N-nitrosodimethylamine (NDMA), a probable human carcinogen, was discovered in the valsartan medication that is manufactured by Chinese company Zhejiang Tianju, according to the EMA press release.
NDMA is an organic chemical that can be used to make liquid rocket fuel and can be unintentionally introduced into other substances through certain chemical reactions, according to the US Environmental Protection Agency. It is also a byproduct of the manufacturing of some pesticides and of fish processing.
The impurity probably dates back to changes in the manufacturing process made by the company in 2012, Channel News Asia noted.
"EMA is working closely with international partners to review the impact of the NDMA detected in valsartan from Zhejiang Tianyu and will communicate as soon as additional information becomes available," the press release noted.
Friday's recall follows recalls of the drug last month made by a different manufacturer, Zhejiang Huahai, and accompanies a new set of recalls by the US Food and Drug Administration of valsartan drugs made by that same manufacturer.
"The NDMA levels detected in batches of valsartan from Zhejiang Tianyu are much lower than levels seen in the active substance from Zhejiang Huahai, which triggered a recall of several valsartan medicines in July 2018," the EMA noted.
CNN noted July 6 that 22 countries had already recalled the drug when the FDA made its first recall.
"We published our recall notice at midday on July 13 in China and overseas, and published the US market recall notice on July 14 Beijing time," Zhejiang Huahai said in a statement to the Shanghai stock exchange last month. "All the drug materials for the Chinese market were recalled by July 23."
The danger posed by the drug is not serious. "There is no immediate risk to patients," the EMA noted. "Patients should not stop taking any valsartan medicines without consulting their doctor or pharmacist."
The FDA estimated that if 8,000 people took the highest dose of valsartan (320 mg) from the recalled batches every day for four years, there may be one additional case of cancer.
