High Quality Content by WIKIPEDIA articles! Arsenic biochemistry refers to biochemical processes that can use arsenic or its compounds, such as arsenate. Arsenic is a moderately abundant element on the earth`s crust, and although many arsenic compounds are often considered highly toxic, a wide variety of organoarsenic compounds are produced biologically and various organic and inorganic arsenic compounds are metabolized by numerous organisms. This pattern is general for other related elements, including selenium, which can exhibit both beneficial and deleterious effects. Arsenic biochemistry has become topical since many arsenic compounds are highly toxic and it is found in some aquifers, potentially affecting many millions of people via processes that are intrinsically biochemical.