3.3 million hectares of China’s farmland too polluted to grow food, says official

A farmer in China's Jiangxi province plows a terrace farm.China's pollution woes have been in the news fairly often lately, with reports of post-apocalyptic levels of smog and water quality so bad that locals won't even trust the bottled water. However, the latest news from China's government raises even more concerns, as millions of hectares of the country's farmland has been found to be far too polluted to safely grow crops.

This new information was presented at a news conference on Monday by Wang Shiyuan, a deputy minister of China's Ministry of Land and Resources. It was taken from a 2006-2009 soil survey published earlier this year, but kept out of the public eye as a state secret until now.

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According to Shanghai Daily, Wang said that around 3.33 million hectares — which is roughly 2.5 per cent of China's more than 135 million hectares of arable farmland — was identified as being too badly contaminated by heavy metals and chemicals to be used for farming. However, according to the Associated Press, some scientists have said the contaminated area could be much larger, closer to 24 million hectares.

Wang said in the news conference that much of this polluted land is located in developed regions of eastern and central China, "such as the Yangtze River Delta, the Pearl River Delta, the old industrial base in northeast China and central China’s Hunan Province."

One of the main concerns comes from the heavy metal cadmium, which is naturally-occurring, but gets concentrated in the environment from sources like smelting and industrial waste. Cadmium that gets into the water and soil is readily absorbed by plants and can end up in our food supply. When cadmium-contaminated food or water is consumed, high levels can cause vomiting and diarrhea, and in some cases can lead to death. Low levels collect in the liver and kidneys and can remain there for a very long time. This can possibly result in kidney damage. Cadmium has also been identified as a human carcinogen.

High levels of cadmium, in excess of China's environmental standards, were found in rice being sold in Guangzhou, northeast of Hong Kong, from samples taken from restaurants and canteens in January, February and March of this year. According to the Guangzhou Food and Drug Administration, eight of the 18 samples taken during that time tested higher than the standard.

As a result of these findings, all farming in the contaminated areas has apparently been stopped, and according to China Daily, the government plans on rehabilitating the land.

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Food production is a major concern for China, since its 135 million hectares of farmland is only 15 million hectares above what the government considers to be enough to provide food security. According to what Wang said in the news conference, the amount of farmland will be reduced to 120 million hectares — right at the government's food-security limit — since some land will be converting over to grasslands, wetlands and forests, using plants that are known to reduce pollution levels in soil. Some land will remain unusable for farming due to the pollution.

(Photo courtesy: Reuters)

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