Two methods described in this paper use respirometric monitoring of the accumulated oxygen uptake rate, following the addition of bleachery effluents to a reactor containing Penicillium camemberti and detection of inorganic chloride removal by a chloride electrode for electron acceptor identification. In the case of respirometric studies, adsorbable organic halogens (AOX) removal was retarded at high acetate concentrations and the metabolism shifted towards aerobic respiration. Contrary to this, aerobic respiration was suppressed at low acetate concentrations and the removal of AOX was enhanced. Inorganic chloride removal detected with a chloride electrode verified these findings too. Cl- ion production paralleling AOX removal supports the hypothesis that organic chlorine acts as electron acceptor for this fungus.