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In this study, actual soil samples, taken from Kharg Island, Iran, with high levels of total petroleum hydrocarbons (TPHs) were bioremediated by a bacterial consortium. The strains were: Pseudomonas sp., Stenotrophomonas sp., Achromobacter sp., Brevibacillus sp. and Staphylococcus sp., which were isolated from two highly polluted sites: Kharg Island and Kermanshah Oil Refinery. The bacteria were identified and confirmed by biochemical tests and the PCR assay. In order to isolate the bacteria, the enrichment method, in which crude oil (2%) was utilized as the sole source of carbon and energy, was used. The results showed that the adapted bacterial consortium could degrade nearly 60% of the pollution. Also, it was found that after 100 days of bioremediation only Brevibacillus sp. could survive in the environment.

Over the last few decades, the evidence on the adverse effects on the health of air pollution has been raised. Mortality is the most important health effect of ambient air pollution. We studied the relation between mortality and criteria pollutant air in Tehran, one of the highly industrialized, densely populated area and most polluted cities of the reign, during 2005-2014. For this purpose, we applied the approach proposed by the World Health Organization using the AirQ 2.2.3 model. Hourly concentrations of pollutants were taken from the Tehran environmental protection agency and Air Quality Control Company. In this model, the attributable proportion of health outcome, the annual number of excess cases of mortality for all causes were estimated. According to results, the number of total mortality caused by exposure to O3, NO2, SO2, PM10, PM2.5 in the past decade was 8042, 15141, 8136, 17776 and 20015 cases, respectively. The number of cumulative total mortality was 53110 cases in ten years. Furthermore, the number of cumulative cardiovascular and respiratory mortality 33887 and 8168 cases was estimated in last decade. A large number of residents of Tehran have died as a result of exposure to air pollutants; therefore for control and management of air pollution, appropriate actions on health and the environment should be performed.

This study explored the best-operating conditions for a novel electrocoagulation (EC) reactor with the rotating anode for textile wastewater treatment. The influence of operating parameters like inter-electrode distance (IED), current density (CD), temperature, pH, operating time (RT), and rotation speed on the removal efficiency of the contaminant was studied. A comparative study was done using conventional model with static electrodes in two phases under same textile wastewater The findings revealed that the optimal conditions for textile wastewater treatment were attained at RT = 10 min, CD = 4 mA/cm2, rotation speed = 150 rpm, temperature = 25oC, IED = 1cm, and pH = 4.57. The removal efficiencies of colour, biological oxygen demand (BOD), turbidity, chemical oxygen demand (COD), and total suspended solid (TSS) were 98.50%, 95.55%, 96%, 98% and 97.10% within the first 10 min of the reaction. The results of the experiment reveal that the newly designed reactor incorporated with cathode rings and rotated anode impellers provide a superior treatment efficiency within a short reaction time. The novel EC reactor with a rotating anode significantly enhanced textile wastewater treatment compared to the conventional model. The values of adsorption and passivation resistance validated the pollutants removal rate.

Tannery industries provoke the conspicuous quantity of deleterious effluent which has to be treated prior to discharge into the environment. Pre-treatment of tannery wastewater with aluminium sulphate is well known over decades, but due to the corrosive nature of sulphate this pre-treated water causes several issues in the biological treatment system. To overcome this issue a study was performed to understand the coagulant activity of aluminium formate and aluminium sulphate. The effect of coagulant activity as a function of pH and coagulant dose of Aluminium formate was studied and found that it surpassed aluminium sulphate in terms of Cr(VI), sulphate and COD removal by 10%, 6% and 10% respectively, while turbidity removal for both coagulants was found approximately equal. Possible mechanistic approach to the coagulation property of aluminium formate and aluminium sulphate could be inter particle bridging and sweep coagulation respectively. Formate [HCOO-] can be utilized as a counter anion in the place of commonly used sulphate anions as it is biodegradable, non-toxic and corrosive free compound. Therefore, Aluminium formate can be a promising coagulant for the pre-treatment of tannery wastewater.