Evaluation of biological activity of some dioxouranium complexes of some Schiff base and dithiocarbamate ligands

A number of dioxouranium(VI), UO22+ complexes of Schiff base and monodithiocarbamate ligands have been synthesized and characterized. Antimicrobial activities of these complexes have been studied. The results of inhibition zones of the selected microorganisms showed that all complexes exhibited mild to prominent activities against the pathogens tested herein.</p

Pollution Status of Trace Metals in Groundwater Due to Industrail Activities in and Around Dhaka Export Processing Zone, Bangladesh

Effluents from multiindustrail activities influence inland water system directly, which subsiquently affect groundwater quality and human health. Some previous reports indicated that inadequate treatment process of discharged effluent of Dhaka Export Processing Zone (DEPZ) increased the concentrations of pollutants in surface water system and deteriorated total fishing and agricultural system around DEPZ and its connected area. Therefore, the present study was conducted to investigate wether the concentration of selective metals viz. Li, V, Cr, Co, Ni, Cu, Zn, Ga, As, Se, Rb, Sr, Ag, Cd, Cs, Ba, Pb and U in two types of groundwater sources were either with in the permissible guidlines or influenced by DEPZ multi industrail on their levels of contamination. The concentrations of metals were determined using inductively Couples Plasma Mass Spectrometry (ICP-MS). The mean concentrations of the elements in both types of groundwater were in the levels of their permissible guidlines, except for Ni (12.91 µg/L), Ga (0.48µg/L), Sr (90.26 µg/L) and Cs (0.07µg//L)in groundwater inside DEPZ, which were 1.30, 5.00, 1.50 and 1.40 times higher than the maximum permissible limit (MPL) of 10 µg/L, 0.09 µg/L, 60 µg/L, and 0.05µg/L, respectively. The mean concentrations of Li (6.85 µg/L), Zn(268 µg/L), Ga (0.12 µg/L), Sr (131 µg/L) and Cs (0.07 µg/L) were 3.43, 1.34, 1.33, 2.18, 1.40 times higher then the MPL of 2 µg/L, 200 µg/L, 0.09 µg/L, 60 µg/L and 0.05 µg/L, respectively, in groundwater around DEPZ. Comparatively Zn and Sr possessed higher concentrations, and Cs and U possessed lower concentration in both types of groundwater sources. The elements were distributed in homogeneous and hetrogeneous manner among the source points for deep-tubewell (DTWS) and shallow tubewell (STWs), respectively. The significant positive correlations were found between the elements viz., Co-V (0.85), Ni-Sr ((0.70), Co-Cd (0.86), As-Se (0.99), Cs-Zn (0.95), Li-U (0.,71), Zn-U (0.69), Ga-U (0.77), Sr-Pb (0.85) and Ba-Ag (0.99) in the grounwater samples inside DEPZ, and for Cu-Cs (0.78), Cu-Ba (0.73), Pb-Cu (0.69), Cu-U (0.70), Cr-Cd (0.71), Ni-Cu (0.83), Ni-Se (0.70), Li-Se (0.72), Li-Cd (0.84), Cu-V (0.78), V-Ga (0.82), Sr-V (0.68), Ba-V (0.67), Zn-Ga (0.75), Zn-Ag (0.69), Se-Ga (0.67), As-Rb (0.84), Se-Ba (0.67), Sr-Ba (0.79), Sr-Pb (0.71), Cs-U (0.83) and Pb-Ba (0.98) in the groundwater around DEPZ at 0.05 to 0.01 level. Considering the elemental load, it was assumed that the groundwater of DTWs inside DEPZ are still isolated from potential contaminated sources, whereas groundwater of STWs around DEPZ seemed to be gradually affected by the sources of these toxic trace metal

Stagnant surface water bodies (SSWBs) as an alternative water resource for the Chittagong metropolitan area of Bangladesh: physicochemical characterization in terms of water quality indices

金沢大学理工研究域物質化学系The concern over ensuing freshwater scarcity has forced the developing countries to delve for alternative water resources. In this study, we examined the potential of stagnant surface water bodies (SSWBs) as alternative freshwater resources in the densely populated Chittagong metropolitan area (CMPA) of Bangladesh-where there is an acute shortage of urban freshwater supply. Water samples were collected at 1-month intervals for a period of 1 year from 12 stations distributed over the whole metropolis. Samples were analyzed for pH, water temperature (WTemp), turbidity, electrical conductivity (EC), total dissolved solids, total solids, total hardness, dissolved oxygen (DO), chloride, orthophosphates, ammonia, total coliforms (TC), and trace metal (Cd, Cr, Cu, Pb, As, and Fe) concentrations. Based on these parameters, different types of water quality indices (WQIs) were deduced. WQIs showed most of CMPA-SSWBs as good or medium quality water bodies, while none were categorized as bad. Moreover, it was observed that the minimal water quality index (WQIm), computed using five parameters: WTemp, pH, DO, EC, and turbidity, gave a reliable estimate of water quality. The WQIm gave similar results in 72% of the cases compared with other WQIs that were based on larger set of parameters. Based on our finding, we suggest the wider use WQIm in developing countries for assessing health of SSWBs, as it will minimize the analytical cost to overcome the budget constraints involved in this kind of evaluations. It was observed that except turbidity and TC content, all other quality parameters fluctuated within the limit of the World Health Organization suggested standards for drinking water. From our findings, we concluded that if the turbidity and TC content of water from SSWBs in CMPA are taken care of, they will become good candidates as alternative water resources all round the year. © 2010 Springer Science+Business Media B.V