N°1 Chung Mu/N°1 Chon Stone

On 9 March 1995, the Chon Stone N°1, a cargo boat, collided with the Chung Mu N°1, a chemical tanker built in 1994 loaded with styrene monomer, in the access channel to Zhanjiang’s harbour (Southern China).

When the ships collided, 208 tonnes of styrene monomer were spilled at sea. The breach was immediately sealed by divers with wooden plugs, however it is likely that some styrene continued to leak out gradually.

When immediate human health risks had been eliminated (styrene vapours are neurotoxic),the risks concerning the sea environment could be characterized by a change in the organoleptic characteristics of the flesh of fish and shellfish. Short styrene monomers are moderately toxic for aquatic life and bio-accumulate only to a small extent in the environment.

The Chung Mu was immobilized by the authorities and was ordered to provide a significant bank guarantee because of the potential damage to aquatic species. The insurance club contracted Cedre for two missions in China, in order to assess the damage the living resources had undergone. This estimation allowed the insurance club to come to an agreement with the authorities on a reasonable down payment and the release of the ship.