A tank containing around 15,000 tons of sulphuric acid sprang a leak at Kemira, a chemical company. The accident happened early on Friday morning and a poisonous cloud formed as the acid reacted with water.
Fire inspector Ronny Möller says that Kemira has already a theory on what may have caused the accident.
“We think one of the underground pipes containing antifreeze leaked and undermined the soil under the tank that stores sulphuric acid.”
Lennart Johansson, who is the managing director of Kemira, told Sydsvenskan that this is the first time an accident of this nature has happened. The next step will be to review the security measures of the company.
Inhabitants of Helsigborg were told to not leave their homes because the cloud was moving towards the city centre.
However, some had already left for work and could not return while others were simply unaware of the emergtency.
Gabriella Sjöström and her mother Anne-Jeanette, who live in the area, woke up two hours later, with a phone call from a friend.
“We ran down to the basement and took as many towels as we could find,” Anne-Jeanette told Göteborgs-Posten.
“The radio told us to wet them and put them by the windows and doors. It was not fun. I have always been scared of an accident like this.”
Ulf Rick, a chemist at the Swedish Chemicals Inspectorate, told Sydsvenskan that a cloud of gas of this kind can be deadly and an accident like this one should not be able to happen.
“You can die from the wounds caused by the high corrosiveness,” he said.
An extensive area around the plant was closed by the police but was reduced three hours later to one kilometre in each direction from the company. Public transportation and ferry traffic were also stopped.
As well as the Accident Investigation Board, the police have also begun investigating the company and may charge it with breaking environmental laws.
According to TT, seven people were taken to the hospital with symptoms of poisoning. Six of them were experiencing breathing problems. They were kept at the hospital for observation, but are out of danger.
“Those affected by the gas will develop an early reaction, with coughing and a burning sensation in the eyes,” said Ronny Möller to DN.
After the accident, Helsingborg said to have become “a ghost town”. Streets and squares were empty since people were encouraged to stay indoors with closed windows and doors.
On Sunday afternoon local residents were allowed to leave their homes and by Monday morning, according to Göteborgs-Posten, only the accident area itself was still cordoned off.