The easy-biodegradation test, OECD 301B, was used to study the acid and its chelates formed with Fe(III), Cu(II), Zn(II), and Mn(III). Bacterial cultures were taken from surface waters and from a wastewater treatment plant and used as inoculum. The acid and the chelates biodegraded easily, 90% in 28 days on darkness (except for the Cu chelate whose Cu ions were toxic to the microorganisms used) as compared with conventional Fe chelates of etyhylenediaminetetraacetic acid, diethylenetetraaminepentaacetic acid, and ethylenediamine-N,N'-bis(2-hydroxyphenyl)acetic acid, which were resistant.