background and aims: chromium is considered as one of the important environmental pollutants. there is high concentration of chromium in the wastewater of electroplating industries. magnetic iron nanoparticles are used to control and eliminate heavy metals from industrial effluents through the mechanisms of adsorption, ion exchange and electro-static forces. the aim of this study was to evaluat...

Hexavalent chromium is an established carcinogenic agent, which is not directly reactive with DNA. Its genotoxicity involves a reduction step, producing reactive oxygen species and radicals, and also lower valence forms which form stable complexes with intracellular macromolecules. The trivalent form of chromium may directly react with the genetic material and has also been shown to generate ox...

rinking water utilities face the challenge of addressing emerging water quality concerns to ensure adequate protection of public health, sometimes without final federal or state drinking water regulations. Total chromium, i.e., trivalent chromium [Cr(III)] plus hexavalent chromium [Cr(VI)], has been regulated by national drinking water regulations since 1975. The federal regulatory maximum cont...

Activated carbon was prepared from agricultural waste “almond (Prunus amygdalus) nut shells” by chemical activation with phosphoric acid as an activating agent at 450 C for 24 hr soaking time. The physical and chemical properties were analyzed. The adsorption of chromium VI from aqueous solution on almond nut shell activated carbon (ASAC) was investigated. The adsorption process parameters pH, ...

Arachis hypogea shells (ground nut shells), a lignocellulosic waste biomass, was evaluated for sequestering of Cr(VI) from synthetic wastewater. Arachis hypogea shells (AHS) were used in three different forms, viz.natural (AHSN), immobilized in the form of beads (AHSB), and in the form of activated carbon (AHSC). Batch experiments were performed for the removal of hexavalent chromium. Effects o...

The objective of this paper is to demonstrate an approach to characterize the spatial variability in ambient air concentrations using mobile platform measurements. This approach may be useful for air toxics assessments in Environmental Justice applications, epidemiological studies, and environmental health risk assessments. In this study, we developed and applied a method to characterize air to...

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...

Washed cells of Enterobacter cloacae HO1 reduced hexavalent chromium (chromate: CrO4(2-) anaerobically. Chromate reductase activity was preferentially associated with the membrane fraction of the cells. Right-side-out membrane vesicles prepared from E. cloacae cells showed high chromate reductase activities when ascorbate-reduced phenazine methosulfate was added as an electron donor.