Identifying source of deadly E. coli remains a challenge

Frustration is building in Europe as the source of Germany's E. coli outbreak remains unsolved. It may even be plowed under," says Ben Chapman, a food safety expert at North Carolina State University. "It's pretty unlikely that you have a cucumber or a tomato or lettuce sticking around in your fridge six or seven weeks after being exposed," says Chapman. Related stories: Focus shifts to vegetable sprouts in E.coli outbreak 手机携带细菌量超马桶手柄！ Trying to improve food safety with a camera Death an option for some unfit food producers （来源：VOA 编辑：崔旭燕）