PROBLEM TO BE SOLVED: To provide a treatment method for sufficiently exerting an elution reducing action on a pollutant containing toxic substances such as cationic and anionic heavy metals, maintaining pH of an eluate after treatment without respect to the pH atmosphere of the pollutant, and sufficiently exerting the elution reducing action on amphoteric metals. SOLUTION: The toxic substance elution reducing material contains ferrous chloride and magnesium oxide. For 100 pts.mass of the ferrous chloride, 50-200 pts.mass of the magnesium oxide is blended. COPYRIGHT: (C)2010,JPO&INPIT