Assessment of di-(2-ethylhexyl) phthalate (DEHP) in municipal and industrial sludges of taiwan by supercritical fluid extraction (SFE) and gas chromatography with electron ionization detection

Abstract

In the present study, DEHP in selected municipal sewage (raw and treated) and industrial sludges of Taiwan was quantified by SFE and GC/EID. As a precursor, the optimal operating parameters of SFE were identified by laboratory experiments using DEHP spiked quartz sand. DEHP extraction efficiency was increased by the addition of modifier i.e. methanol (0.5mL, 7%). DEHP concentration in all sewage sludge (M-1 to M-4) and a textile industry (I-6) samples were above the limit suggested by the European Union (100 mg/kg). The results suggest that excess DEHP concentration observed in the sewage sludge needs considerable attention before disposal.