WAILUKU, Maui — State laboratory tests on cans of Cattle Drive chili suspected of sickening two Maui men came up negative for botulism, according to a Health Department official.

The department is still awaiting the results of testing of blood and stool samples collected from one of the men, Jon Stockton, 33, of Hana, said spokeswoman Janice Okubo. The samples were sent to the U.S. Centers for Disease Control and Prevention.

Stockton went to the Maui Memorial Medical Center emergency room July 26 after suffering symptoms that included numbness in his face. He said he had eaten the chili July 23, put an open can in the refrigerator overnight and ate it again the next day. He became ill with stomach problems and achiness, with the symptoms worsening as the week progressed.

Stockton was hospitalized for two days.

Wailuku attorney Keith Regan, 35, reported that he became sick after eating Cattle Drive chili July 20, suffering from severe stomach distress, tiredness and blurred vision over the course of the next week.

Okubo said that Regan's symptoms did not meet the criteria for botulism, so blood and stool samples were not collected for testing.

"The Stockton case meets some, but not all the criteria for botulism," Okubo said. "There are other possible causes to his illness that have not been ruled out. Physicians make diagnoses on the best available evidence at the time."

The Health Department's laboratory examined an unopened can from Stockton's house, she said. The can he had actually eaten from had been discarded.

One opened and consumed can from Regan's home also was tested. Both cans showed no signs of botulism contamination, Okubo said.

Both Stockton and Regan said they purchased the chili at Costco in Kahului before a series of product recalls were announced by manufacturer Castleberry's Food Co. of Augusta, Ga., starting July 18. An investigation traced the source of botulism to a set of commercial-scale pressure cookers at a canning facility in Georgia.

Costco officials said the products were immediately pulled from shelves when an expanded recall was announced July 21, and that customers who purchased the recalled items are being notified.

There have been at least four confirmed cases of botulism related to Castleberry's products, two each in Texas and Indiana.

Botulism is a rare but serious illness caused by consuming foods tainted by botulinum toxin. The toxin, produced by the bacterium Clostridium botulinum, affects the nervous system and can cause paralysis and death.

Symptoms of botulism include double or blurred vision, drooping eyelids, slurred speech, difficulty swallowing and/or muscle weakness. If untreated, the illness may progress from head to toe, with paralysis of the face, arms, breathing muscles, torso and legs.

Reach Christie Wilson at cwilson@honoluluadvertiser.com.