Induction of lambda phage carring verotoxin1 gene from a verotoxigenic strains of Escherichia coli and released verotoxin1 were studied under environmental factors of shaking and termperature. Verotoxin1 phage in Escherichia coli PA 101 and transductants was confirmed by bacteriophage detection assay. Shaking of culture media and increasing temperature until 42°C increased phage particles in supernatants of Escherichia coli PA 101. Our results indicate that environmental factors such as shaking movements in natural inhabitates of bacteria such as river or sewage streams and temperature rise in summer season could be factors in induce and release free verotoxin1 – producing phage particles in nature that in turn could be the source of phage spreading to other related bacteria , and responsible for increased outbreaks of food borne diseases with verotoxigenic Escherichia coli in warm monthes of year in tropical areas.

Advanced compact wastewater treatment processes are being looked for by cities all over the world as effluent standards are becoming more stringent and land available for treatment plants more scarce. In this investigation, a new biofilm process for this purpose was studied. The design and operational criteria of a full scale extended aeration activated sludge system was compared with an H-IFAS reactor which has been operated at a pilot scale. The objective was to define the feasibility of using the H-IFAS (Hybrid Integrated Fixed Film Activated Sludge) reactor for upgrading the existing wastewater treatment plants with conventional processes. The results showed that besides the considerable difference between the organic loading of the two processes, H-IFAS reactor has a very good capability to reduce simultaneously the concentration of nitrogen and phosphorus. Organic degradation rate in extended aeration and H-IFAS systems were 0.3 and 6.22 kgCOD/m3.day at 23.48°C, respectively. Nitrification, denitrification and phosphorus removal rate for the H-IFAS reactor were 343.28 g N/m3.day, 338.17 gN/m3.day, and 204.78gPO4-P/m3.day, respectively. At the same conditions, these criteria for extended aeration activated sludge processes were obtained as 75gN/m3.day, 28.5 gN/m3.day and 7 gPO4-P/m3.day), respectively.

Conventional analytical method for organic pollutants in water requires extraction of the pollutants, using hazardous solvent. Solid phase microextraction is a solvent free equilibrium extraction method, in which, proper calibration can allow quantitative determinations of organic pollutants at a very good sensitivity without the use of any organic solvent. Because individual volatile organic carbons are generally exposed environmentally and present in urine only at trace levels, a sensitive and accurate determination technique is essential. So, this study describes the optimization of headspace solid phase microextraction (HS-SPME) followed by GC-FID for benzene in spiked urine. Through this investigations, the parameters affecting the extraction and gas chromatographic determination of analytes, including extraction time, temperature, desorption temperature, desorption time, salt addition, sample pH, sample volume and sample agitation were studied. An optimized headspace extraction was carried out at 30°C for 6 min in the presence of 0.2 g/mL of NaCl in the sample solution. Desorption of the analytes was carried out for 60 sec. at 250°C. The optimized procedure was also validated with three different pools of spiked urine samples and showed a good reproducibility over six consecutive days as well as six within-day experiments. The accuracy, linearity, detection limits were also determined. The headspace solid phase microextraction, GC-FID technique provides a relatively simple, convenient, practical procedure, which was here successfully applied to determine benzene in spiked urine.

Tabriz petrochemical complex is located in the northwest of Iran. Major products of this industry include raw plastics like, polyethylene, polystyrene, acrylonitrile, butadiene, styrene, etc. Sources of waste generation include service units, health and cure units, water, power, steam and industrial processes units. In this study, different types of solid waste including hazardous and non hazardous solid wastes were investigated separately. The aim of the study was to focus on the management of the industrial wastes in order to minimize the adverse environmental impacts. In the first stage, locating map and dispersion limits were prepared. Then, the types and amounts of industrial waste generated in were evaluated by an inventory and inspection. Wastes were classified according to Environmental Protection Agency and Basel Standards and subsequently hazards of different types were investigated. The waste management of TPC is quite complex because of the different types of waste and their pollution. In some cases recycling/reuse of waste is the best option, but treatment and disposal are also necessary tools. In this study, using different sources and references, generally petrochemical sources, various solid waste management practices were investigated and the best options were selected. Some wastes should be treated before land filling and some of them should be reused or recycled. In the case of solid waste optimization, source reduction ways were recommended as well as prior incineration system was modified.

Three strains of Azotobacter chroococcum were studied to produce poly-β hydroxybutyrate as a inclusion body by whey degradation. Optimum degradation whey results were obtained when using whey broth as a fermentation medium without extra salt, temperature at 35 °C and pH 7 (P<0.05). Lambda max for whey broth medium was determined probably about 400 nm. The effect of different nitrogenous rich compounds (NH4NO3, Bactopeptone, Casein, Yeast extract, Meat extract, Protease peptone and Tryptone) on whey degradation showed that incorporation of nitrogenous compounds into the medium did not increase whey degradation by Azotobacter chroococcum 1723 (P<0.05). But poly-βhydroxyl-butyrate production was increased in presence Meat extract up to 75% of the cell dry weight after 48h. The addition of nitrogenous sourced (except ammonium nitrate) had a positive effect on poly-β hydroxyl-butyrate production as it peaked in the presence of Meat extract and 4.43 g/L was accumulated in comparison to 0.5g at diazotrophically growing cells. Increasing the O2 values resulted by shaking at 122 rpm in decreased poly-β hydroxyl-butyrate yield form 4.43 to 0.04 g/L. The results show that this medium supports the growth of strain 1735 and also that this waste could be utilized as a carbon and nitrogen source. Production of poly-β hydroxyl-butyrate by using whey as a medium looks promising, since the use of inexpensive feed-stocks for poly-β hydroxyl-butyrate is essential if bioplastics are to become competitive products.

Tajan River is among significant rivers of Caspian Sea water basin. Pollution sources that threaten the quality of water in Tajan River may be classified in to two categories namely point and non-point sources. Major pollutants of latter category are Mazandaran wood and pulp, Paksar dairy products and Sari Antibiotic production factories, as well as 600-dastgah residential area. On the other hand, non-point sources whose waste is considered as a distributed load consist of Sari municipal wastewater and agriculture-related pollutants that are drained towards the river. In order to model the quality of river flow, Qual2E model is taken in to consideration. Considering TDS, the river quality is completely acceptable in cold seasons. However, in spring and summer the value of this parameter is increased and this causes some restrictions in the use of this water for irrigation of specific sensitive crops. Agricultural activities and consequent irrigated waters are the major causes of higher reported TDS values in warm seasons. Current status of DO is completely acceptable and this is highly related to the relative high value of width on depth ratio along the river. BOD and COD locate in a fairly poor condition. Quality deterioration is more noticeable in cold seasons. Higher rate of precipitation and consequent greater runoff generation towards the river basin justify the relative increase of mentioned parameters in fall and winter. Generally, non-point pollution sources are more contributed in deterioration of Tajan River water quality.

With regard to the relationship between exposure to electromagnetic fields and development of potential biological system impairments and increasing number of these fields, the current research was conducted in 2004 on 101 employees of high voltage centers to determine the role of working in these fields on mental health. One hundred and one employees were exposed to electromagnetic field at 50 Hz found from 230 kV current.We used SCL-90-R test and compared the subjects with the control group.Data analysis showed that the mean scores of the case group in Global Severity Index and Positive Symptom Total with significant difference were higher than that of the control group (P<0.022 and P<0.049). Positive Symptom Distress Index showed no significant difference between the two groups. Cases had also higher scores in all subscales in comparison with the control group. It was statistically significant for subscales of somatization, depression, anxiety, hostility and phobia. For psychoticism with P>0.05 it tended not to be significant. No correlation was found between age, marital status and split-shift working with GSI scores. Employment in electromagnetic fields at extremely low frequency can lead to the development of mental disorders. However, the results need confirmation by other controlled trials.

Malaysia and Thailand are tropical countries relatively rich in water resources, but both suffer numerous water problems, chief of which is excessive domestic wastage. A lop-sided approach focusing on water supply management and neglecting water demand management have caused water problems to escalate in both countries in recent decades due to population explosion, rapid urbanization, industrial expansion and climate change. As the total quantity of available water is finite but demand increasing at geometrical rates, Malaysia and Thailand are facing water problems which have severe impacts, particularly on women. This study compares the main water issues faced by two cities, Georgetown in Malaysia and Pattaya in Thailand, both medium sized and major tourist destinations. This paper compares various water indicators for both cities, water use characteristics of consumers, and consumers’ perception and willingness to pay. It also attempts to highlight the role of gender, documenting how women can manage water via water demand management in addressing water shortages. The paper concludes that water users need to be involved in a bottom-up approach in a sustained national water demand management initiative towards achieving sustainable management of water resources in both cities.

The sorption of dyes from aqueous solutions on to sludge-based activated carbon have been studied and compared with commercial activated carbon. Adsorption parameters for the Langmuir and Freundlich isotherms were determined and the effects of effluent pH, adsorbent dosage, contact time and initial dye concentration were studied. A pseudo-second order kinetic model has been proposed to correlate the experimental data.

Polycyclic Aromatic Hydrocarbons are ubiquitous in the urban atmosphere and one of the most atmospheric pollutants to be identified as suspected carcinogens .The objective of this study was to compare particulate PAH profiles from several sites across Tehran. Atmospheric concentrations of Polycyclic Aromatic Hydrocarbons in Tehran were evaluated to study particulate PAH profiles in different sites. The particles size distributions were unimodal with a fine mode diameter (PM<0.49 μm). Five sites were selected in residential areas and one site in rural area for representing various situations and role of motor vehicles in producing Polycyclic Aromatic Hydrocarbons. Organics on the filter were extracted with acetonitrile and a group of 16 Polycyclic Aromatic Hydrocarbons was selected for evaluation. PAH identification was done by High Performance Liquid Chromatography. Total PAH concentration associated with particles collected on the six-stage cascade impactor stages and after-filter in different sites ranged between 0.132 to 234.3 ng/m3. The mean concentrations of Polycyclic Aromatic Hydrocarbons, collected on each stage were: 4.17 ng/m3 for PM10-7.2 μm, 5.69 ng/m3 for PM7.2 - 3 μm, 11.95 ng/m3 for PM3 - 1.5 μm, 9.18 ng/m3 for PM1.5-0.95 μm, 2.82 ng/m3 for PM0.95-0.49 μm and 47.91 ng/m3 for PM < 0.49 μm respectively.