Three patients affected by poisonous mustard gas from chemical weapons abandoned by Japanese troops during World War II were discharged from hospital yesterday in Qiqihar in northeast China's Heilongjiang Province.

The released patients are Chen Ziwei, a 10-year-old girl; 28-year-old Li Changsheng from Anhui Province; and 19-year-old Gao Zhanyi, a Heilongjiang resident.

Despite their clean bill of health after two weeks' treatment, the victims could still suffer a recurrence of their symptoms, according to Sun Jinghai, director of No.203 Hospital of the People's Liberation Army.

Another 40 gas-affected patients are still in hospital, including six in critical condition, hospital sources said.

Doctors said the six critical patients have been affected by a decline in white blood cells, subdued blood production capability in marrow and respiratory problems.

The chemical weapons, discovered on August 4 at a construction site in Qiqihar, were stored in five metallic barrels, one of which was carelessly broken by the workers. When the barrel was broken, an oil-like substance oozed into the soil.

Things were made worse when the polluted soil from the construction site was removed by trucks to several different locations.

To solve the problem, Chinese and Japanese specialists have sealed the five barrels of mustard gas and finished treatment of the contaminated soil.

The barrels and contaminated soil are being stored in a place with around-the-clock security, Foreign Ministry sources told China Daily yesterday.

In addition to six Japanese experts on toxic storage who came to China earlier this month, another group of seven Japanese medical experts flew to Qiqihar to assist local doctors in treating the victims.

A Sino-Japanese joint medical panel held group consultations in the army hospital over the past several days. The Japanese experts left China yesterday.

Military experts said that China believes more than 2 million gas bombs were left in China by the Japanese troops, posing great risk to the Chinese people.

Gas bombs have been discovered in more than 10 provinces including Liaoning, Jilin, Heilongjiang in the northeast and Hubei and Hunan in central China.

The Japanese have admitted to leaving about 700,000 gas bombs in China, most littered in rivers and lakes, buried underground and stored in warehouses with other ordinary weapons. But they have refused to provide detailed information on the location of the chemical weapons.

First used by the German Army in World War I in 1917, mustard gas is one of the most lethal poisonous chemicals. It is almost odorless and takes 12 hours to take effect.

The skin of mustard gas victims blisters, the eyes become very sore and they start to vomit. Mustard gas also causes internal and external bleeding and attacks the bronchial tubes, stripping off the mucous membrane.

(China Daily August 19, 2003)