A voluntary recall for blood pressure medication that may contain a potentially cancer-causing impurity in humans has been expanded. It's the latest in dozens of recalls for blood pressure medication since last July.

Teva Pharmaceuticals USA is expanding its April 25 recall for losartan potassium tablets because they may contain N-Nitroso-N-methyl-4-aminobutyric acid (NMBA) at levels higher than the FDA's acceptable exposure limit.

The expanded recall involves six lots of bulk losartan potassium USP Tablets. Two lots are of 50 mg strength and four lots are of 100 mg strength. 

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The bulk lots were sold to Golden State Medical Supply, Inc., packaged under GSMS's own label and distributed in retail bottles of 30, 90 and 1000 tablets, according to the company. A full list of these is available at this link.

The FDA has stated throughout these recalls that the risk of developing cancer by taking these recalled medications over a long period of time is extremely low, but the risk is still there. 

"The FDA calculated that if you took the very highest dose of one of the affected medicines over four years, and you took the medicine that was the most contaminated, the risk is an additional one case in 8,000 people," said Janet Woodcock, director of the FDA's Center for Drug Evaluation and Research, in a video statement earlier this year.

Patients have been consistently advised to not quit their blood pressure medication until they talk to a doctor about alternatives.

People wishing to return their medications are advised to contact Teva’s product recall processor. Contact Inmar at 877-789-2065 between 9 a.m. and 5 p.m. Eastern Time, Monday – Friday or email Inmar at tevarecalls@inmar.com. Teva says Inmar will provide the materials needed to return the medication and get instructions for reimbursement.