Iranian Journal of

Background and Objectives :Microorganisms including Fungi, are among air-transmitted infectious agents at hospitals and patient care settings, which in addition to patients, can afflict Health Care Workers (HCWs) and visitors, and may results in extravagant economic burden and impact on human health. Use of nanotechnology and especially nanosilver particles is one of the methods which are used in infection control. This article is the result of a research project investigating nanosilver painting effect on bioburden of indoor hospital air.
Materials and Methods: The study was aimed to assess antifungal effects of nanosilver painting. Three rooms were selected at the infectious diseases ward of Imam Khomeini hospital complex. Two of the rooms were painted with two brands of nanosilver paints provided from two separate companies (as cases), and the third room with non-nanosilver paint brand(as control).
Results: Air sampling was carried out using a portable air pump (Quick Take 30) at pre-planned schedule Each Sampling was done in two minutes with the rate of 28.3 Liter per minute. Samples were transferred on Sabourauds Dextrose Agar culture, to count the colonies of fungal based on Colony Forming Unite (CFU/m3). Results were analyzed by ANOVA method.
Conclusion: Active sampling method was not able to show statistically significant reduction in the total fungal bioburden between the control and case rooms. In evaluating the time trend of the nanosilver paints effect, sampling measures revealed that nanosilver paints had statistically significant effect in fungal bioburden reduction in the first third( i.e. first month) of the study period.

Background and Objectives: Microbial fuel cells are the electrochemical exchangers that convert the microbial reduced power, generated via the metabolism of organic substrate, to electrical energy. The aim of this study is to find out the rate of produced electricity and also treatment rate of simulated wastewater of food industries using dual chamber microbial fuel cell (MFC) without mediator and catalyst.
Materials and Methods: MFC used in this study was consisted of two compartments including anaerobic anode chamber containing simulated food industries wastewater as synthetic substrate and aerobic cathode chamber containing phosphate buffer, respectively. These two chambers were separated by proton exchange membrane made of Nafion. Produced voltage and current intensity were measured using a digital ohm meter and the amount of electricity was calculated by Ohm's law. Effluent from the anode compartment was tested for COD, BOD5, NH3, P, TSS, VSS, SO42- and alkalinity  in accordance with the Standard Methods. 
Results: In this study, maximum current intensity and power production at anode surface in the OLR of 0.79 Kg/m3.d were measured as 1.71 mA and 140 mW/m2, respectively. The maximum voltage of 0.422 V was obtained in the OLR of 0.36 Kg/m3.d. The greatest columbic efficiency of the system was 15% in the OLR of 0.18 Kg/m3.d. Maximum removal efficiency of COD, BOD5, NH3, P, TSS, VSS, SO42- and alkalinity, were obtained 78, 72, 66, 7, 56, 49, 26 and 40%, respectively.
Conclusion: The findings showed that the MFC can be used as a new technology to produce electricity from renewable organic materials and for  the treatment of different municipal and industrial wastewaters such as food industries.

Background and Objective: Phenol presence in water and wastewater is interesting because of its stability in environment and health problems. Therefore, it must be removed for water pollution prevention. The aim of this study was to evaluate phenol adsorption from aqueous solutions using walnut green hull. Materials and Methods: This was an experimental study in which walnut green hull was used as biosorbent with a range of mesh 40. In this study, stock solution of phenol was prepared and effects of effective parameters such as pH (4,6,8, and10), contact time (3-60 min), adsorbent dosage (0.25-5 g/L), and initial phenol concentration (10,20,40, and 50 mg/L) on adsorption process were evaluated. Moreover results were evaluated using Langmuir and Freundlich isotherms and first order and pseudo-second order kinetics. All experiments were conducted in double and the mean adsorption rate was reported. Results: The maximum adsorption capacity of 30.30 mg/g corresponded with Langmuir model. Kinetic evaluation indicated that the adsorption of phenol by the walnut green hull clearly followed the pseudo-second order reaction. It was found that increasing contact time and adsorbent dosage would lead to increasing of adsorption of phenol and increasing pH and initial phenol concentration lead to decreasing of phenol adsorption. Maximum phenol removal was achieved at pH 4, with more than 99.9 % efficiency. Conclusion: The results of this study show that the walnut green hull can be used effectively in phenol removal, because walnut green hull is agriculture waste and is produced annual in high volume hence, it can be used as adsorbent in phenol removal from wastewater.

Background and Objectives: Perchlorate, as an emerging contaminant, has attracted notice of the most individuals and organizations. Presence of perchlorate in the human body can lead to inappropriate regulation of metabolism in adults. Moreover, due to inhibition of iodide uptake in the thyroid gland, it causes neurological and behavioral problems in infants and children. United States Environmental Protection Agency (EPA) has enacted 15 µg/L perchlorate in drinking water as a guideline value. Regarding the possible sources and potential presence of perchlorate in the environment of the study area, and the unique characteristics of this pollutant, such as extreme water solubility, high mobility in soils and stability in the environment, the status of its contamination was assessed in soil, surface water and drinking water in the study area (Khorramshahr County).

Materials and Methods:  Soil and water samples were taken during February to April, 2013. Combined sampling was used for soil sample collection and the random sampling was used for water (surface and drinking water) samples. Each sample was analyzed using ion chromatography. In this study, 15 samples of surface soil and 22 samples of surface and drink water were tested for perchlorate analysis.

Results: It was found that all surface soil and water samples collected from the study area were contaminated with perchlorate and exceed the standard level. Concentration of perchlorate in surface water and drinking water was 1400-5800 and 700-5900 µg/L respectively and in surface soils was 3.3-107.9 mg/kg.

Conclusion: The assessment of perchlorate in soil, surface water, and drinking water in the study area is extremely higher than recommended standards and therefore is a threat to the health of consumers.