Do we need background checks for house plant buyers?

The ricin poison found in a Las Vegas hotel room is so deadly that a speck the size of a pinhead could kill you.

The hotel occupant is still unconscious in a hospital, but the ricin was made from castor beans, which come from a plant that is "enduringly popular" with all sorts of suburban gardeners, says Barbara Bates, horticulture educator with the University of Illinois Extension office in St. Charles.

"Castor bean is a great way to turn your garden tropical on a budget," reads the U of I's "Tropical Punch" Web site that lists the castor bean plant as a "tropical plant to consider." Tucked into the information about the quick growth, giant leaves and dramatic colors is a small warning that "the seeds are extremely poisonous."

The Internet offers tons of castor bean plants and beans for sale. Some sites push it as a good way to kill moles and other garden pests. Many warn you to keep pets and kids away from the plants or beans. A few profess to tell you how to make ricin from castor beans.

After a murder/suicide in 2004, a discovery of castor beans in an Aurora townhouse led to a search by a hazardous materials and weapons of mass destruction team. Police found no ricin but did discover a few guns and a stash of castor beans.

Yet there is no movement to ban castor bean plants, require background checks for purchases or set limits on how many seeds a gardener can buy a month. Nor is there a National Castor Bean Association vowing not to surrender beans until we pry them from their cold, dead hands.

It's just a plant. A plant used to make laxatives, lubricants, cancer treatments and, under the wrong circumstances, super deadly poison.

Castor bean-related poisoning "does number in the hundreds of cases," says Dagny Olivares, health communication specialist at the Centers for Disease Control and Prevention. But deaths are rare, especially since eating castor beans (always a bad idea) doesn't always result in poisoning.

The CDC lists a few deaths from people injected with the castor bean extract, but Olivares notes that ricin has not been a weapon favored by killers or terrorists.

Some ricin dust showed up in envelopes in the wake of the Sept. 11, 2001, attacks when fears about anthrax or other poisons dominated the news, but no one was killed.

The most famous castor bean extract death was Georgi Markov, a Bulgarian dissident who was killed in 1978 when an assassin in London used a spring-loaded umbrella to inject him with a platinum pellet containing a fatal ricin dose.

In the United States, where our killers tend to be lazy, nonscientific, impatient types who choose easily available weapons, concocting exotic poisons from house plants "might make a better novel," Bates says.

Castor beans might be the weapon of choice if you're a spy trying to outwit Scotland Yard, but there are no cases of castor beans being used successfully among mopes trying to do in a spouse or get the upper hand in a bar fight.

If toxic plants ever do become weapons of choice, we have dozens in our arsenal -- from hemlock and wolfsbane to bleeding hearts and poinsettias.

"Just because it comes from a natural plant doesn't mean that it's safe. Some of our most toxic substances are natural," Bates says, noting the opium poppy for starters.

"Apple seeds have cyanide in them. If you ate a lot, you could get sick or kill yourself," Bates says. "But people don't eat a cup of apple seeds."

There's no need to elevate your personal Homeland Security System rating to red just because your neighbor's patio boasts a wall of castor bean plants.

"With it in the news, Americans are going to be concerned about it," Olivares says. "You should read and learn about it and put it in the proper perspective."

If all we have to fear are house plants, we will be in good shape.