According to France’s Le Parisien newspaper, 22 people were intoxicated by a bad mix of bleach and sulfuric acid which was made in the hotel pool tank. The outlet reports that around 12:30 p.m. on Friday, the tank unleashed a toxic smell while people were swimming. The Local reports the incorrect mix emitted a chlorine gas that caused guests nausea and breathing issues.
When liquid chlorine is released, it turns into a gas that stays close to the ground and spreads rapidly, according to the CDC. Chlorine gas can affect people through skin contact, eye irritation or inhalation. If inhaled, the toxic chemical gas can cause difficulty breathing, nausea, blurred vision, skin blisters and coughing.
Disneyland Paris staff evacuated the pool and rooms on the hotel’s upper floors which were located near the pool, and firefighters and an emergency response team arrived.
WATCH THIS: Woman Unexpectedly Gives Birth After Mistaking Pregnancy for Food Poisoning
Le Parisien reports that three employees and one hotel guest were transported to the hospital for non life-threatening injuries. While the pool was closed for the rest of the day Friday through Saturday morning, around 5:30 p.m. on Friday, after firefighters pumped the toxic substance from the tank, police began allowing customers to return to their rooms. However, according to the outlet, the staff offered the affected guests relocation to a different hotel wing.
Disney did not immediately return PEOPLE’s request for comment.