The FDA issued an alert of a voluntary recall for certain medicines that contain the active ingredient valsartan, used in treating high blood pressure and heart failure, over concerns of an impurity found in the recalled products.

The impurity stems from N-nitrosodimethlyamine, whose presence in the products was thought to be related to manufacturing process changes. The chemical is listed as a probable human carcinogen.

Last week, the same impurity triggered an EMA review of medicines containing valsartan supplied by Chinese company Zhejiang Huahai Pharmaceuticals.