A white metal cylinder containing 100 pounds of lethal sulfuryl fluoride was stolen this weekend from a Hillsborough exterminator's truck.
The chemical, under the trade name Vikane, is used to fumigate tented homes for wood termites. It is deadly when inhaled.
"We're concerned about this cylinder being stolen. If it does show up, we don't want anyone to get hurt," said Steve Day, manager of the Tampa branch of Clearwater-based Ace Professional Pest Control Inc.
The cylinder is 4 feet long with Vikane printed in blue letters. Also on the tank are green warning and danger labels, and a skull and crossbones.
Vikane, which can be released through a valve that easily opens with a wrench, is a liquid that turns into an odorless, colorless gas when exposed to air. The gas affects the central nervous system.
The missing tank contained enough liquid gas to chemically treat a large building, Day said.
According to Day and Hillsborough sheriff's reports, someone broke the gate at the pest control company at 8808 Venture Cove late Friday or early Saturday and broke into a locked truck where the tank was stored. Day said employees discovered the theft Saturday.
They suspect someone may have taken the tank intending to treat a termite-infested building. Officials said they fear someone could be killed if the valve is opened incorrectly.
Exterminators are certified through the state Department of Agriculture and must take annual tests. Vikane, when used properly, is dispensed through a hose into a sealed building. It dissipates quickly when exposed to fresh air but can kill in confined spaces.
Officials warned against touching the tank and asked anyone who sees it to call the Sheriff's Office at 247-8200.
_ Times researcher Beverly Bell contributed to this report