Laboratory tests confirmed that 2-year-old Alexei Wiltsey and his 3-year-old brother Peter died of oleander toxicity, coroner's office spokesman Scott Carrier said. The two were found dead in their cribs at their El Segundo home on May 4. The chemical oleandrian in the popular garden plant causes the heart to stop beating, according to the coroner.
That the boys died from eating the plant was no surprise to Scott Appell, director of education at the Horticultural Society of New York, who joined CBS News' Early Show Thursday.
"Oleander is lethal. And one leaf alone is enough to kill an adult," Appell said.
Oleander is among several common household and garden plants that can kill, Appell said.
"I have read reports where families had unintentionally poisoned themselves because they used the branches as shish-kabob skewers," he added.
The boys' mother, Shirley Wiltsey, said she found the boys chewing oleander leaves a few days before they died and noticed they had picked some again the night of their deaths.
Shirley and her husband Tom Wiltsey adopted the boys in August from an orphanage in Siberia. Authorities had speculated that the deaths were related to an rare mental disorder caused by the boys' having been born in hunger and poverty.
Although the plant is fatal for adults and kids, children's small size can made them more susceptible to the poison, Appell said. Pets can also be poisoned.
Ingestion of the plants causes the danger, and care should be taken to avoid inadvertent poisoning, Appell said.
"If I was out in the garden pruning them, if I lived in Florida...or California, I'd wash my hands (afterward) by all means," he said.
Like azaleas, English ivy, foxglove, lily of the valley, mistletoe, and other types of fatal plants, oleander developed a killing chemical constituency to help it survive.
"If you're poisonous, and you're a plant, it's a survival tactic," he said. "It helps (plants) survive."
The best way to guard against poisonous plants is to know what's poisonous and what isn't, he said.
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