.
ConclusionThe accounting unit showed highest concentrations of BTEX that its possible due to usage of the numerous numbers of electronic devices (computers, printer and copier), official supply (ink varnish, adhesive, etc.) and the air-conditioner.
Keywords: benzene, toluene, ethyl benzene, xylene, gas chromatography, hospital, indoor air, office building, solid phase micro extraction -
Pages 71-75Aims
The purpose of this study was to determine of nitrate and nitrite exposure and their health risk assessment in 21 brands of bottled waters in Isfahan's market in 2013.
Materials and MethodsThe samples bought from shops in Isfahan city and were analyzed for nitrate and nitrite. The measured concentration of nitrate and nitrite were compared with the labeling data and codex guideline values. Statistical analysis on data was performed with the Kolmogorov-Simonov non-parametric test, the paired t-test and the student's t-test at P < 0.05 of confidence level. The health risk was assessed through chronic daily intake (CDI) and hazard index (HI).
ResultsThe mean concentrations ± standard deviations based on statistical t-test for nitrate and nitrite were 1.42 ± 0.55 and 0.02 ± 0.015 mg/l, respectively. Based on results nitrate concentrations have a statistically significant difference with labeling values. There was no labeling value for nitrite on the samples. The amounts of CDI for nitrate and nitrite were 1.5E-04 and 3.3E-04 mg/kg/day, respectively and their related HI was same and below 1.
ConclusionAccording to the results of the present study, nitrate and nitrite levels in the studied bottled waters were not found in concentrations considered hazardous in terms of public health. The label values not provide reliable data for consumer. The health risk of bottled water consumers from nitrate and nitrite exposure in Isfahan were in the acceptable range.
Keywords: Bottled water, brand, health risk assessment, nitrate, nitrite -
Pages 76-81Aims
The aim of this study is to determine the impact of relative humidity (RH) and contaminant concentration on photocatalytic conversion of gaseous toluene by using TiO 2 coated on nickel foam.
Materials and MethodsTiO 2 nanoparticles were prepared by the sol-gel process and coated on nickel foam. Structural and morphological characteristics of nanoparticles were determined using Scanning electron microscope, X-ray diffraction analysis. Photocatalytic conversion of gaseous toluene at the different levels of RH and toluene concentration was measured under ultraviolet-A radiation by gas chromatograph with Flame Ionization Detector.
ResultsAfter being fixed the contaminant concentration, 30% level of RH had the most impact on the photocatalytic efficiency, 10, 0,5 0 and 80% levels of humidity had, in turn, the most impact. Results also showed that TiO 2 nanoparticles coated on nickel foam at the concentration of 20 ppm had the most efficiency of photocatalytic conversion. After that, the most efficiency was recorded at the 10 and 50 ppm concentrations, respectively.
ConclusionBased on the results, the photocatalytic conversion of gaseous phase toluene by TiO 2 coated nickel foam is increased with the increase of RH to a certain level; beyond that the conversion efficiency is decreased gradually due to the saturation of photocatalyst surface and decrease in nanoparticle activity. Furthermore, photocatalytic conversion of gaseous toluene is decreased with the increase of toluene concentration.
Keywords: Concentration, nickel foam, Photocatalyst, relative humidity, TiO2, toluene -
Pages 82-89Background
Road traffic crashes are a huge public health and development problem in Ethiopia. Its current situation requires a high level political commitment, immediate decisions and actions in order to curb the growing problem.
Materials and MethodsData on fatalities, total and partial permanent injuries, and lost workday attributable to vehicle crashes were collected from North Gondar Traffic Offices from 1996 to 2011. Holt and Brown exponential smoothing techniques were used to model the number of fatalities and other injuries due to vehicle crashes.
ResultsThere were 2300 vehicle crashes that occurred from 1996 to 2011 causing an estimated 968 fatalities, 1665 lost workday and 1185 permanent total and partial injuries, and 1,899,950.60$ losses. Only 7.6% of the vehicles had problems before the crashes occurred while 89.9% had no problems. The mean time of crashes occurred were 12.78 h with a standard deviation of 4.19 h. The highest daily, monthly, seasonal, and yearly crashes occurred were during Friday, January, winter and 2009, respectively. Future forecasts showed that by 2015, there could be 414 fatalities, 1123 lost workdays and 438 permanent total and partial injuries, and 955,249.12$ losses.
ConclusionThe numbers of lives lost and disabilities due to vehicle crashes indicated an upward trend in the last decade showing future burden in terms of societal and economic costs threatening the lives of many individuals. Surveillance systems that could enable to monitor patterns of vehicle crashes with preventive strategies must be established.
Keywords: Economic loss, fatal injuries, forecasts, Trends, vehicle crash -
Pages 90-94Aims
The aim of this study was to evaluate the photocatalytic processes for cadmium (Cd 2+ ) and lead (Pb 2+ ) removal at continuous and batch system.
Materials and MethodsThis study was performed at laboratory scale. The reactors used in this study consisted of three parts: Ultraviolet (UV) source, reaction cell, and mixing chamber. The experiments were carried out in a batch and continuous reactor for synthetic wastewater. The concentration of Cd 2+ and Pb 2+ was constant (25 mg/L) in all experiments and effect of titanium dioxide (TiO 2 ) dose, pH, and air dispersion was investigated on the removal efficiency.
ResultsThe results showed that with increasing TiO 2 dose and pH, the cadmium and lead removal increase. The maximum removal of cadmium and lead was obtained in TiO 2 dose 0.9 g/L and pH: 11 that were equal to 99.8 and 99.2% respectively. Furthermore, when air dispersion increased, the removal efficiency increased; while in the air dispersion 2 cm 3 /L the removal efficiency was maximum (88 and 93.2% at the contact time 56 min for Cd 2+ and Pb 2+ , respectively).
ConclusionAccording to these results the TiO 2 has been considered as photocatalyst is the separable and recyclable, so UV/TiO 2 process is an environment friendly process for toxic metal removal.
Keywords: Advanced oxidation, batch, continuous system, heavy metals, titanium dioxide nanoparticle