China's troubles with air and water pollution are widely known with its smog-clouded cities and chemical-filled rivers drawing international attention. However, there is another, less visible consequence of the whirlwind GDP growth the country has experienced over the past three decades: soil pollution.

"Rapid industrialization has left a legacy of soil pollution that is damaging health and livelihoods in villages across China," concluded a recent investigation titled "The victims of China's soil pollution crisis," jointly conducted by Yale Environment 360 and chinadialogue, a non-profit organization based in London and Beijing.

However, soil pollution is not only affecting the health and well-being of Chinese citizens, it is also putting the nation's food security at risk. A Chinese government report released in April this year said that 16.1 percent of the country's soil was polluted.

The figure for contaminated farmland is even higher, 19.4 percent. The main contaminants are heavy metals such as cadmium, lead, nickel and arsenic, among others.

19.4 percent of the farmland in China is contaminated, according to the government

The areas mainly affected include the country's industrial belt along the eastern coast as well as inland provinces in central and western China. Experts say the main sources of this kind of pollution are industrial waste seeping from factories onto the soil, and agricultural activities such as the application of fertilizers and the use of polluted water for irrigation. The level of pollution has raised questions about the quality of food produced in the contaminated regions.

Serious health risks

Miao Zhang, senior toxic campaigner at Greenpeace East Asia, explains that soil pollution can cause underground water contamination, thus damaging the quality and quantity of crops. The contaminants, in turn, tend to "accumulate in the human body through food chain," Miao told DW.

But despite the awareness of what pollution can do, poor people have little choice but to eat locally produced food, highlights the chinadialogue report. The organization's founder and editor, Isabel Hilton, said in a DW interview that serious health issues, including cancer and diseases infecting the nervous system, could be caused by soil pollution.

"Like many conditions with environmental causes, the exact chain of consequence in any case is hard to establish. But statistical and epidemiological evidence makes a strong case for the relationship between pollution and ill-health," she pointed out.

Soil pollution in China has attracted little public attention, in spite of the health threats. Until recently, the government also resisted media attempts to spotlight local cancer epidemics in the country's newly industrial areas, the report claims. Indeed, the Chinese government previously refused to divulge information on soil pollution terming it a "state secret."

A severe problem

But in February 2013, the Ministry of Environmental Protection (MEP) finally admitted that "cancer villages" existed in China. The chinadialogue report cites the estimates of some civil society groups which put the number of such villages at around 450, and that the figure is on the rise.

Describing the pollution problem as "severe and urgent," Greenpeace's Miao says that it is hard to understand the reasons behind the government's reluctance to share information. "But hiding the data did make people wonder whether it was because the problem was too terrible to be known," she added.

Analysts, however, agree that Beijing has started taking measures to confront the problem, although it still has a long way to go. "Many polluting factories have been shut down in central and eastern parts of the country. Unfortunately, this is less true of western China where there are thousands of toxic sites that need to be contained and we are still not seeing the necessary level of pollution control," explained Hilton.

Furthermore, experts call for more government focus on crop safety, demanding that contaminated sites should be taken out of food production chain. But getting rid of the pollution is not only about the removal of contaminants, it also involves the restoration of soil health, which is required to ensure food safety and people's health. The need of the hour is a reorientation of the Chinese development model, which has succeeded in lifting millions of people out of poverty over the last three decades.

Hidden costs

The problem is that the emphasis was on very rapid growth and little attention was paid to the negative effects, which economists call externalities, stressed Hilton. "These effects are showing up in health impacts, food safety, food security and water scarcity as well as contamination.

Air and water pollution in China have drawn more international attention than soil contamination

All of these have economic impacts, so looking only at GDP growth does not give you the true picture," the expert underlined.

This view is shared by Greenpeace campaigner Miao, who argues that treating one million hectares of polluted soil will cost at least 140 billion yuan (22.6 billion USD). "The economic development in the past 30 years did make China a good fortune. However, there is already evidence showing that there is huge debt behind the prosperity."