Tianjin, a port city some 120 kilometers from the nation's capital Beijing, is clearing its market of substandard stone building materials to minimize emission of radioactive substances.

Starting from Thursday, the Tianjin Municipal Environmental Protection Bureau has started a thorough checkup of the market and would punish manufacturers and dealers of furnishing materials with excess radiation.

"They could be fined or have their business licenses suspended, and would be held responsible for damages to the consumers' health," said a source with the industrial watchdog.

The move was in line with the country's newly enacted law on the prevention of radioactive pollution, which came into effect on October 1.

Stone building materials are used by many Chinese urban families to tile floors and walls, but those of poor quality could give off radon, a radioactive gas that could impair the respiratory system and even cause lung cancer, experts say.

Other radioactive substances from substandard stones could also endanger human health by damaging the blood-generating, reproductive, digestive and neural systems.

Indoor air pollution has been listed one of the top 10 threats to human health. Unqualified household furnishing materials are a main source of poisonous substances.

In China alone, the pollution causes a reported annual death toll of 111,000 people.

(People's Daily December 8, 2003)