The European Medicines Agency estimates there could be one extra case of cancer for every 5,000 patients taking a common blood pressure and heart drug manufactured in bulk by a Chinese company that has been found to contain an impurity.
The alarm over valsartan was first raised in July, prompting a global recall of affected pills. The EMA believes the problem likely dates back to changes in manufacturing processes at Zhejiang Huahai Pharmaceutical in 2012.