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Background and Objectives: Waste produced by health and treatment centers (hospitals) including medical diagnostic laboratories is one of the sources of municipal waste production. Waste produced by medical diagnostic laboratories due to the existence of pathogens and infectious materials by high importance is one of the environmental issues. This survey has been done on the qualitative-quantitative analytical bases, and the investigation has focused on the management strategies of the waste material of medical diagnostic laboratories of Rasht, Iran in 2009. Methods: In this descriptive study, samples were collected from 19 medical diagnostic laboratories of Rasht in 3 consecutive days (Monday, Tuesday and Wednesday every week), after filling the questionnaire and interviewing with the managers. Then, the samples were separated manually, and divided into 46 different constituents and weighed. Next, the constituents were classified based on characteristics and potentiality of being hazardous.Results: The total amount of annual waste production by the medical diagnostic laboratories of Rasht is 25785.143kg. In this study, the share of manufacturing conventional waste (domestic type wastes), especially infectious, chemical, pharmaceutical, and radioactive wastes were 1.16%, 95.34%, 1.42% and 2.08%, respectively. The highest and lowest amount of waste production relates to plastic materials and wood which are 48.37 and 0.43%, respectively. In this study sharp cutting things were calculated to be 10.52%. Furthermore, 84 percent of the managers of the medical diagnostic laboratories had not had enough information of the circulars and instructions on the enforceable management strategies of the medical wastes.Conclusion: Concerning the management of the medical waste production in the medical diagnostic laboratories, it is suggested that the managers and the personnel be trained on the separation, collection, and disinfection techniques and final disposal, and the wastes have to be treated per regulations and instructions.

Background and Objectives: Horizontal roughing filters (HRF) can properly remove suspended solids and microorganisms from surface water resources, especially on filtration rates less than 1.5 m/h. This research was aimed at suspended solid removal efficiency of HRF during secondary wastewater effluent filtration. Methods: This experimental study was conducted by installing an HRF pilot system on effluent pumping station of Qom wastewater treatment plant based on aerated lagoon process. The pilot was a horizontal cylindrical column consisting of three compartments filled with river gravels in various sizes. Grab samples were simultaneously taken from HRF inlet and outlet in three filtration rates: 0.5, 1, and 1.5m/hResults: The results indicated that filtration rate had a significant effect on the amount of total suspended solids in HRF effluent. During optimum operation of HRF, removal efficiencies of three filtration rates (0.5, 1, and 1.5 m/h) were 78.5, 63.1, and 66.9, respectively.Conclusion: T-test analysis indicated that with a significance difference, outlet effluent from HRF in all three flow rates met the standard requirements of Iran Environmental Protection Agency for irrigation and discharge to surface water.

AbstractBackground and Objectives: Fungi spores can be found everywhere. The amount and variety of fungal spores and their vast spread could be a preliminary step to the initiation of different diseases in people with different levels of health.Methods: In the present study six wards including nephrology, internal ward for women, surgery ward for men, operating theater for E.N.T., ophthalmology, infectious diseases ward and the laboratory were chosen for sampling on the basis of their types of activities and their in-patients. We used Anderson sampling method, collected samples within two minutes with flow rate of 28.3 L/Min in sabouraud medium.Results: Maximum contamination in the infectious diseases ward was 300 CFU/m3 and minimum contamination in E.N.T. was 94 CFU/m3. The maximum percentage of fungal spores in the hospital air was observed to be as follows: penicillin with 36.36%, Cladosporium 24.74%, A.niger 17.97%, Rhizopus 10.57% and A.flavus 2.74A%.Conclusion: Fungal contamination concentration in hospital indoor air in this study was higher than the recommended limits and other similar studies from a quantitative point of view, but it was similar to other studies in terms of identified species.Keywords: Air Pollution, Indoor; Fungi; Sampling; Cross Infection; Qom, Iran.

"nBackground and Aim: Today, one of the most important environmental issues is dental solid wastes which are of great importance because of the presence of hazardous, toxic and pathogen agents. In this survey, solid waste produced in Hamedan general dental offices is evaluated. "nMaterials and Methods: In this descriptive study, from 104 general dental offices in Hamedan , 10 offices were selected in simple random way. From each offices, 3 sample at the end of successive working day (Sunday, Monday and Tuesday) were analyzed. Samples were manually sorted into different 74 components and measured by means of laboratory scale. Then, measured components were classified in the basis of characteristic and hazardous potential as well as material type. "nResults: Total annual waste produced in general dental offices in Hamadan is 14662.67 Kg (9315.45>95.0% Confidence Interval>20009.88). Production percentages of infectious, domestic type, chemical and pharmaceutical and toxic wastes were 51.93, 38.16, 9.47, 0.44 respectively. Main components of produced dental waste were 14 components that consist of more than 80 percents of total dental solid waste. So, waste reduction, separation and recycling plans in the offices must be concentrated on these main components. "nConclusion: In order to dental waste proper management, it is suggested that in addition to educate dentists for waste reduction, separation and recycling in the offices, each section of dental waste(toxic,chemical and pharmaceutical, infectious and domestic type wastes) separately and according to related criteria should be managed.

Three cancerostatic platinum compounds (CPCs) including cisplatin, carboplatin and oxaliplatin are complexes of Pt and classified as probable carcinogenic compounds to humans. This study aimed to perform health risk assessment of platinum cytotoxic drugs for drinking water by developing a sensitive analytical method in the water resource of Qom Province in the central part of Iran. Concentrations of the platinum drugs were determined, including 052 ± 0.2 µg/L for cisplatin, 0.94 ± 0.36 µg/L for carboplatin and 0.27 ± 0.16 µg/L for oxaliplatin in influent samples, and 0.24 ± 0.07 µg/L for cisplatin, 0.28 ± 0.05 µg/L for carboplatin and 0.11 ± 0.01 µg/L for oxaliplatin in effluent samples. The results indicated that in all the well water samples related to the groundwater, the concentration of the platinum-based compounds was lower than the calculated limits of quantification (LOQ); the concentration of cisplatin, carboplatin and oxaliplatin across the samples in the station of drinking water distribution was also below the limits of detection (LOD). The resulting margin of exposure (MOE) is lower than one (MOE < 1) for the three groups including children, pregnant women and lactation women related to cisplatin and carboplatin was determined through exposure to raw and untreated drinking water. Further research is recommended to be conducted in this area, particularly environmental fate of metabolites and transformation products. [ABSTRACT FROM AUTHOR]

Background and Objective: Hexavalent chromium (Cr (VI)) is a highly toxic pollutant that isknown as a carcinogen and mutagen agent to humans. Photocatalytic reduction is one of the known ways to remove these contaminants. Therefore, the aim of this study was to investigate the catalytic effect of green iron nanoparticles, as eco-friendly materials, on photocatalytic reduction of Cr (VI) from wastewater. Materials and Methods: This is a laboratory study that has been done using a batch reactor with a 400 ml useful volume and medium pressure UVC lamp. Iron nanoparticles were synthesized using barberry leaf extract and iron chloride, then their performanceswere investigated in photocatalytic reduction process of hexavalent chromium. In this study the effect of different parameters such as pH (2-10), catalyst dosage (0-0.375g/l), reaction time (2-15min),and initial Cr (VI) concentration (10-200 mg/l) were investigated. The size of the green iron nanoparticles were determined by Transmission Electron Microscope (TEM) analysis. Data Analysis was performed by Excel software. Results: TEM analysis showed that the production of green nanoparticles of iron has been successful and their size was from 20 to 40 nm. The optimum pH equaled 2. The best conditions for the process obtained in initial chromium concentration of 50 mg/l, catalyst dose of 0.375 g/l, and contact time of 15 minutes and removal efficiency of 100% was reported in this condition. Photocatalytic reaction kinetics followed the second order kinetic equation. Conclusion: The results showed that green iron nanoparticles are efficient catalysts in the process of photocatalytic reduction of Cr (VI) from Synthetic wastewater. [ABSTRACT FROM AUTHOR]

Background and Objective: Perchloroethylene (PCE) is a chlorinated hydrocarbon used as a solvent in many industrial processes. In contaminated water and soil a great deal of PCE is found. This study aimed to determine the rate of decomposition of PCE occurred after advanced oxidation. Material and Methods: In this descriptive-analytic study conducted (2011) in public health faculty of Tehran University of medical sciences, gas chromatographic was used to measure PCE and gas chromatography - mass spectrometry for intermediate products. Chemical oxidation involves ultrasonic waves, ultraviolet light and hydrogen peroxide. Results: PCE was effectively decomposed by advanced oxidation processes. In these processes, the reaction rate was based on the equation of the first order and the rate of decomposition was proportional to the concentration. The higher was hydrogen peroxide, the more was decomposition, and the removal rate was higher at acidic PH. The intermediate products formed in the oxidation process were trichlorethylene, dihlorethylene, trichloroacetic acid, dichloroacetic acid and chloroacetic acid. Conclusion: The toxicity of intermediate products formed by degradation of Perchloroethylene compared to its initial toxicity is low. But it is a necessity to elongate the processes for having complete destruction of intermediate compounds and preventing from their adverse effects on the environment and human health. [ABSTRACT FROM AUTHOR]

Background and aims: This is a descriptive and cross sectional study. The aim of this study was to investigate the environmental ranking of industries located at west of Tehran based on the quantitative and qualitative characteristics of industrial wastewaters in 2011. Methods: This study was conducted by site visit, questionnaire completion, database production and results analysis. The questionnaire was consisted of 30 questions about quantity, quality and management of industrial wastewater. Total number of industries with over than 50 personnel, was 287. Class-weighted sampling was used and the sample size was contained 50 industries. In this study, industries were scored from 1 to 10, based on the flow rate, BOD and COD, generation of wastewater per worker per day and then were ranked according to the total score. Results: The average flow of wastewater generated by these 50 industries was 9422 m3/day. Wood and cellulose industries with 730 liters wastewater per worker per day was considered as the greatest wastewater generator. Minimum organic loading was related to non-metallic mineral industries with COD of 205 mg/ L and BOD of 85 mg / L. The maximum COD was related to paper industries with the rate of 8800 mg/ L and maximum BOD was related to food and drug industries with the rate of 1536 mg/ L. Conclusion: This environmental ranking was indicated that while paper industries contributed the most pollution load, non-metallic mineral industries had the least pollution load. [ABSTRACT FROM AUTHOR]

The wide use of subway system by citizens underlines the importance of hygienic issues including indoor air pollution in these public places especially in metro stations. The aim of this study was to investigate the bacterial contamination in indoor and outdoor air of two metro stations (Imam Khomeini and Sadeghiyeh stations) in Tehran subway system. In this cross sectional study, three sampling locations were selected in each station. Also, sampling was conducted in indoor air of two types (old and new) of trains. The range of bacterial colony count was 35-1501 CFU/m³. Maximum and minimum bacterial contamination levels in Imam Khomeini and Sadeghiyeh platform stations were averagely 1073 CFU/m³ and 242 CFU/m³, respectively. 14 bacterial species and genera were isolated; among them the dominant species were Staphylococcus epidermidis, Micrococcus luteus and Bacillus spp. Results showed that bacterial concentrations in indoor air were higher than the outdoor air; also the bacterial counts correlated significantly with number of the passengers (p<0.001) and air temperature (p<0.001). [ABSTRACT FROM AUTHOR]

The possibility of linear alkyl benzene solfunate (LAS) photocatalytic degradation through application of TiO2 nanoparticles was investigated. 10(mg/L) of LAS has been affected by either UV or TiO2 and simultaneous use of both of them in separated experiments. Moreover, the effect of initial concentrations of LAS and TiO2, pH, present various anions and different UV power was studied to determine the optimal operating conditions for LAS degradation in water. The amount of mineralization of LAS was reported by measuring the primary and final COD of the solution that was irradiated under optimized conditions. Maximum degradation was obtained at acidic pH, 50 mg/L of TiO2 and 30 minute irradiatign, time. It was also shown that 99.5% of LAS was degraded in optimal conditions. Kinetic analysis indicated that photo catalytic degradation rates of LAS can be approximated by pseudo-first order model. Measuring the initial and final COD of illuminated solution under optimized conditions, indicated that almost complete mineralization of LAS was occurred. Based on the results, UV/TiO2 process may be effectively applied in LAS removal in low concentrations but this process is not economically efficient in high concentrations. [ABSTRACT FROM AUTHOR]

Background and Aim: The association between particulate matter (PM) and cardiovascular diseases (CVD) was shown in the mid-1990's through several epidemiological studies. Increased hospital admissions of patients with cardiovascular and respiratory problems in days when, due to high concentrations of PM, air pollution is high, bears witness to this. In this study we measured concentrations of the PM fractions in the air in the central part of Tehran city, Tehran, Iran Methods and Materials: The concentrations of suspended particles (PM10, PM2.5 and PM1) were measured during February-June 2007 in two stations in central Tehran. Stations1 was in the Enghelab Square, a crowded part of the city with highly polluted air, where many educational institutes (e.g. Tehran University) are located, while station 2 was located near the Nasr Bridge, through which one of the most important highways (Martyr Chamran Highway) passes. The MP concentrations were measured once every 3 days, twice each day, once during the morning traffic rush hour (9-11 AM) and once during the afternoon traffic rush hour (4-6 PM), using a portable device, e.g., Environmental Dust Monitor Model GRIMM107. Results: One-way ANOVA tests showed significant differences (p<0.05) between PM concentration in the two stations. The daily mean concentrations of PM10, PM2.5 and PM1 were, respectively, 77.67, 44.46 and 26.89 μmm-3, in station 1, and 55.31, 28.15 and 19.12 μmm-3, in station 2. Conclusion: The concentrations of PM10, PM2.5 and PM1 were lower in both stations than the respective USEPA 24-hour primary NAAQS standards, established in 1987 for PM10 and in 1999 for PM2.5. However, the proportions of the total samples with PM concentrations exceeding the new EPA standards established in 2006 were 67% and 25% in stations 1 and 2, respectively. The air quality index (AQI) was unhealthy in 32% and 10.5% of the samples in stations 1 and 2, respectively. In addition, PM2.5 was the indicator pollutant in 87% of the samples in station 1 and 82% of the samples in station 2. [ABSTRACT FROM AUTHOR]

Arak waste stabilization pond facilities consist of two stabilization pond systems, module 1 and module 2. The existing facilities have had several problems in their operation. The objectives of this research were to evaluate the performance of stabilization ponds in wastewater treatment of the city of Arak, because of several problems in their operation, and to prepare a scheme of its upgrading, if necessary. Within the period of May to September 2007, analyses were carried out for both raw and treated wastewaters. Results of these investigations showed that the average effluent concentrations of BOD5, COD and SS taken from primary and secondary facultative ponds of module 1 were 91.5, 169, 114; and 70, 160, 123 mg/L, respectively. These results indicated that the effluent of the primary facultative ponds of module 1 were complied with the Iranian treated wastewater standards for agricultural reuse in terms of BOD5 and COD concentrations; hence the secondary facultative ponds could be changed to other primary facultative ponds in order to increase the capacity of wastewater treatment plant. For module 2, BOD5, COD, and SS average concentrations of treated wastewater for the secondary and tertiary facultative ponds were obtained as 69, 101, 77; and 76, 127, 78 mg/L, respectively. Thus the effluent of the secondary facultative pond was complied with the considered standards in terms of all studied parameters. Consequently, the tertiary facultative pond could be changed to other secondary facultative pond to upgrade both the quality and the quantity of treated wastewater. [ABSTRACT FROM AUTHOR]

In this research the application of Nanosil containing hydrogen peroxide and silver was studied in disinfecting swimming pool water and it's Environment. The effect of the disinfectant on Candida albicans (ATCC No. 10231), Aspergillus niger (ATCC No. 16404), Pseudomonas aeruginosa (ATCC No. 9027), Serratia marcescens (PTCC No. 1111), Klebsiella pneumoniae (ATCC No. 10031) and Staphylococcus aureus (ATCC No. 29737) ) was evaluated. The main objective of this experiment was to determine the effective dose of Nanosil which could be used for disinfecting the environment of swimming pools and other surface area. Then, the effectiveness of Nanosil was studied in two private and one public swimming pools. Heterotrophic plate count, thermotolerant coliforms, Pseudomonas aeruginosa and Staphylococcus aureus were monitored as the target microorganisms in disinfection practice According to the result of this study, it is recommended to apply the Nanosil with the concentration of >3% (30000 mg/L) for contact time of 30 min or more for practical disinfection in swimming pools environment. The application of Nanosil in real conditions of two private and one public swimming pools indicated that the acceptable microbial quality is also achievable if the disinfectant residual concentration would be as high as 20 mg/L in swimming pool water. [ABSTRACT FROM AUTHOR]

Atmospheric particulate matter may exert serious health hazards because of its chemical characteristics. The main objective of this study is to assess the concentrations of total suspended particles (TSP), particulate matter (PM) with an aerodynamic diameter ≤10 μm (PM10), and air-transmitted particulate trace metals in Tehran University (a central location in Tehran, capital of Iran) ambient air, for the period of 5 months viz. February–June 2007. Furthermore, the present work examines the daily levels of fine particles in comparison with the proposed limiting values from the U.S. Environmental Protection Agency (65 μg m−3 for PM10). The sampling for TSP and PM10 was performed using a high-volume sampler. The TSP and PM10 levels were determined by gravimetry and the metals by flame atomic absorption spectrometry. Arithmetic means of 151 ± 44 µg m−3 and 90 ± 38 µg m−3 were determined for TSP and PM10, respectively. Comparing with EPA primary and secondary air quality standards, only PM10 concentrations in 3 days were higher than the standard values. Heavy metal content of both TSP and PM10, such as chromium (Cr), cadmium (Cd), and lead (Pb), were also analyzed separately during the same period using atomic absorption spectrometry. The average concentrations of heavy metal in TSP were Pb: 183.63 ± 147.81 ng m−3; Cr: 13.72 ± 2.40 ng m−3; and Cd: 6.80 ± 1.97 ng m−3 and for PM10 were: 150.36 ± 157.01 ng m−3; Cr: 9.12 ± 2.14 ng m−3 and Cd: 6.87 ± 2.22 ng m−3. [ABSTRACT FROM AUTHOR]

Background and Aim: Methyl tertiary butyl ether (MTBE) is an oxygenated additive chemical added to gasoline, which is as a substitute for tetra ethyl lead, to reduce discharge of pollutants from automobile exhausts. This organic chemical is present in water samples collected from areas where gasoline wastes are abundant. The objective of this study was to investigate the possibility of MTBE removal from drinking water at the point of use (POU) by using an Iranian granulated active carbon (GAC) bed. Materials and Methods: Adsorption of MTBE from drinking water at POU was studied by using an Iranian GAC bed. The water samples treated by this filter adsorber were prepared synthetically at two concentrations (50 ppb and 100 ppb). In addition, the effects of residual chlorine at concentrations of 0.2 and 0.5 mg/L and of chloroform at a concentration of 100 ppb on removal of MTBE were determined. Results: It was found that this filter adsorber could treat 375 liters of water containing 50 ppb MTBE, 100 ppb chloroform and 0.2 ppm residual chorine. If the residual chlorine content was increased to 0.5 ppb, the volume of water treated would be 335 liters. The filter could t eat 195 liters of water containing 100 ppb MTBE, 100 ppb chloroform and 0.2 ppm residual chlorine to acceptable levels for drinking, provided the amount of MTBE is below the respective standard. Conclusion: Both residual chlorine and chloroform reduced the MTBE adsorption capacity on GAC due to occupation of adsorption sites. In addition, to the tendency of GAC to adsorb chloroform and chlorine was greater than that of MTBE. [ABSTRACT FROM AUTHOR]

Background and Aim: The scattered state of the rural populations- in terms of both the distance between villages and the distance between residential units within a single village- has made the task of supply, distribution and monitoring the quality of water a difficult one. In this study we looked at the bacteriological quality as well as access to safe potable water in selected villages of Tehran Province. This research started in February 2006 and ended in July the same year. Materials and Methods: In this cross-sectional field study, sampling points were specified on the basis of the populations of the villages served by the Tehran Rural Water and Wastewater Company. After systematic sampling, the specimens were transferred to the laboratory for testing. Data were analyzed using the SPSS and Microsoft Excel software packages. Results: Drinking water contamination with E. coli was observed in 5.99% of the villages. The degree of contamination was highest in the districts of Pakdasht, Savojblagh and Damavand, with rates of 33.34, 13.69 and 13.32 percent respectively. For 99.36% of the Tehran rural population the turbidity was lower than the standard value of 1053 set by the Iranian Institute of Standards and Industrial Research. Values in Savojblagh and Varamin were relatively higher, with rates of 96.51% and 99.30% respectively. Given the standard value of 1053, the residual chlorine levels were unacceptably low for 92.39% of the rural residents, with figures in the districts of Pakdasht, Damavand and Robatkarim reaching 75.67, 85.45 and 83.98 percent respectively. Conclusion: Based on WHO guidelines concerning the microbial quality of water published in 2006, the average indicator for lack of E.coli in rural water of Tehran was 94.01%, i.e. at an excellent level. Levels were good for Damavand and Savojblagh, low in Pakdasht and excellent in all other districts. [ABSTRACT FROM AUTHOR]