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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]

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]

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]