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Aims Municipal landfill leachate contains high concentrations of heavy metals, organics, ammonia. The efficeincy of electrochemically removal of heavy metals from landfill leachate was studied. Materials & Methods The leachate was obtained from Kahrizak landfill in south of Tehran. The experiments were carried out by batch process. The 2liter batch reactor was made of glass. There were eight anodes and cathodes electrodes. The electrodes were placed vertically parallel to each other and they were connected to a digital DC power supply. The pH and conductivity were adjusted to a desirable value using NaOH or H2SO4, and NaCl. All the runs were performed at constant temperature of 25°C. In each run, 1.5liter of the leachate was placed into the electrolytic cell. Samples were extracted every 10min and then filtered through a mixed cellulose acetate membrane (0.42μm). The amount of Lead, Zinc and Nickel removal was measured at pH=7 and in current density of 0.5, 0.75, and 1A. Findings When current density and time reaction increased, removal efficiency of heavy metals such as Lead, Zinc and Nickel increased. At initial pH=7, density 1A and reaction time= 60min, Lead, Nickel and Zinc were removed up to 86, 93 and 95%, respectively. Conclusion Electrochemical process can be proposed as a suitable technique to remove heavy metal from landfill leachate.

Aims Textile industries are among the manufactures which produce the highly polluted waste water. The purpose of this research was to evaluate the effect of vermifiltration on COD and color removal from textile waste water. Materials & Methods This experimental research was performed March to August 2014 in one of the textile factories of Kashan region, Iran. The glass cubic kits with- without Eisenia fetida were used to filter the waste water samples. Data was analyzed using Kruskal–Wallis and two-way analysis of variance in SPSS 19 statistical software. Findings The mean of COD concentration in the raw waste water samples was 1324.24±757.01mg/l which was decreased to 598.22±349.33 and 831.32±445.19mg/l after the experimental and control kits usage, respectively (p

Aims Heavy metals in the environment are toxic to plants, animals and human. This study aimed to investigate concentration of Arsenic, Lead and Cadmium in Iranian and non- Iranian rice which have been sold in Kashan City, Iran shops. Materials & Methods In this cross-sectional study, 126 samples from 42 trademarks (15 Iranian and 27 non-Iranian) rice were collected from Kashan shopping centers. At first each sample was ashed, and then they have been dissolved with nitric acid. Heavy metal concentration was evaluated by inductively coupled plasma emission spectrophotometer. Data were analyzed by SPSS 16 software using One-sample and Independent T-tests. Findings Arsenic was not found in any of rice samples. There was a significant difference between Pb concentration in both Iranian and non-Iranian rice samples. There was not a significance difference between Cd concentration in Iranian (p=0.823) and non-Iranian (p=0.346) rice samples according to Iran national standards but there was a significant difference between Cd concentration in both Iranian (p=0.001) and non-Iranian (p=0.001) rice samples according to WHO and FAO standards. Conclusion Consumed rice pollution with Pb is considerable but with Cd is low. Arsenic concentration in Iranian and non-Iranian rice is less than Iran national and WHO/FAO standards.

Aims Several methods have been used for textile wastewater treatment. The aim of this study was to evaluate the efficiency of Rosa damascena watering waste ash for COD and color removal from textile wastewater. Materials & Methods Rose watering waste was gathered from one of the Kashan processing plants. The raw wastewater sample was taken from one of the textile industries in Kashan countryside. All experiments were run in the fixed volume (1L) of textile wastewater, contact times (15, 30, 45, 60, 75, and 90min), pHs (3, 5, 7, and 9) and different doses of rose watering waste (500, 1000, 2000, and 4000mg) at the room temperature (25°C). Moreover, biosorption kinetic studies for COD were done using the pseudo first and pseudo second order models. Findings The amount of COD and color removal were increased by contact time increasing from 15 to 60min and the maximum removal of COD (50.3%) and color (31.4%) were seen at minute 60. Therefore, the contact time of 60min was chosen as the optimum contact time for the first step. The maximum amount of COD (51.9%) and color (32.9%) removal were seen at pH=5 and biosorbent dose of 2000mg. Changes at pH and biosorbent dose had significant effects (p