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Trend of Groundwater Quality Changes, Using Geo Statistics (Case Study: Ravar Plain)
2016
Babakhani, Maral | Zehtabian, Gholamreza | Keshtkar, Amir Reza | Khosravi, Hassan
Groundwater aquifers are an important source of water supply for agriculture, industry and drinking. The present study investigates the changes in the quality of groundwater using geostatistical methods in the Ravar plain during a 10-year period. In this study, after selecting the appropriate spatial interpolation method to draw water quality parameters such as TDS, SAR and EC, zoning maps of Ravar plain were provided for three periods of time: the first period (2002-2005), an intermediate period (2006-2009) and the final period (2010-2012) in two seasons using ArcGIS 10.1. For this purpose, data were evaluated in GS+ 5.1 software, after calculation, the best model with the lowest estimated error was selected for zoning water quality parameters. Because of the lowest estimation error, Kriging, Gaussian and Spherical variogram models were selected as appropriate interpolation method for zoning the quality parameters. The results of the spatial analysis of TDS showed that TDS have been increased in the study area. Due to the amount of dissolved solids, EC amount was highly variable. According to the Wilcox classification, at the end of the period, water quality of agricultural was inappropriate in most of the area which represents the increase of electrical conductivity during the period.
Show more [+] Less [-]Antibiotics Removal in Biological Sewage Treatment Plants
2016
Ghosh, Gopal | Hanamoto, S. | Yamashita, N. | Huang, X. | Tanaka, H.
This study investigated the occurrence and removal of 12 antibiotics (ciprofloxacin, enrofloxacin, levofloxacin, norfloxacin, nalidixic acid, azithromycin, clarithromycin, roxithromycin, lincomycin, novobiocin, sulfamethoxazole, trimethoprim) at four sewage treatment plants (STPs): two STPs in Kyoto, Japan and two STPs in Beijing, China. The STPs differed in design and operation conditions, utilized a variety of secondary treatment processes. The antibiotics were frequently detected in influents and effluents, and ranged from ng/L up to lower μg/L. In influent, clarithromycin (1.1–1.6 μg/L) and levofloxacin (3.6–6.8 μg/L) were detected in the highest concentration in Japanese and Chinese STPs, respectively. The overall elimination of the antibiotics were differed between STPs and ranged from negative to >90%. These data demonstrate that there are detectable levels of antibiotics are discharging from STPs, and only some of these antibiotics are being removed in a significant proportion by STPs. It was also observed that biological nutrient removal based sewage treatment processes (anaerobic–anoxic–oxic: A2O; and anoxic–oxic: AO) have relatively higher antibiotics removal efficiencies than oxidation ditch (OD) processes.
Show more [+] Less [-]Municipal Solid Waste Management using GIS Application in Mirpur Area of Dhaka City, Bangladesh
2016
Islam, S. M. | Rahman, Syed | Hassan, Mahmud | Azam, Gausul
Identifying Municipal Solid Waste (MSW) disposal sites and appropriately managing them is a challenging task to many developing countries like Bangladesh. It is a complex issue in an urban area, as increasing population levels, rapid economic growth and rise in community living standard, accelerates the generation rate of MSW. The study area is zone-2 (Mirpur-Pallabi) of Dhaka North City Corporation (DNCC) (10.40 km2) is a residential area, from where about 353.34 ton/day solid waste is generated and among them about 57.43% were managed by DNCC. There are 41 different size containers present at 17 locations in study area. The existing site and waste collecting containers are not sufficient, which deteriorates the environment due to illegal waste dumping and about 15 illegal dumping sites were identified. To identify proper waste dumping site and prevent contamination, Geographical Information System (GIS) was used to propose an efficient scenario with relocating the existing waste collecting containers and another scenario was proposed with number of containers (73) to attain an 93.68% waste collection efficiency including optimization and selection of waste collecting routes for the study area. This study also indicate that the application of GIS is an efficient and low cost tool to study and select appropriate dumping site so as to facilitate decision making processes.
Show more [+] Less [-]Assessment of Salinity Hazard of Irrigation Water Quality in Monsoon Season of Batiaghata Upazila, Khulna District, Bangladesh and adaptation strategies
2016
Shammi, Mashura | Karmakar, Bikash | Rahman, Md. | Islam, Md | Rahaman, Rashadur | Uddin, Khabir
Batiaghata Upazila, Khulna District in south-west coastal region of Bangladesh is the mostly saline affected area, where agriculture activities are mainly dependent on rainfall. 23 water samples from surface water and shallow tube well (STW) were collected in the monsoon season and analyzed for physico-chemical properties to classify them according to salinity hazard. Electrical Conductivity (EC) of both surface and groundwater samples were slightly higher than that of acceptable limit ( Ca2+ > Mg2+ > K+ in both surface and groundwater while the anions trend in both surface and groundwater of the study area were Cl¯ > SO42¯ > PO43¯. EC and TDS showed high positive correlation with Na+, K+ and Ca2+ with Cl¯ as confirmed from Correlation Matrix and Principal Component Analysis (PCA). Most of the STW water samples compared to the surface water had higher Soluble Sodium Percentage (SSP) values while Sodium Adsorption Ratio (SAR) indicated the surface water and ground water with low sodium hazard. The Kelly’s ratio of STW water is more subjected to sodium hazard compared to surface water in the study area.
Show more [+] Less [-]Photocatalytic Degradation of Benzene and Toluene in Aqueous Medium
2016
Singh, Pardeep | Borthakur, A. | Srivastava, N. | Singh, R. | Tiwary, D. | Mishra, P.K.
The resource intensive human activities (such as mining and extraction of mineral oils for betterment of life and modernization of society) have increased environmental pollution several folds. Products of mining and petrochemical industries are advantageous for the modern society. But waste generated such as BTEX from such industries are carcinogenic, toxic and causes adverse effects on environment and human health. These wastes are classified as hazardous waste which cannot be used further. Pollution of soil-water interface due to the release of hydrocarbons in environment is a major public health concern, and therefore, remediation of these pollutants is needed to reduce risk to human and environment. Various methods such as biological, chemical and physical method are used to degrade these pollutants from wastewater. In the present works photochemical degradation of toluene and benzene in wastewater are studied using activated Carbon−TiO2 composites as catalysts in the presence of UV irradiation in photochemical reactor. Composites are prepared by sol-gel method and further characterized by X-ray diffractometry (XRD), scanning electron microscope (SEM) and Fourier transformed-Infrared spectroscopy (FT-IR). The Photocatalytic efficiencies of the synthesized composites were determined by the mineralization of toluene and benzene under UV irradiation in photochemical reactor.
Show more [+] Less [-]Adsorption of arsenic on soil under different soil moisture conditions
2016
Sultana, Razia | Kobayashi, Katsuichiro
The adsorption study was conducted on three Japanese soils with different soil properties to characterize the adsorption pattern of Arsenic (As). Double tube method was used to find out the effect of soil moisture levels on As adsorption. For this study, besides double tube method, conventional batch method also was used. The As adsorption showed two phase kinetics. An initial and rapid adsorption was found at first hour and then gradually preceded before equilibrium in all the three soils in the case of double tube method and in clay loam and light clay soil in the case of batch method. Adsorption seemed to reach equilibrium at 24 h in both methods, though the initial adsorbate load was not the same at the same applied concentration in the methods. Adsorption activity differed according to soil and as well as to the methods. The highest adsorption was found in clay loam soil followed by light clay and sandy loam soil. The linear model of Freundlich adsorption was found better fitted in the case of double tube method than batch method. Suggesting that, under the experimental conditions stated here, the double tube method is more appropriate to describe the adsorption of As in the three Japanese soils under normal field condition. The concentration of As in soil water was slightly increased at different moisture levels from 50%-80% which may contribute significantly to the bioavailability of As at the moisture level below maximum filed capacity.
Show more [+] Less [-]Plant-Aid Remediation of Hydrocarbon-Contaminated Sites
2016
Daryabeigi Zand, Ali | Hoveidi, Hassan
Phytoremediation is an emerging green technology that uses plants and their associated microbes to remediate different environments contaminated with various pollutants. Phytoremediation, as an effective soil remediation technology, has gained popularity in the past ten years both in developed and developing countries. The main goal of the current article is to improve the understanding of phytoremediation of organic pollutants with emphasis on hydrocarbons. To design phytoremediation systems and also enhancement of their efficiency, either in laboratory or in field experiments, there is a serious need for better knowledge of phytoremediation mechanisms and also of factors affecting phytoremediation. In addition to phytoremediation applications, advantages, and limitations, its mechanisms and related new developments have been discussed in this article.
Show more [+] Less [-]Metal Signature of Atmospheric Aerosol from Kochi, the Queen of Arabian Sea, Kerala, India
2016
K, Gayathree Devi | P.S., Akhil | C.H., Sujatha
The present research article highlights the metal (Cd, Cu, Pb, Zn and Fe)distribution pattern in the RSPM generated in different hot spot sites located at Kochi, theQueen of Arabian Sea. These sampling sites are categorized under three different zonesas estuarine, riverine, and coastal. Two sampling phases are selected in order to check theconsistency in pollution trend after a two year gap and are described in Phase I and PhaseII, respectively. Metals are noticed to be intensely concentrated in the post monsoonmonths in both phases. Among the metals, Fe is revealed as the prominent metal at theestuarine sites. Estuarine and riverine zone expresses the overall enrichment pattern withslight difference at coastal regime in phase I. In phase II, insignificant metal load withirregular pattern is observed. Source apportionment study reveals that major sources ofmetals are from automobile exhausts and the estuarine zone is entangled with 45.9%.
Show more [+] Less [-]Quality Analysis of Drinking Water Provided for the Readymade Garment Workers in Dhaka, Bangladesh
2016
Hassan, Mahmud | Islam, S. M. Didar-Ul | Ahmed, Fahad | Rahman, Mirza A.T.M. Tanvir
Readymade garment industries are the prominent economic sector for Bangladesh as well as scoping the huge working area for workers. But health condition of workers, drinking water quality, and proper maintenance of the environmental parameters are not well monitored. This study aims to assess the physio-chemical and bacteriological quality of drinking water provided for the garment workers in Dhaka. Ten garment industries were pre-selected for the water quality analysis and three drinking water samples from each industry were taken for further analysis. Physio-chemical parameters viz pH, TDS were measured by probe method and Total harness and Chloride of the water samples were measured by titrimetric method, respectively. Biological parameters viz Total coliforms, Fecal coliforms, Total aerobic bacteria count, Fecal streptococci, Pseudomonas spp., and Vibrio Cholerae were determined through standard procedure. Results show that pH (6.7±0.05 to 7.4±0.20), TDS (126.2±8.42 to 217.9±3.60 mg/L), Total Hardness (92±7.07 to 275±21.22 mg/L), and Chloride (8.5±0.95 to 46.5±3.27 mg/L) are within the acceptable limit. Bacteriological results show that Total coliform (1.05×103±0.071×103 to 2.16×103±0.084×103 CFU/100 ml), Fecal coliforms (145±2.828 to 249±21.213 CFU/100 ml), and Total aerobic bacteria count (2152.5±399.51 to 5540.5±185.97 CFU/100 ml) are higher than the standard limits. Pseudomonas spp. was also present in all drinking water samples but Fecal streptococci and Vibrio Cholerae were absent in all water samples. Bacteriological analysis shows that sources of drinking water are contaminated and proper maintenance and screening facilities should be improved.
Show more [+] Less [-]Assessing Indoor Air Pollution within Different Areas of Female Beauty Centers and Exploring Their Relation to Various Respiratory Symptoms
2016
Almarshad, Saja
The staff working at beauty centers are exposed to various chemicalproducts used daily in their working environment. Both hair dressers and nail techniciansare exposed to chemicals that are known to have an influence on the respiratory system.In order to evaluate such influence, this cross-sectional observational study wasconducted on a randomly selected 14 beauty centers in Dammam City, Saudi Arabia. Atthe investigated salons, both of respiratory symptoms and the quality of air wereevaluated and data were analyzed statistically. 40.5% out of the 79 subjects included inthe study were hairdressers, 17.7% were nail technicians and (41.8%) were working inboth of the previously mentioned areas as part of their everyday practice. The staffcomplained of respiratory symptoms which include dyspnea, cough, phlegm, wheeze, andshortness of breath. Both hairdressers and nail technicians developed respiratorysymptoms while working in the salons. Indoor Air pollution was assessed and many datawere out of the normal standard ranges which include: relative humidity (RH), volatileorganic compounds (VOC), carbon dioxide (CO2), and ammonia (NH3). We conclude thatgood ventilation is required to reduce the influence of such substances on the respiratorysymptoms of the staff working at salons.
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