Residents of an apartment complex in Dinh Cong Ward, Hanoi, say they have been unable to open their windows or balconies for three days as milk flower trees around the grounds have come into full bloom.
The strong scent has caused headaches and discomfort, they said.
Security staff spray water on the milk flower trees on the evening of October 13 to reduce the scent's impact on residents' lives (Photo: Nguyen Ngoan).
Huy, 37, lives on the fourth floor, level with the tree canopies. Four milk flower trees stand beside his bedroom window, while another six grow in front of his balcony.
Surrounded by the trees, his family has had to keep their windows and doors shut and run an air purifier to keep the smell out.
Huy said he normally opened the windows to let fresh air into the apartment but avoided doing so during the flowering season.
“As soon as we open them, the smell rushes in. It is not a faint fragrance but an overpowering odour that we cannot tolerate,” he said.
Residents on higher floors have also been affected.
Lien, who lives on the 10th floor, said about 12 milk flower trees around the complex had bloomed at the same time, leaving her with headaches for several days.
Sensitive to strong smells, she has barely opened her windows or balcony doors since the flowers began blooming. After work, she now heads straight to the underground car park and takes the lift directly to her apartment to minimise the time she spends outside.
“I used to sit in the lobby and chat with other women in the building, but for the past few days I have stayed indoors with the doors closed because I cannot stand the smell,” she said.
Looking at the dense clusters of flowers on the branches, Lien said she could only hope for heavy rain to knock some of them down.
A high-pressure hose was used to spray the tree canopies (Photo: Nguyen Ngoan).
Security guards at the complex have also noticed the unusually strong scent.
One guard said it became more intense in the evening and at night. He now wears an additional face mask when patrolling the front and rear entrances during his shifts.
“One or two trees with a faint scent would not be a problem, but when so many bloom at once, the smell becomes overwhelming. It can make breathing uncomfortable and block the nose, and prolonged exposure causes headaches,” he said.
In response to complaints from residents and security staff, the apartment management instructed guards on the evening of October 13 to connect a fire hose to the complex’s water tank and spray the row of milk flower trees in front of the main entrance.
A management representative said the spraying lasted about 10 minutes. Water was directed at the flower clusters to knock some of them off and reduce the scent spreading through the residential area.
“We sprayed the trees after receiving numerous complaints that the smell was disrupting daily life, particularly in the evening and late at night,” the representative said.
Security staff collected the fallen flowers that evening to keep the grounds clean. Management will continue monitoring the situation and may spray the trees again if the smell remains strong enough to disturb residents, the representative added.
After the blossoms fell, security staff cleared them away the same evening to maintain hygiene standards (Photo: Nguyen Ngoan).
Dr Bui Van Khanh of the Clinical Allergy and Immunology Centre at Bach Mai Hospital said milk flowers were a familiar feature of autumn in Hanoi but could also trigger allergic reactions and irritate the airways in sensitive people.
People prone to allergies should limit outdoor activities when pollen levels are high, keep windows closed, use air purifiers and wear sunglasses outdoors, he advised. After returning home, they should shower and change and wash their clothes to remove pollen and reduce the risk of exposure.