In order to render sewage sludge suitable for beneficial purposes, it must be disinfected and stabilized. EDC deactivation is rapidly becoming a desirable result of any sludge or biosolids treatment process. Disclosed herein is a process of treating sewage sludge so as to stabilize the sludge that involves the presence of an iron-containing compound during dewatering of the sludge. Process embodiments described also achieve biosolid samples that have reduced EDC activity, Other embodiments disclosed involve use of a combination of iron salts ferrate and ferric chloride that are added to wastewater sludge in the dewatering step before heat drying. The biosolids resulting from sludge treated with aniron-containing compound are able to resist putrefaction for more than two to three weeks.