The move follows a report in a foreign newspaper that said macromolecule plastic and some other toxic chemical substances were being used to increase the toughness of tapioca balls, the key ingredient in bubble tea, Cuong said.

The department had conducted a quality inspection of the bubble tea early this year, Cuong said, adding the results showed food coloring and sweeteners used at allowed levels.

In the upcoming inspection, the group will take samples of bubble tea to test whether or not it contains substances harmful for users’ health, Cuong said.

Cuong added the group will take samples of bubble tea at markets as well as shops serving the tea, as was done previously.