this study was performed to explore the presence of heavy metals in some popular herbal medicines of the iranian market. primarily, this study was planned to do the task by the usp method. in the second step, those plants which contained more than 10 ppm of total heavy metals were analyzed by atomic absorption method. in this study, 43 popular herbal medicines were investigated according to the...

background: due to the increasing pollution of water resources, this study was carried out for evaluation of water quality pollution indices for monitoring of heavy metals (as, zn, pb and cu) contamination in ghahavand plain, hamadan province, western iran during spring and summer 2012. methods: totally, 20 ground water wells were chosen randomly. the samples were filtered (0.45 μm) and maintai...

1. Basic Concepts 1.1. Air Pollution 1.2. Criteria and Non-Criteria 1.3. Emissions 2. The Epidemiological Model 3. Toxic Trace Elements from Fossil Fuel Combustion 4. Environmental Behavior of Metal Pollutants 4.1. Atmospheric Aerosol Particles 4.2. Aqueous and Marine Environments 4.3. Accumulation of Heavy Metals in Marine Invertebrates 4.4. Heavy Metal ions in Soils 4.5. Methylation of Heavy ...

Contamination of soils, water, and sediments by radionuclides and toxic metals from uranium mill tailings, nuclear fuel manufacturing and nuclear weapons production is a major concern. Studies of the mechanisms of biotransformation of uranium and toxic metals under various microbial process conditions has resulted in the development of two treatment processes: (i) stabilization of uranium and t...

Urban soil pollution has become a major concern in megacities around the world. Due to their non-degradable characteristic, toxic metals are among the most notorious pollutants. In this study determination of total and bioavailable fraction of toxic metals Ni, Cu, Cr, Zn, Co, Cd, Pb and Mn, in surface soils of district 16th in Tehran municipality is considered. Furthermore, metals uptake potent...

Environmental toxicants such as toxic metals can alter epigenetic regulatory features such as DNA methylation, histone modification, and non-coding RNA expression. Heavy metals influence gene expression by epigenetic mechanisms and by directly binding to various metal response elements in the target gene promoters. Given the role of epigenetic alterations in regulating genes, there is potential...

Urban soil pollution has become a major concern in megacities around the world. Due to their non-degradable characteristic, toxic metals are among the most notorious pollutants. In this study determination of total and bioavailable fraction of toxic metals Ni, Cu, Cr, Zn, Co, Cd, Pb and Mn, in surface soils of district 16th in Tehran municipality is considered. Furthermore, metals uptake potent...

background: milk is regarded as a unique source of food for all ages. when milk is exposed to various contaminants, including lead and cadmium, it is considered a risk to humans. the presence of some metal pollutants, especially cd and pb, facilitates their entry into the food chain and thus increases the possibility of their toxic effects on humans and animals. therefore, we decided to check l...

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...

Aminopolycarboxylate chelants (APCs) are extremely useful for a variety of industrial applications, including the treatment of toxic metal-contaminated solid waste materials. Because non-toxic matrix elements compete with toxic metals for the binding sites of APCs, an excess of chelant is commonly added to ensure the adequate sequestration of toxic metal contaminants during waste treatment oper...