California public health officials are warning people not to eat cactus imported from Mexico because of the presence of unapproved pesticides, ABC News reported.

As much as 5.8 parts per million of Monocrotophos, an organophosphate-based pesticide that has been banned from the United States since 1989, has been found in the imported cactus during a recent routine testing by the state's Department of Pesticide Regulation, ABC News reported.

Monocrotophos is "extremely toxic to birds and is used as a bird poison. [The pesticide] is also very poisonous to mammals," according to Cornell University.

In a prepared statement, California's Department of Public Health said the cactus was sold at five specific retail and wholesale locations in California, including   La Superior Supermercado in Pittsburg, Mercado del Valle in Concord, La Sucursal Produce, Fresh American Produce, and J&L Produce located in Los Angeles.

The product was reportedly sold to retail stores in bulk bins without any specific labeling or branding. Whole cases of the cactus purchased from the wholesale produce companies were likely labeled with a supplier sticker that stated "Comercializadora De Chiles, Selectos Nieto S. De R.L. De C.V."

No illnesses have been reported to date, but symptoms of acute poisoning may include sweating, headache, weakness, nausea, vomiting, hypersalivation, abdominal cramps, and diarrhea.

Consumption of Monocrotophos can lead to neurotoxicity and permanent nerve damage.

"Washing or peeling the cactus prior to preparation as well as some cooking methods (boiling) can remove some of the pesticide, however, since consumers are unable to measure the effectiveness of these procedures, it is not recommended that consumers try to salvage any of this contaminated product," California public health officials said in a statement.

If consumers have any of the affected products remaining in their possession, they should return it to the place of purchase or dispose of it in the garbage.