introduction: in electroplating processes, hexavalent chromium mist is emitted in air. hexavalent chromium mist can cause lung cancer and nasal septum in workers. as permissible exposure limit (pel) of hexavalent chromium is low (0.5 µg/m 3 ) and it is used in various industries, evaluation of workers exposure to hexavalent chromium is very important. however, hexavalent chromium is relatively ...

Background: The presence of heavy metals in the environment especially in water supplies have caused many concerns because of their toxicity and non-degradability. Hexavalent Chromium (Cr) is one of the most toxic metals which is used in many industries, so it is essential to remove it from industrial wastewater. In this study, we made a comparison between different adsorption isotherms in the ...

The kinetics of reduction and oxidation of soluble chromium in various soils (peat, clay, sand, and luvi-chromic cambisols) were studied at constant soil moisture and constant temperature. A total of 1500 g of each soil was incubated with different concentrations of aqueous solutions of K2Cr2O7 or CrCl3 [1-1000 μg (g of dry soil)-1]. The total exchangeable chromium and Cr(VI) were analyzed in s...

Background The objective of this study is to suggest revised recognition standards for occupational disease due to chromium (VI) by reflecting recent domestic and international research works and considering domestic exposure status with respect to target organs, exposure period, and cumulative exposure dose in relation to the chromium (VI)-induced occupational disease compensation. Methods I...

Lysine and leucine auxotrophic, heterothallic (h+, h-) strains of Schizosaccharomyces pombe were used to obtain chromium (VI)-sensitive and -tolerant mutants by ultraviolet radiation-induced and nitrosoguanidine-induced mutagenesis. The minimal inhibitory concentrations of K2Cr2O7 on YEA media were 225 microM for the wild-type strain CW-6, 125 microM for the sensitive mutant CS-6.51 and 275 mic...

Nine bacterial colonies were screened for the Cr(VI) removal efficiency and out of these three bacterial strains Pseudomonas putida, Pseudomonas aeruginosa and Bacillus sp. were isolated from soil and used to remove Cr(VI) from aqueous solution. The effect of time and concentrations on the removal rate of hexavalent chromium were studied using batch experiment. Maximum Cr (VI) removal was noted...

presence of heavy metals in the aquatic systems has become a serious problem. as a result, therehas been a great deal of attention given to new technologies for removal of heavy metal ions from contaminated waters. adsorption is one of the effective methods for removal of toxic heavy metal such as chromium (vi). in the present study, adsorbent is prepared from rice husk, a low cost by product f...

presence of heavy metals in the aquatic systems has become a serious problem. as a result, therehas been a great deal of attention given to new technologies for removal of heavy metal ions from contaminated waters. adsorption is one of the effective methods for removal of toxic heavy metal such as chromium (vi). in the present study, adsorbent is prepared from rice husk, a low cost by product f...

A new time-based flow injection on-line solid phase extraction method for chromium(VI) and lead determination using flame atomic absorption spectrometry was developed. The use of hydrophobic poly-chlorotrifluoroethylene (PCTFE)-beads as absorbent in on-line preconcentration system was evaluated. Effective formation of ammonium pyrrolidine dithiocarbamate complexes and subsequently retention in ...