Poinsettias: pretty plants with a bad rap

Childproofing for the holidays usually involves putting those showy, toddler-beckoning poinsettias beyond the reach of small hands. But the now ubiquitous Christmas plants have an undeserved reputation for being poisonous. A small child could actually eat up to 500 leaves with little effect -- if he could withstand the terribly bitter taste.

Whence this fear of the holiday plant, then? The source of the myth is often traced to Hawaii, 1919, when an Army officer’s son died after supposedly eating the leaves of a poinsettia.

The diagnosis was later disproved, but the fear, apparently, stuck. Poinsettia exposures are consistently among the top plant exposures people report to poison control centers -- even though scientists keep proving them safe.

Researchers in the 1970s and 1980s force-fed poinsettia leaves to rats, to little effect. Some rats had slightly enlarged thyroids a week later, but they ate far more relative to their weight than most humans -- including curious infants -- could probably eat without getting bored, or throwing up.

In the 1990s, researchers in Pittsburgh reviewed more than 22,000 cases of people who had contacted poison control centers to report possible poinsettia poisonings. More than 92% of the cases (the vast majority were children) had no symptoms.

What about the 8% who didn’t feel too good after a taste of the red leaves? Eating just about anything that tastes as bad as a poinsettia can make a person vomit or feel nauseated.

And some people, it turns out, are allergic to the holiday plant.

Earlier this year, a doctor at a hospital in Japan reported two cases of infants who went into anaphylactic shock after contact with poinsettia leaves.

On further investigation, the doctor learned that both infants were also allergic to latex. The hospital conducted a follow-up study and found that latex and poinsettia allergies often go hand in hand. Poinsettia and the Brazilian rubber tree -- the source of latex -- are in the same plant family, and the two share some allergen proteins.

The poinsettia has something else in common with the Brazilian rubber tree: It also emerged from Latin America in the 1800s to become popular around the world.

In the 1820s, former war secretary and ambassador to Mexico Joel Roberts Poinsett brought one of the spindly, winter-blooming flowers back from Mexico to his South Carolina home. Inspired by the poinsettia’s red, winter-blooming flowers, he cultivated it into a popular holiday plant.

In its native Mexico, long before Poinsett came along, the poinsettia was a symbol of new life. The Aztecs used the plants’ deeply colored leaves to make dye for cloth, and used the sap to make a medicine for fever. Apparently, they had quite a bit of faith that the plants were safe -- but one can only imagine how that medicine must have tasted.

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The history of the poinsettia: www.pauleckepoinsettias. com/html/hist_fset.html