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The main factors are pH and the redox potential. Generally, the main forms of arsenic under oxic conditions are H 3 AsO 4, H 2 AsO − 4, HAsO 2− 4, and AsO 3− 4 at pH 2, 2–7, 7–11 and 11, respectively. Under reducing conditions, H 3 AsO 4 is predominant at pH 2–9. Oxidation and reduction affects the migration of arsenic in subsurface ...
In its standard state arsine is a colorless, denser-than-air gas that is slightly soluble in water (2% at 20 °C) [1] and in many organic solvents as well. [citation needed] Arsine itself is odorless, [5] but it oxidizes in air and this creates a slight garlic or fish-like scent when the compound is present above 0.5 ppm. [6]
Under normal conditions the Nrf2 is bound to Kelch-like ECH associated protein 1 in its inactive form. [33] With the uptake of arsenic within cells and the subsequent reactions that result in the production of reactive oxygen species (ROS), the Nrf2 unbinds and becomes active.
Arsenic trioxide activates JNK (c-Jun N-terminal kinase), also known as stress-activated protein kinase, which belongs to the MAPK (mitogen-activated protein kinase) family. These enzymes play a crucial role in signal transduction within the cell. Under normal conditions, JNK is activated by the phosphorylation of threonine and tyrosine residues.
Arsenic trioxide powder.. Compounds of arsenic resemble in some respects those of phosphorus which occupies the same group (column) of the periodic table.The most common oxidation states for arsenic are: −3 in the arsenides, which are alloy-like intermetallic compounds, +3 in the arsenites, and +5 in the arsenates and most organoarsenic compounds.
Arsenic acid or arsoric acid is the chemical compound with the formula H 3 AsO 4. More descriptively written as AsO(OH) 3, this colorless acid is the arsenic analogue of phosphoric acid. Arsenate and phosphate salts behave very similarly. Arsenic acid as such has not been isolated, but is only found in solution, where it is largely ionized.
Under wet conditions, the mold Scopulariopsis brevicaulis produced significant amounts of methyl arsines via methylation [25] of arsenic-containing inorganic pigments, especially Paris green and Scheele's green. In these compounds, the arsenic is either pentavalent or trivalent (arsenic is in group 15), depending on the compound.
The arsenic (As) cycle is the biogeochemical cycle of natural and anthropogenic exchanges of arsenic terms through the atmosphere, lithosphere, pedosphere, hydrosphere, and biosphere. Although arsenic is naturally abundant in the Earth's crust, long-term exposure and high concentrations of arsenic can be detrimental to human health. [1] [2]