CHENJIAWAN, China – In many villages like this one in China’s agricultural heartland, fields where produce is grown are ringed by factories and irrigated with water tainted by industrial waste. Levels of toxic heavy metals in the wastewater here are among the highest in China, and residents fear the soil is similarly contaminated. Though they have no scientific proof, they suspect that a spate of cancer deaths is linked to the pollution, and they worry about levels of lead in the children’s blood.

“Of course, I’m afraid,” said Ge Songqing, who is in her 60s. She pointed to the smokestacks looming over her fields and the stagnant, algae-filled irrigation canals surrounding a home she shares with a granddaughter and her husband, a former soldier. “But we don’t do physical checkups. If we find out we have cancer, it’s only a burden on the children.”

With awareness rising of China’s severe environmental degradation, ordinary Chinese people and some officials during the last year have expressed anxiety about soil pollution in the country’s agricultural centers and resulting effects on the food chain. In recent years, the government has conducted widespread testing of soil across China, but it has declined to release the results, exacerbating the fear and making it more difficult for ordinary Chinese to judge what they eat and pinpoint the offending factories.

On Monday, a vice minister of land and resources, Wang Shiyuan, said at a news conference in Beijing that 8 million acres of China’s farmland, equal to the size of Maryland, had become so polluted that planting crops on it “should not be allowed.”

In May, officials in Guangdong province, in the far south, said they had discovered excessive levels of cadmium in 155 batches of rice collected from markets, restaurants and storehouses. Of those, 89 were from Hunan province, where Ge farms. In June, China Daily, an official, English-language newspaper, published an editorial saying that “soil contaminated with heavy metals is eroding the foundation of the country’s food safety and becoming a looming public health hazard.”

One-sixth of China’s arable land – nearly 50 million acres – suffers from soil pollution, according to Soil Pollution and Physical Health, a book published this year by China’s Ministry of Environmental Protection. The book said that more than 13 million tons of crops harvested each year were contaminated with heavy metals, and 22 million acres of farmland were affected by pesticides.