Another year, another cadmium spill

Guest post by Xu Nan

He Xinxing, the mayor of Hechi City, in the south-west Chinese province of Guangxi, issued a public apology on February 1 for a cadmium spill two weeks ago in the Long River, which sparked great public concern.  Around 20 tonnes of cadmium leaked into the river: at the peak of the disaster the polluted body of water contained concentrations of cadmium 80 times higher than the level officially deemed safe, and a 300 kilometre section of the river has been affected. 

After emergency measures were implemented, the cadmium pollution’s peak concentration dropped to 25 times the safe level.  Two companies suspected of being responsible are a lithopone plant and a mining company.  Eight people have already been detained, and police are looking for another four.

Feng Zhennian, press spokesman for the emergency response centre set up to tackle the incident on the river, said that the situation was under control; that it was possible to contain most of the pollution to the Long River; and that he was confident the delivery of safe water to Liuzhou could be guaranteed.

Professor Zhang Xiaojian, from Tsinghua University’s Department of Environmental Sciences and Engineering , said in an interview with China News that it will take around one month to clean up the spill. 

He expressed his discontent with the current industrial conditions in Hechi City, which have caused the pollution: “Smelting must be conducted in the proper way.  If companies don’t properly consider how to extract the waste residue from the smelting process – if they simply take out the useful metals and discharge the heavy metal waste – pollution will result, if not now then in the future.” 

There have been several serious incidents of cadmium pollution in China over the last few years: the 2005 incident in Guangdong, where cadmium levels in the Shaoguan section of the Beijiang River dangerously exceeded allowable limits; the 2006 cadmium spill in the Zhuzhou section of the Xiang River in Hunan; and the 2009 cadmium pollution incident in Liuyang city, Hunan, among others.   Instances of “elevated blood lead levels” have occurred in Shaanxi, Anhui, Henan, Hunan, Fujian, Guangdong, Sichuan, Jiangsu, Shandong and other provinces. 

The Ministry of Environmental Protection said that in 2009, heavy metal pollution caused 4035 people to suffer excessive blood lead levels and 182 to suffer excessive cadmium levels, and that concerns over the pollution triggered 32 “mass incidents” of unrest.

The deputy director of the Ministry of Environmental Protection’s China National Environmental Monitoring Center, Wen Xiangcai, told the media that among China’s cases of heavy metal pollution, the most serious cases are associated with cadmium, mercury, blood lead and arsenic.

In China, heavy metal pollution varies locally, with the east typically more affected than the west, and the south more seriously affected than the north. The Pearl River Delta is another hotspot.  In addition, provinces such as Hunan, important for non-ferrous metals, are also critical areas of heavy metal pollution.  The river suffering China’s most serious heavy metal pollution is the Xiang.

Translated by Charlotte Foster