The story on National Tropical Botanical Garden said that people should not come close or touch the leaves, seeds or bark of van tue tree (Cycas revoluta).

Scientists have found out that the alkaloids compound in the tree trunk can cause cancer, while amino acid is the factor that causes chronic mental disorder, and cycasin in the seeds also contains high toxicity.

Therefore, people have been advised to reduce contact with van tue trees or put the trees in closed rooms, because the trees would bring diseases or even cause death to people. The trees should be put out of the reach of children, because they may be hurt if they accidentally touch the trees.

Van tue trees have been grown everywhere in Vietnam. Especially, they have been favored by families, because “van tue” in Vietnamese means “long life.” Some people grow van tue in the gardens in front of their houses, but many others like putting them inside the rooms as ornamental trees.

Dr. of Biology, Bui Van Le from the HCM City University of Natural Sciences, has provided a list of 22 toxic ornamental trees which have been very popular in Vietnam.

Truc dao, or Nerium oleander is one of them. Le said toxicity - Oleandrin, Neriin - can be found everywhere on the trees. People would get poisoned if they just touch the trees or swallow parts of the trees. If so, they would suffer cause nausea, vomiting, diarrhea, cardiac arrhythmias, or fall into coma. In serious cases, the poisoning would lead to death.

The toxicity would still exist even if the trees are dried or boiled. Therefore, people have been advised not to grow truc dao near the water resources (water tanks, water wells). The falling leaves and flowers of truc dao can poison the water.

Truc dao have been grown on many streets, in parks as ornamental trees, while no one has been informed about the high risks of the trees.

Le also believes that Do quyen, or Rhododendron simsii Planch, also has high toxicity, Andromedotoxin and Arbutin glucoside. A small amount of 100-250 gr of do quyen would be enough to cause serious poison to a 25-kilo child. The latex of cactaceae is believed to make someone blind.

All kinds of the trees have still been grown in a large scale in Vietnam, simply because people lack information about the trees.

In fact, Vietnamese decide to grow or not grow these or that kinds of tree just because they believe the trees would bring luck and prosperity, while they do not care about if they are toxic or if they can help treat diseases.

Landlords only consider the size of trees, the color and the style and consult with experts about if the trees would suit the family members.

A lot of people like leaving fresh flowers in their bedrooms, while many of them died because the flowers took all the oxygen and generated fragrance. In HCM City, some children reportedly died after eating ma tien fruits (Strychnos nux-vomica

(Lao Dong)