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Introduction: The amount and composition of municipal solid waste, as basic data, require to design, operation and optimization of waste management systems. The aim of this study was to investigate the qualitative and quantitative of municipal solid waste in tabriz city. Materials and Methods: This is a cross-sectional study. The samples were collected from all regions (10 regions) of Tabriz city. The samples have chosen according random cluster sampling during a year. 12 samples were collected in each season. Then, the data were analyzed by SPSS and Excel softwares. Results: The results indicated that amount of MSW was 1200 tons per day. The content of organic material, paper & cardboard and recyclable (plastic, metal, glass and etc) was 52%, 13.15% and 19%, respectively. The maximum and minimum production rate was in august and January, respectively. Conclusion: Approximately, 85% of wastes included the recyclable and organic materials which the reuse of this material prevents the environmental pollution. The citizens believed that the most important of MSW program should be the promoting awareness, waste reduction and recycling.

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Background and purpose: Pphenol is one of major available compound in industrial wastewater. Phenol is classified as priority and dangerous pollutant in International Agency for Research on Cancer (IARC) and in list of EPA. Thus, the purpose of this study is survey on effect of sorbitol on phenol removal rate by lemna minor. Materials and methods: Tthis is an empirical- lab study. In this study, lemna minor in various amounts (0.3, 0.4, 0.6gr) was contacted with phenol concentration of 5, 10, 25, 50 ppm and sorbitol was added in known amounts into containers (0.2 and 1gr). In order to prevent of probable error, all experiments were done 2 times. Every 4 days, samples were provided from containers and the phenol concentration was determined by colorimetery in wavelength of 510nm.. Results: Tthe findings of this study showed that the increasing of initial concentration of phenol can decrease the removal rate and in concentration of less than 10 mg/l, the removal rate can be up to 95-99%. The removal rate of phenol increase by increasing of contact time and amount of lemna. Presence of sorbitol in culture medium can lead to increase of growth and reproduction and increasing of removal rate of phenol by lemna. Conclusion: Llemna minor is able to remove of phenol from aqueous. The addition of sorbitol carbohydrate can lead to increase of growth and reproduction and the efficiency of phenol removal by leman minor.

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Background and purpose: Fluoride in drinking water can be either beneficial or detrimental to health depending on its concentration. Its high concentrations leads to dental and skeletal fluorosis and lesions of the endocrine glands, thyroid and liver. This paper describes the removal of fluoride from water using lemna minor. Material and methods: This research was a lab study. The lemna minor plants were collected and dried in the oven at 105 in 24 h and sieved in 18-30 mesh. The optimum values of pH, contact time and adsorbent dosage were determined and the different concentrations of fluoride were experimented in lab scale conditions for modified lemna minor. The fluoride concentration was measured in wavelength of 518 nm by spectrophotometer. Also, the found data of this research were fitted with Variety Isotherm and kinetic models. Results: The results showed that by increasing pH solution, removal efficiency decreased and optimum pH was 5. Increasing of contact time and adsorbent dose can lead to the increase of the removal efficiency.Adsorption isotherm data show that the fluoride sorption followed the Langmuir No 2. Fluoride sorption is better agreed with pseudo- second order of Kinetics model which was well described by pseudo- second order model. Conclusion: The result of the present work shows that lemna minor can be used as an effective and cheap adsorbent for fluoride removal.

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Ramezan-Ali Dyanati-Tilaki¹,
Zabihollah Yousefi¹,
Jamshid Yazdani-Charati ²,
Davoud Belarak<sup>3

1</sup> Health Sciences Research Center, Department of Environmental Health Engineering, School of Health, Mazandaran University of Medical Sciences, Sari, Iran
² Health Sciences Research Center, Department of Biostatistics, Mazandaran University of Medical Sciences, Sari, Iran
³ Student Research Committee, School of Health, Mazandaran University of Medical Sciences, Sari, Iran




In the article published in volume 23, issue Suppl-2, 2013, the second author’s first name is Zabihollah Yousefi, and third author’s last name is Jamshid Yazdani-Charati, were incorrect which is now corrected.