Risks from tanker leak lessening, say French

French officials watched helplessly yesterday as a sunken Italian tanker leaked a dangerous chemical into the Channel off the coast of Normandy. Technicians were unable to intervene, or even to assess fully the extent of the leak, for fear of provoking an explosion.

The French navy minesweeper Cephee, equipped with radar and an underwater robot, arrived in the area of the shipwreck early yesterday, 24 hours after the Ievoli Sun sank. Its crew wore protective clothing designed for chemical and biological warfare.

But the robot could not be lowered because of the swells. And it was judged too risky for the crew to take samples from the pools of foul-smelling, irridescent liquid floating on the surface. The liquid was assumed to be a mixture of diesel fuel and the inflammable, explosive chemical styrene.

Operations were suspended and all ships were warned to stay 6 km away.

Styrene accounted for two-thirds of the Ievoli Sun's 6,000tonne cargo. It is a fossil fuel and is the principal component of polystyrene plastic. Shell France, which owned it, has admitted that it "can be harmful to human health".

The chemical was carried in liquid form, and it releases intense heat - and sometimes explodes - when it solidifies into plastic.

French experts yesterday attempted to put an optimistic spin on the leak, saying that most of the toxic chemical would rise to the surface and evaporate.

In 1995, 200 tonnes of styrene - one-eighth the amount carried by the Ievoli Sun - were spilled in a Chinese port. Neighbouring areas were evacuated for 12 hours.

French officials may seek to briefly move the 2,100 residents of the British Channel Island of Alderney, 19 km from the shipwreck, if a poisonous cloud blows in its direction.

Experts say the greatest danger - that the Ievoli Sun could have exploded and killed the crew of the tug-boat which attempted to tow it to Cherbourg on Tuesday - has passed. But Channel fishing may suffer.

"Just a few parts per million [of styrene] make fish and shellfish inedible because of the taste, although they are not poisonous," said Dr Bruno Barnouin of the French sea exploration institute IFREMER.

Although the Ievoli Sun sank closer to Normandy than Britain, its proximity to the Channel Islands means it is technically in British waters. But the British Maritime and Coastguard Agency (MCA), quoted by Le Monde, said that since French interests were more at risk, it would let France take charge of anti-pollution efforts.

The MCA predicted that the styrene carried by the Ievoli Sun would solidify inside its tanks in 20 to 40 days.

The other chemicals transported by the Ievoli-Sun were isopropyl alcohol and methyl trichlorosilane belonging to Exxon Mobil. If they leak, they will dissolve in sea water and reportedly represent no danger to the environment other than inebriating fish near the wreck.

President Chirac beat his rival the Prime Minister, Mr Lionel Jospin, to Cherbourg yesterday. Mr Chirac said that "serious danger appears to have been avoided" but warned that "in these matters you cannot be too careful".