In ecological risk assessment for chemical pollutants, it is important to quantify the concentrations of freely dissolved substances in aqueous samples for approximate characterization of the bioavailable fraction. Such measurements are important because the concentration and toxicity of a chemical in an organism’s body are linked to the bioavailable fraction and its chemical form within the su...

−Cross-linked chitosan/bentonite composite (CCB) was prepared, and characterized by Fourier transform infrared (FTIR) spectroscopy, BET surface area and pore diameter analyses, X-ray diffraction (XRD) patterns and thermal gravimetric analyses (TGA). The adsorption of hexavalent chromium Cr(VI) onto CCB as a function of adsorbent dosage, initial Cr(VI) concentration, solution pH, and contact tim...

In the present research, the potential of two biochars produced by the thermal decomposition of wheat straw (BCS) and wicker (BCW) for Cr(VI) ions removing from wastewater was investigated. The pH and the presence of chlorides and nitrates were also investigated. The Freundlich and Langmuir models were applied for the characterization of adsorption isotherms. The Langmuir model has better fitti...

We previously showed that carcinogenic nickel, arsenic, and chromium(VI) compounds induced anchorage independence (AI) in diploid human fibroblastic cells (HFC) derived from foreskins (K. A. Biedermann and J. R. Landolph, Cancer Res., 47: 3815-3823, 1987). To elucidate the role of the valence state of chromium and solubility of chromium compounds in inducing AI, we studied the ability of solubl...

chromium (cr) is one of the elements presents in crust of the earth. due to its toxicity, chromium is considered as water contaminant that may disturb metabolic activity. in the present study, adsorption of dissolved chromium (vi) onto elaeagnus angustifolia fruit charcoal, jujube fruit charcoal and the standard granular activated carbon (gac) has been investigated and compared. the effect of c...

A sensitive spectrophotometric method for the determination of trace amounts of chromium(VI) is described. Chromium(VI) forms chlorochromate anion in the presence of acid and chloride ion. The formed anion is extracted in toluene as ion-pair with a cationic dye rhodamine 6G. At 535 nlll absorption maximum molar absorptivity is 2x104 I mol-I em-I. The colour is stable for 4 h and the system obey...

The removal of the chromium (VI) ion from aqueous solutions with the Lewatit FO36 ion-exchange resin is described at different conditions. The effects of adsorbent dose, initial metal concentration, contact time and pH on the removal of chromium (VI) were investigated. The batch ion exchange process was relatively fast and it reached equilibrium after about 90 min of contact. The ion exchange p...

Possible application of a locally isolated environmental isolate, Acinetobacter haemolyticus to remediate Cr(VI) contamination in water system was demonstrated. Cr(VI) reduction by A. haemolyticus seems to favour the lower concentrations (10-30 mg/L). However, incomplete Cr(VI) reduction occurred at 70-100 mg/L Cr(VI). Initial specific reduction rate increased with Cr(VI) concentrations. Cr(VI)...

It is well known that soluble chromates, when added to blood in vitro or in vivo, hardly interact with the plasma components and easily penetrate the erythrocytes, and that reduction to the trivalent species follows.1-3) However, in vitro reduction of chromium(VI) in human4) and rat5) plasma has been observed. Some problems of the fate of chromium(VI) in blood, especially in vivo remain unsolve...

105 ABSTRACT: The isolated fungi species of different kinds from chromium contaminated soil sites located in Nagalkeni, Chennai were used for reducing chromium(VI) in a tannery industry wastewater of Nagalkeni, Chennai. The experiments were conducted to know biosorption potential of isolated fungi species for removing chromium(VI) in a tannery industry wastewater against the different pH, fungi...