Hexavalent chromium [Cr(VI)] in industrial effluent is one of the most serious environmental problems in India and also in other countries. Micellar-Enhanced Ultrafiltration (MEUF) of the chromate anions from aqueous solutions has been studied at room temperature (28±2°C) using cationic surfactants, cetyltrimethylammonium bromide (CTAB) and cetylpyridinium chloride (CPC), micelles of which adso...

Concentrations of 0.25 and 0.5 mug/ml calcium chromate (CaCrO4-2H2O)dissolved in Dulbecco's medium were found to alter the growth behavior of BHK21 cells in culture. Treated cells grew as shortened fibroblasts and in random orientation. The changes detected during the first two weeks of culture in the presence of the metal became more pronounced as the number of growth passages increased. In ad...

Corrosion is the degradation or deterioration of metal components due to a reaction with the environment. Chromate conversion coating is applied to passivate metallic surface to slow down (and prevent to some extent) corrosion process. Chromate conversion process uses chromium compounds including hexavalent chromium, which is toxic, carcinogenic and hazardous to human health and environment. He...

Sequential reduction of chromate and nitrate, two competitive electron acceptors, has been demonstrated for strains of Pseudomonas genus for both planktonic cells and cells immobilised in agar layers on the surface of synthetic membrane. Denitrification occurs practically after chromate depletion. This order of reduction process is consistent with redox potentials of the respective reactions. I...

A pseudomonad (CRB5) isolated from a decommissioned wood preservation site reduced toxic chromate [Cr(VI)] to an insoluble Cr(III) precipitate under aerobic and anaerobic conditions. CRB5 tolerated up to 520 mg of Cr(VI) liter(-1) and reduced chromate in the presence of copper and arsenate. Under anaerobic conditions it also reduced Co(III) and U(VI), partially internalizing each metal. Metal p...

The potential role of iron and copper and the involvement of hydroxyl radicals in the DNA cleavage caused by chromate and glutathione (GSH) has been investigated. We have also studied the ability of chromate, on reaction with ascorbate as well as in mixed solutions of ascorbate and GSH, to cause DNA strand breaks. In both fully demetalated and conventional (i.e., metal contaminated) systems, ch...

It is possible to partially transform the silver chromate precipitate present in Golgi stained structures into lead chromate. When this partial replacement is followed by a treatment in a solution containing thiosulphate ions, only lead chromate is left in the tissue. This results in a depleted impregnation of the originally Golgi stained structures without fading of their borderlines. The tiss...

SCOEL has already issued Summary Documents on both Lead and Lead Compounds (SCOEL/SUM 83) and Hexavalent Chromium Compounds (SCOEL/SUM 86), to which reference is made. On this basis, the present Summary Document on Lead Chromate is focussed on experimental data on the genotoxicity of lead chromate and on the issue of bioavailibility. Specific data on lead chromate published after the latest IAR...

SCOEL has already issued Summary Documents on both Lead and Lead Compounds (SCOEL/SUM 83) and Hexavalent Chromium Compounds (SCOEL/SUM 86), to which reference is made. On this basis, the present Summary Document on Lead Chromate is focussed on experimental data on the genotoxicity of lead chromate and on the issue of bioavailibility. Specific data on lead chromate published after the latest IAR...

Ochrobactrum tritici 5bvl1 is able to resist to high concentrations of chromate through the expression of an inducible chromate-resistant determinant, found in a mobile element (TnOtChr), which carries the genes, chrB, chrA, chrC and chrF. The regulation of chr operon present in TnOtChr, which is controlled by a transcriptional regulator, ChrB, was characterized in the current work. Fusions of ...