Impact of an external electron acceptor on phosphorus mobility between water and sediments

•The present study assess the impact of an external electron acceptor on P fluxes.•Both SMFC tested were able to produce electricity.•SMFC operation increased metal bound P, Ca-bound P, and refractory P fractions.•The results indicate an important role of electroactive bacteria in the P cycling.•This study opens a new perspective for preventing P dissolution from sediments. The present work assessed the impact of an external electron acceptor on phosphorus fluxes between water and sediment interface. Microcosm experiments simulating a sediment microbial fuel cell (SMFC) were carried out and phosphorus was extracted by an optimized combination of three methods. Despite the low voltage recorded, ∼96mV (SMFC with carbon paper anode) and ∼146mV (SMFC with stainless steel scourer anode), corresponding to a power density of 1.15 and 0.13mW/m2, it was enough to produce an increase in the amounts of metal bound phosphorus (14% vs 11%), Ca-bound phosphorus (26% vs 23%), and refractory phosphorus (33% vs 28%). These results indicate an important role of electroactive bacteria in the phosphorus cycling and open a new perspective for preventing metal bound phosphorus dissolution from sediments.