Houseplants can cause allergic reactions

When people come down with a runny nose and itchy eyes in their homes, they often think the cause is an allergy. The usual suspects are dust mites and pets. They should, however, also consider their houseplants.

"Basically, any houseplant can set off an allergy," said Stefan Gentzen, director of the German garden retailers' association in Berlin. "At the time of the sale customers generally don't know that they will have an allergic reaction to the plant."

There are, however, plants that are known to cause allergic reactions. The best-known example is the ficus, (Ficus benjamina), also known as the weeping fig or Benjamin's fig.

"The ficus is found in almost every office building and in many private homes. That's why it is known for touching off allergies," Gentzen said.

The plant's allergens come from the milky sap on the surface of the leaves.

"The types of immediate reactions are running nose, itchy eyes and respiratory problems similar to asthma. Hours later eczema could develop," Anja Schwalfenberg, patient adviser at the German allergy and asthma association in Moenchengladbach said.

Less well known is the allergic potential of plants in the Asteraceae family such as chrysanthemums and daisies.

"Their allergens are dispersed in an area through pollen and can cause sniffles or asthmas," said Thomas Fuchs, president of the professional association for Germany allergists.

People who know that they are allergic to a specific plant should keep away from that plant, Fuchs advised.

allergic  (adj.)   过敏的；引起过敏反应的

to come down with   病倒；染上

dust mite   尘蹒

to set off   引起；引发

best-known   最着名的；最（为人熟知的）

to touch off   促成；引发

milky  (adj.)   乳状的；乳白色的 

asthma  (n.)   气喘；哮喘

to disperse  (v.)   散开；分散

pollen  (n.)   花粉