A handful of ground cinnamon brands may contain unsafe levels of lead, the U.S. Food and Drug Administration said Tuesday.

In a third public health alert about the spice this year, the agency identified nine additional brands sold at retailers in seven states.

The agency first began issuing alerts on ground cinnamon products in March, when product tests revealed some brands contained elevated levels of lead and could be unsafe following prolonged exposure. The initial announcement involved six brands sold in six states, most of them available at discount and ethnic markets including Save-A-Lot, Dollar Tree, Family Dollar and Patel Brothers.

It issued a second public health alert for additional ground cinnamon products last week.

On Tuesday, the FDA advised consumers to stop using and throw away ground cinnamon products from even more brands, including SWAD (sold at Patel Brothers), Supreme Tradition (sold at Dollar Tree) and ALB Flavor (sold at Eurogrocery).

Three of the nine companies in Tuesday’s public health alert have already recalled the products because of possible health risk. The FDA is encouraging all of the companies to voluntarily recall the affected products.

The agency said it is analyzing cinnamon samples it receives from state partners who continuously sample cinnamons sold at retail for elevated lead levels.

Because cinnamon has a long shelf life, the FDA said consumers should check their homes for the affected products and refrain from eating, selling or serving foods that used them and instead throw them away.

It noted that most people who are exposed to lead have no immediate or obvious symptoms. Lead poisoning happens when the heavy metal builds in the body over the course of months or years, according to the Mayo Clinic. Symptoms, including abdominal pain and headaches, don’t normally appear until lead levels are substantially elevated.