About 25 percent of domestic production of ethylene, a key material for petrochemical products, has been halted following last week's earthquake, the head of the petrochemical industry body said Thursday.

"One-quarter of domestic manufacturing capacity of ethylene has stopped," said Kyohei Takahashi, chairman of the Japan Petrochemical Industry Association.

Plastic bottles and medical containers, which are needed in the earthquake-hit area, are made of ethylene.

Takahashi, also chairman of Showa Denko K.K., suggested the halt in production will affect a wide range of industries. Mitsubishi Chemical Corp. has been forced to halt operations at its ethylene plant in Ibaraki Prefecture.