The pollution of the sea around the Giglio cruise liner wreck "has already begun", Franco Gabrielli, the head of Italy's civil protection agency, said last night.
He said pollutants, including cooking oils, detergents and chlorine, had been detected near the ship. The big fear is that the Costa Concordia's fuel tanks could rupture and spill 2,380 tonnes of toxic fuel oil into what is an important fishing area and marine nature reserve.
Oil-removal equipment has been standing by, waiting for the search-and-rescue operations to conclude before workers can start extracting the fuel.
But yesterday, choppy seas kept divers from exploring the submerged part, where officials have said there could be bodies, including those of clandestine passengers not listed on the ship's log.