Fig. 1From: Paradoxical effects of arsenic in the lungsArsenic metabolism pathway in the human body. 1. iAs (III) is methylated by arsenic-3-methyltransferase (AS3MT), using s-adenosylmethionine (SAM) as a methyl donor to form monomethylarsonic acid (MMAsV). 2. MMAV is reduced to monomethyl arsonous form (MMAsIII), which is then methylated by AS3MT to form dimethylarsinic acid (DMAsV)Back to article page