Radionuclides proportion and radiological risk assessment of soil samples collected in Covenant University, Ota, Ogun State Nigeria

The activity levels of 238U, 232Th and 40K in soil surrounding major office complexes in Covenant University were analyzed for radiological hazards to determine the safety of the residents in such environment. Sixteen (16) soil samples were collected, prepared and sent to Acme laboratory in Canada for analysis with the use of high purity germanium detector. The mean activity concentrations of 238U, 232Th and 40K were found to be 45?±?10, 135?±?8 and 195?±?20 respectively. The concentrations of 238U and 232Th were found to be higher than the world recommended standard of 35 and 30, while the result for 40K was noted to be lower than the world safe limit. The average values of Raeq, D, AED, Iyr, Hex and ELCR in this study were estimated to be 252.33?Bq/kg, 110.15 nGy/h, 0.13 mSv/y, 1.78, 0.68 and 0.47?×?10-3 respectively. It was noticed that none of the measured parameters was higher than the internationally recommended safe limits. 232Th was found to be the major contributor to the environmental radionuclides in the area of study. Therefore, the inhabitants of the office complexes whose environment was assessed are considered not be exposed to any radiological hazards

Removal of emerging pollutants in conventional and microalgae based biotechnology urban wastewater treatment plants

Wastewater treatment plants (WWTPs) reduce portion of the input of pharmaceuticals in aquatic systems, but there is no data available about the elimination of emerging contaminants with microalgae technology. The aim of this work was to determine the average mass flows and concentrations of pharmaceuticals in influents and effluents from two sewages treatment plants using conventional and microalgae based biotechnologies and to compare the removal of pharmaceuticals using both depuration technologies. Only between 20 to 60% of five pharmaceuticals groups is reduce in both WWTP using conventional technologies consisting of a pretreatment, primary settling and secondary treatment by aerobic biological reactor. Using microalgae based biotechnologies efficiency of removal pharmaceuticals is higher than conventional technologies and it increase by using DAF (Dissolve Air Flotation) technology to separate algae biomass

Application of trophic state indices in the dam of Salto Grande

Eutrophication is the process by which nutrients, mainly phosphorus, are contributed. Currently, this has increased due to human activity and population growth which has caused the deterioration of water quality and limited its potential uses. In this study, the trophic state of the Salto Grande Reservoir was determined in the stretch between Monte Caseros/Bella Union and the dam, during the summer period of 2010 through the application of different indices. Moreover, the representative blue green algae from the area corresponding to the genera Microcystis and Dolichospermum and their relation to the nutrients were studied. Nutrient concentrations, mainly phosphorus, were relatively high, determining an eutrophic state from the area of study. Due to the flooding which began in November 2009, the relative abundance of cyanobacteria was not high, with a maximum of approximately 40,000 cells/ml. Furthermore, no linear correlation was established between cyanobacteria and the nutrients studied. We conclude that, as suggested by the records, nutrients would not be a limiting factor for the proliferation of cyanobacteria in the reservoir area of Salto Grande.La eutrofización es un proceso de aporte de nutrientes principalmente de fósforo. Actualmente, se encuentra acrecentado por las actividades antrópicas y crecimiento poblacional que provoca un deterioro de la calidad del agua limitando sus usos potenciales. En este trabajo se determinó el estado trófico en el río Uruguay, en el tramo comprendido entre Monte Caseros/Bella Unión y la represa, durante el período estival 2010 a través de la aplicación de diferentes índices. Además, se estudiaron las cianobacterias representativas del área correspondientes a los géneros Microcystis y Dolichospermum y su relación con los nutrientes. Las concentraciones de nutrientes fueron relativamente elevadas, principalmente el fósforo, determinando un estado eutrófico para el área de estudio. Debido a las crecientes iniciadas en noviembre de 2009, la abundancia relativa de cianobacterias no fue alta, tuvo un máximo de aproximadamente 40.000 cél/ml. Por otro lado, no se estableció una correlación lineal entre las cianobacterias estudiadas y los nutrientes. Se concluye que, como indican los antecedentes, los nutrientes no serían un factor limitante para la proliferación de cianobacterias en el área del embalse de Salto Grande.Fil: Crettaz Minaglia, Melina Celeste. Universidad Autónoma de Entre Ríos. Facultad de Ciencia y Tecnología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Bordet, Hugo Facundo. Universidad Nacional de Entre Ríos. Facultad de Ciencias de la Alimentación; Argentina. Complejo Hidroelectrico de Salto Grande. Área de Gestión Ambiental; Argentin

Physicochemical Evaluation of the Upper Litani River Watershed, Lebanon

This study aims to determine the extent of groundwater damage in the Upper Litani River Basin (ULRB) after years of water mismanagement and overfertilization in what is considered to be Lebanon's largest fertile area. Physical and chemical samples were collected between 2005 and 2010 and analyzed using “The Standard Methods for the Examination of Water and Wastewater” (APHA, AWWA) in order to determine the extent of this pollution. The parameters included pH, ammonia, nitrate, nitrite, sulfate, phosphate, dissolved oxygen, and total dissolved solids

Plant tissue extraction method for complexed and free cyanide

A method for free cyanide and strongly-complexed cyanide measurement within plant tissue was developed to study uptake and movement of cyanide species separately from cyanide metabolism and metabolite movement by a willow plant (Salix eriocephala var. Michaux). Spike recoveries from solutions with and without plant tissue, using various solvent combinations, and background control tissue contributions were investigated to obtain an accurate and precise extraction method for measurement of complexed and free cyanide concentrations within plant tissue. The optimum extraction technique involved the freezing of plant tissue with liquid nitrogen to facilitate homogenization prior to extraction. Homogenized willow tissue samples, 1 to 1.5 g-fresh weight, were ground a second time under liquid nitrogen followed by grinding in slurry with 2.5 M NaOH. The slurry was brought to 100 mL volume, sonicated for 5 min, extracted in the dark for 16 h, and analyzed without filtration for total and free cyanide by acid distillation and microdiffusion respectively. Sample tissue extraction controls found recoveries of 89% and 100% for 100 µg L-1 CNT as KCN and K4Fe(CN)6 spiked in willow tissue slurries. Methanol, hexane, and 2-octanol inclusion in the solvent matrix with 2.5 M NaOH interfered with the cyanide analytical technique while chloroform reacted with NaOH and free cyanide in solution. Filtration was not included due to increased cyanide loss, and analysis of control tissue showed minimal release of cyanide or interference of plant tissue with the cyanide analytical method.Tissue cyanide concentrations from hydroponicallyexposed tissue using the optimal extraction method agreed with tissue cyanide stable isotope (15N) results

Acute toxicity of Gammalin 20 to Chrysichthys nigrodigitatus (Lacepede)

The impact of acute exposure of Gammalin 20 (an organochlorine pesticide) was investigated in a static bioassay test over a 96-(4-day) period on the fingerlings of Chrysichthys nigrodigitatus (lacepede). The 96-hLC sub(50) of Gammalin 20 was determined as 2.31 Ug/l with lower and upper limits of toxicities as 2.10 and 4.44 Ug/l respectively. At higher concentrations, the colour of the exposed fish became darker, opercular movement slowed down while pigmentation pattern increased and respiratory distress was observed, erratic swimming, tonic convulsion and no response to gentle prodding, and finally death. The implications of these results were discussed with a suggestion of the total ban on the use of Gammalin 20 in capture fisheries due to its harmful and persistence nature in the aquatic environmen

Acute toxicity of synyhetic resin effluent to African Catfish, Clarias gariepinus [BURCHELL, 1822].

Aquatic pollution as a field has gained a lot of attention over the decades majorly because of the vital role the aquatic environment plays in the human lifecycle. Indusrial wastewaters are often generated and discharged into the environment without treatment. Toxicity of effluents from Synythetic Resin production plant were evaluated in this study. Acute toxicity (96-h LC50) was evaluated using 0.23, 0.31, 0.35 and 0.39 mg/L of the effluent in a renewal bioassay procedure. Physicochemical parameters of the effluent were also evaluated, the values obtained for lead, cyanide, total suspened solid, total hadness, total dissolved solids and alkalinity were higher than the Federal Environmental Protection Agency standard specification for effluent discharge into aquatic environment and as such contributed to the effluent's toxicity. Mortality increased as the concentrations of the effluent increases and 0.355mg/L was obtained as LC50. The research eventually revealed that the synthetic resin effluent has a high level of toxicity to catfish. Deleterious effects such as biomagnification and other abberations may occur in man if exposed to substantial concentration of the effluent

Building forecast maps of water quaůity for main rivers and canals in Tien Giang province, Vietnam

This study aims to enhance the mapping of forecast for water quality assessment in Mekong Delta provinces. The data from 32 sites from main rivers and canals in an area of around 2,482 km2 in Tien Giang Province, Vietnam, were used for calculation and mapping. The ArcGIS 9.3 software, Inverse Distance Weighting (IDW) interpolation method, hydrologic data, and water quality parameters in March (2010-2014) were applied to build the maps showing 2020 water quality predictions for main rivers and canals in Tien Giang Province. The estimation was based on the Water Quality Index (WQI) with 6 parameters such as pH, total suspended solid (TSS), dissolved oxygen (DO), biochemical oxygen demand (BOD), total nitrogen (T_N), and coliform. The results showed that water quality in the studied area in dry season will not be improved by the year 2020. The finding could be a scientific reference for the selection of effective approaches to improve water quality in main rivers and canals in Tien Giang Province

Zooplankton from Can Giuoc River in Southern Vietnam

In this study, the variables of zooplankton and water quality were investigated in the Can Giuoc River, Southern Vietnam. Zooplankton was monitored in April and September 2015 at 5 sampling sites in the river. Some basic water quality parameters were also tested, including pH, total suspended solid (TSS), dissolved oxygen (DO), biological oxygen demand (BOD5), inorganic nitrogen (NH4+), dissolved phosphorus (PO43-), and coliform. The zooplankton biodiversity indices were applied for the water quality assessment. The results showed that pH ranged from 6.7 to 7.6 during the monitoring. The TSSs were between 34–117 mg/L. The DO and BOD5 were from 0.6 to 3.8 mg/L and from 6.3 to 13.2 mg/L, respectively. The NH4+ and PO43- concentrations ranged from 0.44 to 3.23 and from 0.08 to 1.85 mg/L, respectively. The coliform number was between 9.3x103–9.3x104 MPN/100 mL. The zooplankton analyses showed that there were 31 species of coelenterates, rotatoria, oligochaetes, cladocerans, copepods, ostracods, mysidacea, and 8 larval types. Thereof, the species of copepods were dominant in the species number. The zooplankton density ranged from 9 500 to 23 600 individuals/m3 with the main dominant species of Moina dubia (Cladocera), Thermocyclops hyalinus, Acartia clausi, Oithona similis (Copepoda), and nauplius copepods. The biodiversity index values during the monitoring were from 1.47 to 1.79 characteristic of mesotrophic conditions of the aquatic environment. Besides, the species richness positively correlated with pH, TSS, DO, BOD5, NH4+, PO43-, and coliform, while the zooplankton densities got a positive correlation with DO, BOD5, NH4+, PO43-, and coliform. The results confirmed the advantage of using zooplankton and its indices for water quality assessment