Tourists have been warned to not buy these balloons as the colourless and non-inflammable nitrous-oxide gas can cause severe symptoms for inhalers and some might even become unconscious if there is an overdose. Nitrous oxide is used in surgery and dentistry for its anaesthetic and analgesic effects.
Police Lt-Colonel Nathakon Kumsap, a deputy commander of Chanasongkram Police Station, said he would ask the Food and Drug Administration to give more details about the legal procedures against the wrongdoers as nitrous oxide is recognised as a forbidden substance, not a drug.