background: the removal of toxic metals from sewage and wastewaters is one of the most important concerns in the twenty first century. the removal of poisonous cr(vi) from aqueous solution by different low-cost available nanoporous adsorbents was investigated in the present study.  methods: fumed silica, bentonite (bn), hydrotalcite (ht), mcm-41, na-y, mordenite (mor) and sapo-34 were used at d...

background: welding can produce dangerous fumes containing various metals especially carcinogenic ones. occupational exposure to welding fumes is associated with lung cancer. therefore, welders in gas transmission pipelines are known as a high-risk group. this study was designed to determinate the amounts of metals cr, ni, and cd in breathing zone and urine of welders and to assess the possibil...

absorptive characteristics of polyaniline synthesized in different solvents were studied. water and mixture of water with other solvents were implemented for polyaniline synthesis. synthesized polyanilines in powder shape is used as an adsorbent to remove toxic hexavalent chromium from aqueous solutions. experiments were conducted in batch mode. removal mechanism involving polyaniline is the co...

in the process of vermicomposting, the earthworms eisenia fetida have been exposed to various metals with different concentrations to study the effects on worms’ bioaccumulation. the study was carried within 14 days of exposure. five different chemical compounds in various concentrations were added as mixture solutions to the experimental containers. metals concentrations were measured in earth...

introduction: recent investigations have detected the presence of significant levels of heavy metals (chromium, lead and cadmium) in toys and other pvc products manufactured for children. in some countries, addition of compounds containing toxic metals to toys are limited or prohibited. methods: to evaluate the safety of some of the plastic toys in the city of isfahan with respect to toxic trac...