فهرست مطالب

Environmental Health Science and Engineering - Volume:4 Issue:3, 2007
  • Volume:4 Issue:3, 2007
  • تاریخ انتشار: 1386/04/10
  • تعداد عناوین: 10
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  • R. P. Tiwari, P. Bala Ramudu, R. K. Srivastava, M. K. Gupta Pages 139-146
    The sorption of metallic zinc from the pH-adjusted aqueous solution at varying initial concentrations onto a clay soil through batch equilibrium experiments has been studied. The pH of the initial concentrations ranging between 50 mg/L to 250 mg/L has been varied from 3 to 7. The sorption data fitted very well with both Langmuir and Freundlich isotherm models and Freundlich model gave higher correlation coefficients. The maximum sorption of metallic zinc occurred at pH=6. The pseudo-second order kinetics model was most agreeable with the experimental sorption data, whereas the pseudo-first order model was found to be insufficient. A nonionic surfactant was tested for its desorption potential and was found to be fairly effective at 2% concentration with removal of more than 60% sorbed Zinc.
    Keywords: Sorption, isotherms, desorption, zinc
  • K. Parthasarathi Pages 147-156
    Moisture play a crucial role in vermicomposting of pressmud (filter cake) (P). Five levels of moisture contents of pressmud (55-57%, 60-62%, 65-67%, 70-72% and 75-77%) at 31±2°C on earthworm activities (growth, reproduction and recovery rate of vermicompost) of Perionyx excavatus (Perrier)-an indigenous species and total microbial population, activity and nitrogen, phosphorous, potassium contents in the P vermicompost, over 60 days at an interval of 15, 30, 45 and 60 days have been studied. More and better worm biomass, cocoon production, hatchling number and rate of compost recovery were found in the 65-67% moisture. Besides this level, 70-72% and 60-62% moisture were adequate. On the other hand, 55-57% and 75-77% moisture did not have the desired effects on the growth and reproduction of earthworms and on vermicompost production. Enhanced microbial population and activity and nitrogen, phosphorous, potassium contents were found in fresh vermicomposts from 65-67% moisture than other moisture levels due to the ideal moisture of P for better multiplication of microbial population while passing through the worm gut with more activity, thereby enhancing the mineralization process resulting enhancement of nitrogen, phosphorous, potassium contents, whereas these decreased with decline in moisture content, immobilization and inactivation of microorganisms and/or increase in time (aging).
    Keywords: Moisture content, pressmud, Perionyx excavatus, reproduction, vermicomposts, microbial activity, nutrient contents
  • M. Ghorbanli, Z. Bakand, G. Bakhshi khaniki, S. Bakand Pages 157-162
    The air pollution effects on the activity of antioxidant enzymes were investigated on Nerium oleander and Robinia pseudo acacia in Tehran. Considering the information obtained from the Department of the Environment of Iran, Sorkh Hesar Park as well as South Azadi were selected as two sampling sites representing the unpolluted and polluted area respectively. A number of plant leave samples were collected from both sampling sites simultaneously. The activity of plant enzymes including peroxidase, catalase and ascorbate peroxidase was investigated using spectrophotometric methods. A higher level of peroxidase and catalase enzymes were measured in both plant samples collected from polluted area. However, this higher level was only statistically significant for the activity of peroxidase enzyme in Robinia pseudo acacia plants compare of to the control group (p < 0.05). The lower level of ascorbate peroxidase was observed in Nerium oleander plant leaves collected from the contaminated sampling site (p < 0.05), but though, the activity of this enzyme in Robinia pseudo acacia did not change significantly. The overall plant injury symptoms found in this study demonstrated that both Nerium oleander and Robinia pseudo acacia have a potential to be considered as effective bioindicators to reflect the environmental air quality in polluted areas.
    Keywords: Air pollution, antioxidant enzymes, Nerium oleander, Robinia pseudo acacia
  • A. Khanafari, H. Soudi, M. Miraboulfathi Pages 163-168
    The potent mycotoxin aflatoxin B1 is a secondary metabolite of Aspergillus fungi that grow, on a variety of food and feed commodities at any stage during growth, harvest, storage and transportation. The occurrence of aflatoxin contamination is global, with severe problems especially prevalent in developing countries. In present study, corn samples were contaminated with aflatoxin B1 in the concentration of 240 µg/kg. Four trials were inoculated by Lactobacillus plantarum (PTCC 1058). Three control assays were analysed in the same conditions. All the assays were kneaded and incubated for 4-7 days at 37°C. Aflatoxin B1 was determined after extraction by HPLC. Results showed a drastic removal of the mycotoxin with a reduction of 77 % for Aflatoxin B1 by Lactobacillus plantarum. In the Inoculated corns, spore germination of A. flavus was totally inhibited. Results in inoculated spikes showed a high percentage of reduction of aflatoxin after incubation by Lb. plantarum. Gram staining of a sample from inoculated corns and microscopic observation demonstrated that the growth of A. flavus spores was totally inhibited by Lb. plantarum. Fungal spores were surrounded by Lactobacillus plantarum and spores were degraded.
    Keywords: Biocontrol, Aflatoxin B1, Lactobacillus plantarum, corn, Aspergillus flavus
  • R. Salmasi, F. Salmasi Pages 169-172
    Soil adsorbing properties reduce sorption ability of the metal, which in turn may influence decision for remediation at contaminated sites. The objective of this study is presentation of a model based on soil properties to estimate the sorption of Cr(III) in chromium contaminated soils. Twenty uncontaminated soil samples, with properties similar to the contaminated soils were selected from around of city of Tabriz and treated with Cr as CrCl3. A multiple regression analysis with statgraph software was used to drive an expression that related Cr sorption to common soil properties. The results showed that four soil properties were important in determining the amount of Cr adsorbed by the soils including pH, cation exchange capacity, total inorganic carbon and clay content with nearly 80% variability in Cr sorption and a reasonable level of confidence by this model. The obtained model suggested that Cr(III) sorption was enhanced by higher soil pH, more total inorganic carbon, more clay, and higher cation exchange capacity.
    Keywords: Chromium, soil properties, sorption model, contaminated soil
  • A. A. Hanafi, Bojd, M. Shahi, M. Baghaii, M. Shayeghi, N. Razmand, A. Pakari Pages 173-176
    Rodents are one of the main health problems in the cities, especially in coastal area. These animals make economic damages and are potential health dangers in Bandar Abbas, the main economic southern port of Iran. In this study, rodents were captured from different parts of the city, before and after a control program during 2003-2004, transferred to the laboratory, identified and examined for ecto-parasites. Totally 105 rodents demonstrating four species: Rattus rattus (3%), R. norvegicus (78%), Mus musculus (3%) and Tatera indica (16%), were captured before the control program. The most frequency was observed in Ayatollah Ghafari quarter, 10 rodents per 24 traps. After 12 months, the duration of control program, rodents were re-captured to assessment the success of control activity. In this stage 35 small mammals demonstrated four species were obtained: R.norvegicus (51.4%), R.rattus (37.1%), T.indica (8.6%) and one weasel (2.9%). We found the most frequency in Khoon-sorkh quarter with 6 rodents per 24 traps. The identified ectoparasites were Xenopsylla buxtoni, Rhipicephalus sp., Polyplax gerbilli, Haplopleura captiosa, Ornithonyssus bacoti, Laelaps nuttalli, Dermanyssus americanus, Dermanyssus sanguineus, Haemolaelaps glasgowi and Echinolaelaps echidninus. The number of rodents reduced to one third after control program, shows the relative success of this program (p<0.05).
    Keywords: Rodents, control, ecto, parasites
  • A. Torabian, G. R. Nabi Bihdendi, P. Zanganeh Ranjbar, N. Razmkhah Pages 177-180
    Nanofiltration, widely developed over the past decade, is a promising technology for the treatment of organic and inorganic pollutants in surface and groundwater resources. The aim of the present research was to study the efficiency of textile dyes removal by a commercial nanofilter NF90 (Dow-Film Tec). Dye rejection was studied using basic dye (Basic Chrysoidine Cryst Yellow Gold 0.4%) with its relevant additive. Experiments were continued until the fouling time of the membrane. Each experiment was repeated after washing to evaluate the efficiency of the washing process. Results showed that the values of color removal were 97.98 % for the simulated textile wastewater containing basic dye. The membrane was sensitive to fouling since most of dyes were used for polyamide textile dyeing. Washing the membrane with a solution including NaOH (pH=12) and HCl (pH=2) showed its efficiency to solve the fouling problem. The filtration process was efficient and promising for reusing wastewater in this industry.
    Keywords: Textile industry, basic dye, dye removal, nanofiltration, water quality
  • J. B. Alam, R. K. Chowdhury, Z. Uddin Ahmed, A. S. M. Amin, A. K. M. H. B. Chawdhury Pages 181-190
    Existing solid waste management system of Habibganj municipality (pourashava) of Bangladesh was studied. A total of 234 households were surveyed. Solid waste generation rate was found to be 0.36 kg/cap/day. Household waste disposal was one of the main problems across the city. Among the different options of waste disposal, 21.4% and 23.9% respondents generally threw their wastes into nearby ponds and drains, respectively. About 14.5% of the sampled households discarded their wastes in their respective compound and only 12% households used bins supplied by the municipality. About 10.7% households disposed their garbage on the roadside. Lack of awareness, lack of dustbins, and improper maintenance of drainage system and lack of drainage facilities were the main reasons of the current inadequacy of the management system as reported by 183 (78%) respondents. The result indicate that for a 200 MT capacity composting plant, safe distance will be about 800 m from the disposal site in terms of odorous impact, while 500 m for health impact. In this study, a sustainable management system of solid waste disposal is suggested for the Habibganj municipal area.
    Keywords: Habiganj pourashava, solid waste, sustainable development, biogas, drainage problems, health impact
  • A. H. Mahvi, R. Nabizadeh, F. Gholami, A. Khairi Pages 191-196
    The Cr (VI) adsorption characteristics of platanus orientalis leaves and their ash were examined as a function of contact time, initial pH and metal ion concentration. Batch adsorption experiments were performed. The effects of Ca2, Mg2, Na and K on adsorption were studied. The effect of this adsorbent on COD in wastewater showed that 2g/L of adsorbent caused increase of 110mg/L and 76mg/L COD in deionized water in 120 minutes for platanus orientalis leaves and their ash , respectively. The maximum removal took place in the pH range of 6-7, contact time of 60 minutes and initial concentration of 2mg/L. Studies showed that the Freundlich adsorption model better fitted with the results than Langmuir with R2 > 0.85. The study showed platanus orientalis leaves ash was more favorable than living ones as well as in removing chromium from the aqueous solution.
    Keywords: Cadmium removal, Platanus orientalis leaves, ash, aqueous solution
  • K. Naddafi, J. Nouri, R. Nabizadeh, N. Shahbod Pages 197-201
    This paper studies the various resources (water, energy, paper) as well as other wastes consumption management at the National Library of Iran in Tehran. After setting the targets and specifying the correct management framework of resources consumption through the green management schedule, the resources analysis in consumption pattern in National Library of Iran was set up. Some attempt plans were performed to find out management solutions to the related issues. For the achievement of this aim, the first step was considered the study of general conditions of the Library through several visits, completing the checklists and questionnaires and then gathering the necessary information and analyzing them. The results of the fuel consumption in transportations related to the National Library showed that the major pollutants produced by the transportation were CO2, CO, NOx, and hydrocarbons. The rate of CO2 had a maximum level of 904 Kg and CO was 6 Kg, NOx was 2 Kg and hydrocarbons were 0.58 Kg. Among the equipments, which use energy in the Library, refrigerators produce the levels of CO2, SO2 and NOx .The total level of CO2, SO2 and NOx produced by all the equipments were 1140.32 Kg, 3.9072 kg and 2.886 Kg respectively. The results of water investigations showed that the total water consumption was 45459 L/year and the greater part of it was related to irrigation of the garden in the courtyard which was equal to 32471 L/year. Regarding to the wastes, the results of 30 times sampling showed the highest level to be related to aluminum and paper and a computer analysis revealed these results in the rates of 19745 Kg/year of CO2, 77.54 Kg/year, SO2 57.4Kg/year NOx and particulate matter was 2.92 Kg/year. Following the investigations carried out in management, executive solutions were suggested which led to the conclusion that the Green Management System should be established at this organization which should result in optimum consumption of resources such as water, power and paper in the National Library of Iran with considerable cost reduction.
    Keywords: Green Management System, pollutant, waste management, optimum consumption, consumption management