June 13, 2012
Don’t Eat The Broccoli In China
Michael Crumbliss for redOrbit.com
China has the worst pollution problems in the world. And it is getting worse as the utterly unchecked rush to industrialization continues. Much of this is pollution is linked to coal mining and power generation, but the sources of toxins are myriad.While air and water pollution are highly visible and overwhelming on an everyday basis, the worst long-term toxic buildup may be lurking quietly underfoot in the soil. Nowhere is the global push to restore degraded land likely to be more important, complex and expensive than in China, where vast swaths of the soil are contaminated by arsenic and heavy metals from mines and factories.
There are dire consequences for food production and human health. On top of having the highest cancer rate in the world China has the highest rate of birth defects. No one disputes that this is the result of pollution. It could be argued that the country is fast on the way to killing itself as it grows.
Literally at the root of this epidemic of poisoning is tainted soil that sends toxins and carcinogens to the dinner table, where people unknowingly eat them. Where does this lead? Will parents tell their children not to eat vegetables? It seems that perhaps they should.
Zhou Jianmin, director of the China Soil Association, estimated that one-tenth of China's farmland was affected. "The country, the government and the public should realize how serious the soil pollution is," he said. "More areas are being affected, the degree of contamination is intensifying and the range of toxins is increasing."
Other estimates of soil pollution range as high as 40%, but an official risk assessment is unlikely to be made public for several years.
Mining is largely to blame, though lead and heavy metals from factories and overuse of pesticides and fertilizers by farmers are also a factor.
Chen Tongbin of the Chinese Academy of Sciences said the worst contamination was in Yunnan, Sichuan, Hunan, Anhui and Guizhou, but there were also parts of Beijing where the soil is tainted.
Unlike in Europe where persistent organic pollutants are the main concern, Chen said China's worst soil contamination is from arsenic, which is released during the mining of copper, gold and other minerals. Roughly 70% of the world's arsenic is found in China — and it is increasingly coming to the surface with horrendous consequences.
"When pollution spills cause massive die-offs of fish, the media usually blames cadmium, but that's wrong. Arsenic is responsible. This is the most dangerous chemical," he said. The country's 280,000 mines are most responsible, according to Chen.
Chen estimated that "no more than 20% of China's soil is seriously polluted", but he warned that the problem was likely to grow because 80% of the pollutants in the air and water ended up in the earth.
"The biggest environmental challenge that China faces today is water pollution, but there are efforts underway to control that. In the future, the focus must be on soil pollution because that is much harder to deal with. Soil remediation is an immense and growing challenge."