The health ministry will ban creosote oil for home use because it contains carcinogens, ministry sources said Wednesday.

Many Japanese use garden equipment made from old wooden railroad ties that contain creosote oil. The oil, used as a preservative, contains the carcinogen benzopyrene.

The Health, Labor and Welfare Ministry plans to add the oil to the household goods regulation law. It would be the first time a new substance is added to the law in 20 years, the sources said.

A health ministry panel discussing safety measures for household goods determined that the maximum level of the oil must be less than 10 parts per million, the sources said. The level will officially be set this autumn, they said.

Gardening equipment using old wooden railroad ties have become increasingly popular, prompting a health ministry group to analyze the components of the tools in fiscal 2002, they said.

The law on banned materials took effect in 1974. It specifies 16 toxic substances, including formaldehyde and trichloroethylene.