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Survey and Analysis of Noise Pollution in the Bidboland Gas Refinery Полный текст
2016
Noorpoor, A. R. | Bayatian, M. | Motaghed, S. | Jamshidi Moghadam, A. | Rahmati, N.
We investigated the issue of noise pollution in the Bidboland gas refineryby noise measurement and surveys. The Bidboland gas refinery has several process units.The sound pressure levels were measured at several places, such as units of 200, 300,400, 500, boiler, powerhouse area, cooling towers pumps, and maintenance area, and thecorresponding noise maps were produced by using sound plan software. We identified thesources of noise pollution. We first measured the mean A-weighted sound pressure levelin each study unit and analyzed the obtained data in Microsoft Excel. The noisiest unitswere identified and some suggestions were offered to reduce the sound exposure level. Itwas specifically noted through the surveys that the noise levels detected in all testedindustries was much above 80 dBA limit specified by regulations. In lieu, variousmeasures to control the noise pollution were contemplated and discussed.
Показать больше [+] Меньше [-]Public health risk assessment of chromium intake from vegetable grown in the wastewater irrigated site in Bangladesh Полный текст
2016
Ahmed, Fahad | Hossain, Md. Shakhaoat | Abdullah, Abu Tareq | Akbor, Md. Ahedul | Ahsan, Md. Aminul
There are many potential risks to human health from heavy metal contamination of vegetables resulting from wastewater irrigated sites. This study was carried out to assess the concentration of chromium (Cr) and the risk to human health by chromium through the intake of locally grown vegetables collected from wastewater irrigated agricultural fields. Twenty-seven samples of 9 (nine) different types of vegetables were analyzed by an Atomic Absorption Spectrometer (AAS) (Varian AAS 240 F S). The range of chromium concentration in wastewater irrigated vegetables was ND (Not detected) -4.14mg/kg. The highest mean concentration of chromium (4.14 mg/kg) was detected in radish. The mean concentration of chromium in all the vegetables was within the safe limits of WHO/FAO except radish which was much higher than the standard. Health risk index for chromium contamination in all vegetables was less than 1 for both adults and children which cause no risk to the local population. Among all vegetables tested, the highest intake value of chromium was from consumption of radish for both adults and children. The lower values of health risk index indicated chromium contamination in the wastewater irrigated vegetables that cause less negative impact on human health.
Показать больше [+] Меньше [-]Modeling for vehicular pollution in urban region; A review Полный текст
2016
Kumar, Awkash
Air pollution is one of the major threats to environment in the present time. Increase in degree of urbanization is a major cause of this air pollution. Due to urbanization, vehicular activities are continuously increasing at a tremendous rate. Mobile or vehicular pollution is predominantly degrading the air quality worldwide. Thus, air quality management is necessary for dealing with this severe problem. The first step to deal with this air pollution problem is to find out the existing concentration of air pollutants in the atmosphere due to vehicular activities. It is not possible to establish ambient air monitoring stations everywhere, especially in developing countries as it is a costly process. Hence, vehicular air quality models are used to predict the concentration of different pollutants in the atmosphere. This review covers the simulation of vehicular emission by different types of models for estimating the pollutant concentration in ambient air from vehicular emissions. The models predict concentrations of pollutants in time and space and relate it to the dependent variables. These can also be used to predict the concentration of pollutants in the future. These models can be useful for imposing regulations by governments and to test techniques for controlling pollutant emissions. This review also discusses where and how the respective models can be used.
Показать больше [+] Меньше [-]Assessment of major ionic compositions and anthropogenic influences in the rainwater over a coal mining environment of Damodar River basin, India Полный текст
2016
Mahato, Mukesh | Singh, Prasoon | Singh, Abhay | Tiwari, Ashwani
In the present study, 45 rainwater samples were collected from February to December 2012 on event basis in East Bokaro coal mining environment. Physico-chemical and major ionic compositions of rainwater samples as well as water soluble major ion composition were analyzed to employ principle component analysis for source identification. The average pH value was recorded 6.1 and varied from 5.1 to 6.9 in the collected rainwater samples, indicating slightly acidic to alkaline in nature. The rainwater chemistry of the region showed high contribution of HCO3- (32%) followed by SO42- (30%), Cl- (20%), NO3- (15%) and F- (3%) in anionic abundance. In case of major cations, Ca2+ (29%) was dominant followed by Mg2+ (27%), NH4+ (22%), Na+ (18%) and K+ (4%). The ratio of Cl-/Na+ in the rainwater samples was found to be almost equal to sea water. Higher enrichment of Na+ and Cl- concentration may be due to marine contribution. The EFs were found to be high for HCO3-, Ca2+, SO42- and K+ indicating sources other than sea; i.e., coal mining and other anthropogenic activities. The principle component analysis for ionic source identification was synthesized into four factors with eigen values cut off at greater than unity and explained about 71.8 % of the total variance. The rainwater quality area is mainly influenced due to mining activities, vehicular pollution and industrialization in the East Bokaro coalfield area.
Показать больше [+] Меньше [-]Analysis of Chemical and Microbial Contents of Public Swimming Pools’ Water in Akwa Ibom State, Nigeria Полный текст
2016
Antia, Mfon | Umoh, Akaninyene
This study assessed the chemical and microbial contents in the water of public swimming pools in Akwa Ibom State, Nigeria. A total of 16 public pools were selected through probability sampling from the 32 pools that existed in the five urban areas of Akwa Ibom State. Water samples were collected from the sampled pools and tested in the laboratory for chemical and microbial contents. Results showed that the chemical contents of most pools in the study area were less than the values recommended for effective disinfection of the pools. Average free chlorine ranged from 0.05 mg/L to 1.15 mg/L 200 Cfu/ml permissible, except for pools L and M, with 1.8×102 Cfu/ml and 1.7×102 Cfu/ml, respectively. Mean fecal coliform ranged from 2.0×103 Cfu/ml to 4.4×103 Cfu/ml >10 Cfu/100 ml permissible, except for pools L and M, with 0.0 Cfu/ml. It could therefore be concluded that only one out of every eight public swimming pools in Akwa Ibom State meet the minimum requirement for both chemical and microbial contents. This simply implies that most public swimming pools in the study area are not safe for users.
Показать больше [+] Меньше [-]Investigation of Spatial Structure of Groundwater Quality Using Geostatistical Approach in Mehran Plain, Iran Полный текст
2016
Khosravi, Hassan | Karimi, Kamran | Nakhaee nejadfard, Sara | Mesbahzadeh, Tayebeh
Groundwater is a major source of water for domestic, industrial, and agricultural sectors in many countries. The main objective of this research was to provide an overview of present groundwater quality using parameters such as calcium, magnesium, sodium, chloride, sulfate, pH, and electrical conductivity (EC) in the Mehran plain, Ilam province using GIS and geostatistical techniques. A total of 23 deep and semi-profound wells were selected based on the classified randomized sampling method. The sampling locations were obtained by GPS. Plastic containers were used for the collection of water samples. These samples were transferred to the laboratory for analyzing water quality parameters. Statistical characteristics, qualitative data interpolation, and zoning were investigated using SPSS 20 ،GS+5.3 and ArcGIS10.1. Kolmogorov–Smirnov test were used to test data normality. In order to normalize parameters, logarithm, and 1/x were used for sulfate, EC, cation, and anion. Then the variogram analysis was performed to select the appropriate model. Results showed that co-kriging is the best method for cation and anion, whereas local polynomial interpolation is suitable for sulfate. The results of the interpolation of groundwater quality factors showed that there is approximately good adaption among groundwater factors and geomorphology and topology of the region. Because of inappropriate irrigation system, the highest concentration is in the northwest and western parts of the region, where there is the minimum height and maximum agricultural land. Growth of arable land and agricultural activities has caused increasing concentrations of studied elements, especially EC.
Показать больше [+] Меньше [-]Alterations in the Plasma Thyroid and Cortisol Hormones in Yellowfin Sea bream, Acanthopagrus latus, following exposure to Benzo(α)Pyrene Полный текст
2016
Alijani Ardeshir, Rashid | Rastgar, Sara | Movahedinia, Abdol-Ali | Yarahmadi, Zahra
The goal of this research is to study the effect of benzo-alpha-pyrene (BαP) as a pollutant on the plasma levels of cortisol, thyroxin (T4), and triiodothyronine (T3) hormones, and the T3/T4 ratio in the yellowfin sea bream, Acanthopagrus latus. The BαP (50 mg kg-1) in vegetable oil was peritoneally injected. Blood samples were obtained from the treated and control groups after 3 and 72 hr, respectively. The amounts of cortisol, T3, and T4 were measured using the ELISA techniques. The results showed that during both the 3 and 72 hr BαP exposures, the T4 hormone levels significantly decreased, although the cortisol levels increased (P<0.05). However, the T3 hormone levels and T3/T4 ratios compared with their control groups showed a significant difference just after 72 hr (P<0.05). The disruptive effects of the BαP exposure on T4 was stronger than that on the T3, being more evident in long-term stress. Thus, the BαP exerts a significant effect on the thyroid endocrine system and consequently on fish metabolism and growth.
Показать больше [+] Меньше [-]Contamination by trace elements of agricultural soils around Sidi Bou Othmane in abandoned mine tailings in Marrakech, Morocco Полный текст
2016
Yassir, Barkouch | Sana, El Fadili | Alain, Pineau
This study was carried out for the purpose of investigating the issue of tailings dams as a potential source of contamination by trace elements in soils at the Sidi Bou Othmane mine in the Marrakech Region, Morocco. Soil samples taken from depths of up to 15 cm and within a radius of 50 m from the tailings dams, were analyzed for Cd, Cu, Pb and Zn using atomic absorption spectrometry. Average concentrations of Cd, Cu, Pb and Zn in soils around the abandoned tailings dams were, respectively, 157.2±8.8, 969.1±38.7, 1640.7±42.7 and 2846.8±84.6 mg/kg. Soils in the vicinity of the decommissioned tailings dams registered increased values for Cd, Cu, Pb and Zn. Contamination factors (CF) and pollution index (PI) were calculated in order to estimate the anthropogenic contribution of target pollutants which determined Cd, Cu, Pb and Zn as the main pollutants in this region. The results revealed the polluted areas in the vicinity of the mine, especially two rural communities apparently linked to the lack of appropriate measures to counteract the effects of these mine tailings, which were causing a progressive contamination of the soil with residues of heavy metal emissions in this region under study. Improved strategies for the management of tailings, among other factors, might have influenced the reduced level of contamination by trace elements at the abandoned mine tailings dam sites.
Показать больше [+] Меньше [-]On the Seasonal Changes in the Surface Water Chemistry of Museum Lake, Thiruvananthapuram, Kerala, India Полный текст
2016
Ajayan, Anila | Kumar, Ajit
The surface water chemistry of Thiruvananthapuram Museum Lake was carried out in the period of February 2013 to January 2014. Correlation study of the parameters and overall CCME WQI (Canadian Council of Ministers of the Environment Water quality Index) was also prepared in the study for the lake water. The parameters analysed are cations such as Ca2+, Na+, Mg2+ and K+ and the anions like PO4-, Si4- , NO3- and NO2-. Abiotic factors like water pH, Temperature, Conductivity, TDS, Total Alkalinity and Total Hardness were also analysed. The pH ranged between 6.5 to 7.4. The total hardness ranged between 50.8-99 mg/L which shows the water is moderately hard one. During the pre monsoon period, water temperature showed a positive correlation with total alkalinity (r= 0.915) pH (r= 0.841) and TDS (0.876). Dissolved Oxygen (DO) value showed a positive correlation with Biological Oxygen Demand (BOD) (r= 0.999). The overall CCME water quality index was 80.81 which indicate the water body is protected with only a minor degree of threats. The quality of the water is an essential element of the Thiruvananthapuram Zoo environment with respect to both healths of the ecosystem and zoo tourism enjoyment. Moreover, if maintained properly, this water body can be treated as a major drinking water source for the zoo animals.
Показать больше [+] Меньше [-]Adsorption of arsenic on soil under different soil moisture conditions Полный текст
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.
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