An evaluation of the chromium(VI) adsorption capacity of four magnetite sorbents coated with a polymer phase containing polymethacrylic acid or polyallyl-3-methylimidazolium is presented. Factors that influence the chromium(VI) removal such as solution pH and contact time were investigated in batch experiments and in stirred tank reactor mode. Affinity and rate constants increased with the mola...

Effects of water contamination with perchlorate and hexavalent chromium [Cr (VI)] on the mosquito Culex quinquefasciatus were assessed. The chronic (10-day) LC50s values for perchlorate and chromium were 74+/-8.0 mg/L and 0.41+/-0.15 mg/L, respectively. Relative Growth Index, a measure of growth and mortality rates in a population, was significantly reduced within 5 days for levels of perchlora...

The present study describes management of oxidative stress induced by heavy metal chromium in marine Bacillus licheniformis (NCBI GenBank Accession NumberHM194725). It is identified that the isolate reduces 10-1500 mg/L of Cr (VI) within 24-72 h. Existence of chromium reductase in growth medium implies the possibility of enzymatic reduction of Cr (VI) to Cr (III). Nevertheless, no correlation w...

EXTENDED ABSTRACT Hexavalent chromium [Cr(VI)] has long been recognized as a potential carcinogen, via the inhalation route while nowadays, there is an increasing concern that Cr(VI) is also carcinogenic by the oral route of exposure. According to this, governments apply more stringent regulations for chromium species. There are several discussions and intentions to lower the current maximum pe...

Carcinogenic heavy metal chromium, in its hexavalent form (Cr(VI)), is spuriously used in various industrial operations because of its hardness and stability and is found in industrial effluents in concentrations much above WHO’s prescribed limit (50 mg/L). Conventional methods for removing toxic chromium ion (by chemical reduction followed by precipitation, ionexchange and adsorption on activa...

Microbial reduction is a promising strategy for chromium remediation, but the effects of competing electron acceptors are still poorly understood. We investigated chromate (Cr(VI)) reduction in batch cultures of Shewanella oneidensis MR-1 under aerobic and denitrifying conditions and in the absence of an additional electron acceptor. Growth and Cr(VI) removal patterns suggested a cometabolic re...

This study deals with the enhancement of chromium (VI) removal by vacuum drying and plasma pre-treatments of cocolumber (Cocos nucifera) sawdust. For fixed adsorbent dose and pH, the effects of important parameters such as initial adsorbate concentration and contact time are determined. Results show that both pre-treatments increased the adsorption efficiency of the sawdust. The adsorption data...

The wastewater at Sukinda chromite mines (SCM) area of Orissa (India) showed high levels of toxic hexavalent chromium (Cr VI). Wastewater from chromium-contaminated mines exhibit potential threats for biotic community in the vicinity. The aim of the present investigation is to develop a suitable phytoremediation technology for the effective removal of toxic hexavalent chromium from mines wastew...

Hexavalent chromium (VI) compounds are widely used in industry, while trivalent chromium (III) is used as a nutritional supplement. CrVI is generally considered more toxic and carcinogenic than its trivalent form and the toxicity of this metal is associated with free radical processes generating reactive oxygen species (ROS). The detailed mechanism of ROS formation by chromium and its compounds...