Biostabilization enhancement of heavy metals during the vermiremediation of sewage sludge with passivant

► Earthworms accumulated considerable levels of metals in their tissues. ► Higher BCFs occurred for treatments containing certain ratios of FA and PR. ► Pb, Cd and As biostabilization was improved by adding FA and PR in vermicomposting. ► The optimal enhancement of SS vermiremediation might be treatment at Trf. ► Total and extractable heavy metals changes might be predicable from their BCFs.