The Food and Drug Administration announced Friday that low levels of a cancer-bound chemical have been found in Zantac heartburn medicine.
The chemical is an impurity called NDMA, which has been linked to an increased risk of colon cancer and uterine cancer.
The FDA stated that low levels of NDMA were found in samples of ranitidine, a substance used to treat and prevent heartburn by reducing gastric acid. It is sold under the brand name Zantac.
It is unclear where the pollution originated. NDMA is the same chemical that has led to several recalls of blood pressure medication over the past year.
So far, there is no recall of Zantac or medicines containing ranitidine.
The FDA said it is still considering whether the levels found in antacids would pose a health risk to millions of people taking them, and has said that people should not stop taking heartburn medicine until more is known.
Health officials in Europe announced Friday that they are also investigating NDMA contamination in ranitidine.
Other heartburn medicines on the market, such as Prevacid, Nexium and Prilosec, have different ingredients and are not included in this notice.
"Patients should be able to trust that their medications are as safe as they can be and that the benefits of taking them outweigh any risks to their health," said Dr. Janet Woodcock, director of the FDA's Center for Drug Evaluation and Research, in a statement.
"Although NDMA can cause large amounts of damage, the levels the FDA finds in ranitidine from preliminary tests barely exceed the amounts you might expect to find in regular foods," the statement continued.
According to the Centers for Disease Control and Prevention, NDMA has been detected in tobacco smoke, chewing tobacco and cured meats such as bacon.
Ranitidine is sold over the counter as a heartburn medicine, but is also used as a prescription for the treatment of gastric ulcer and gastroesophageal reflux disease.
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