Aminomethylphosphonic acid (AMPA) is a weak organic acid with a phosphonic acid group. It is one of the primary degradation products of the herbicide glyphosate.[1] AMPA has low toxicity which is comparable to that of glyphosate and it is therefore considered to be of no greater toxicological concern than glyphosate itself.[2] AMPA has been shown to be broken down further by manganese oxide which occurs naturally in soil,[3] or to phosphoric acid via bacterial action [4][5] and ultimately to carbon dioxide and inorganic phosphate.[6]