The present study was carried out close to a fish farming area in the Gulf of Castellammare (N-W Sicily) in summer 2004. Specimens of Mytilus galloprovincialis were transplanted in putatively impacted areas and controls to test the recycler capability of bivalves for reducing the impact of waste on the surrounding environment.Mussels cultivated close to farms grew quicker than mussels in controls transforming waste OM in edible biomass and those positioned at 3 meters depth reached higher levels of secondary production than those at 9 meters.