At Chen Qiang’s tilapia farm in Yangjiang city in China’s Guangdong province, which borders Hong Kong, Chen feeds fish partly with feces from hundreds of pigs and geese. That practice is dangerous for American consumers, says Michael Doyle, director of the University of Georgia’s Center for Food Safety.
“The manure the Chinese use to feed fish is frequently contaminated with microbes like salmonella,” says Doyle, who has studied foodborne diseases in China.
On a sweltering, overcast day in August, the smell of excrement is overpowering. After seeing dead fish on the surface, Chen, 45, wades barefoot into his murky pond to open a pipe that adds fresh water from a nearby canal. Exporters buy his fish to sell to U.S. companies.
Yang Shuiquan, chairman of a government-sponsored tilapia aquaculture association in Lianjiang, 200 kilometers from Yangjiang, says he discourages using feces as food because it contaminates water and makes fish more susceptible to diseases. He says a growing number of Guangdong farmers adopt that practice anyway because of fierce competition.