abstract chromium is among the metals that has numerous applications in various industries due to its specifications. widespread use of this metal in different industries has unfortunately been accompanied by its increased release into environment and this entails numerous environmental hazards. in the first phase of the research that was conducted to evaluate the effect of the leather processi...

The panel opened with a request to J. LaVelle (U.S. EPA) to enlarge upon his presentation of a bimodlal disposition for the plasma reduction of hexavalent chromium (and subsequent urine concentration) in an occupational group exposed to chromium. He replie(d that he did not know the size of the population that was exposed, but that the group consisted of workers at a dichromate plant, and the s...

phytoremediation of heavy metals is employed as a technological approach for a non-destructive remediation of contaminated soils. one of the most recently studied tree species used in phytoremediation applications are poplars. in this study, the one-year old rooted seedlings of populus nigra l. used to decontaminate hexavalent chromium-contaminated soils. five treatments of cr (vi) supply (were...

the objective of this work focuses on the use of a new natural lignocellulosic material based on palm stems for adsorbing of hexavalent chromium (cr(vi)) in water. the palm stems powder (psp) was characterized using different techniques. the influencing factors on the adsorption of cr(vi) ions was investigated such as ph. the results show that the increase of the temperature and the initial ads...

Calcium polysulfide (CPS) has been observed to maintain a reducing capacity for prolonged time periods when used to treat Cr(VI)-contaminated soils. This study utilized bulk and micro-X-ray absorption near edge structure (XANES) spectroscopy to investigate sulfur speciation in soil samples treated with CPS in batch and column studies and to determine the source of the reducing potential. Bulk X...

To update estimates of the prevalence of occupational exposures to carcinogens in Italy, the 85 CAREX agents were re-assessed. The original exposure estimates in the CAREX database were updated, taking into account changes in exposure patterns and in numbers of employees by industrial class. The 21.8 million employees in Italy, 19.4 in industry and services, 2.4 in agriculture, had 4.2 million ...

Spherical black carbon aggregates were frequently observed in dust dry deposition in Daejeon, Korea. They were tens of micrometers in diameter and presented a mixture of black carbon and several mineral phases. Transmission electron microscopy (TEM) observations with energy-dispersive X-ray spectroscopy (EDS) and selected area diffraction pattern (SADP) analyses confirmed that the aggregates we...

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.

Plasmids determining resistance to arsenic, mercury, silver, and tellurium compounds in Escherichia coli and Pseudomonas aeruginosa were tested for resistance to 40 other metal compounds. Resistance to trivalent boron and hexavalent chromium compounds was a property of certain P. aeruginosa plasmids.