One of the actual global problems is an issue of waste, its formation, disposal and possible secondary processing. Another closely related issue concerns hazardous waste which represents a potential threat to environment and human health. This paper is focused on an area of waste containing hexavalent chromium arising especially from leather industry. Hexavalent chromium is classified as a carc...

Chromium is present in the environment in several different forms. The most common forms are chromium(0), chromium(III) (or trivalent chromium) and chromium(VI) (or hexavalent chromium). Chromium(III) occurs naturally in the environment and is an essential nutrient that helps the human body utilize sugar, protein and fat. Chromium(VI) and chromium(0) are generally produced by industrial process...

absorptive characteristics of polyaniline synthesized with two different oxidants including potassium iodate and ammonium persulfate was studied. synthesized polyanilines in powder shape is used as an adsorbent to remove toxic hexavalent chromium from aqueous solutions. experiments were conducted in batch mode with different variables such as agitation time, solution ph and initial concentratio...

Chromium (vi) – tolerant bacterial strains, namely, Bacillus sp., Pseudomonas sp., Escherichia coli and Staphylococcus sp. were isolated from the oxidation ditch of a sewage treatment plant. All the isolates tolerated high concentrations of up to 500 μg/ml chromium (vi) in nutrient broth. The growth responses of the bacterial isolates to different concentrations of chromium (vi) were carried ou...

Hexavalent chromium is an environmental contaminant. Within the environment, marine waters are a common site for hexavalent chromium deposition. We have recently reported significantly high levels of chromium in skin tissue from North Atlantic right whales. These findings demonstrate that marine species are being exposed to chromium. It is possible that such exposures may be playing a role in p...

Annually, a large amount of effluents is discharged from an industrial zone dedicated to leather industries into a dried seasonal waterway bed in Mashhad plain, Northeast of Iran. These soils are high in pH, CaCO contents and have no naturally occurring chromium detectable in mg/kg range. Considering high 3 concentration of chromium in the discharged leather industries effluents and their direc...

MATERIALS AND METHODS Chromium is known to be an essential element1. Epidemiological and experimental studies have, however, demonstrated that some chromium compouds (mainly hexavalent salts) are mutagenic carcinogens2-5) (see ref. 1 for review). Recent studies have also shown that the hexavalent compounds induce dose-related increases in chromosomal aberrations and sister chromatid exchanges i...

Estimation of water soluble hexavalent chromium and total chromium has been devised. For the complete extraction of water soluble hexavalent chromium, leaching period of five days is done. It was ascertained that complete extraction was achieved in five days; the total chromium determination in these samples was done by fusing sample with sodium carbonate up to 1050 C in muffle furnace. Chromiu...