Chlorine gas poisoning symptoms, illness, and treatment after Olympic Park leak

29 people were taken to hospital today following a chlorine gas leak at the Queen Elizabeth Olympic Park in Stratford East London. The source of the leak was later discovered to be a chemical reaction during the delivery of new chemicals to the Aquatics Centre, where 200 people were swimming at the time.

When the leak was discovered these swimmers were forced to quickly evacuate the building with witnesses describing the scene as alarms rang out and people ran “coughing and covering their faces”, a strong smell of chlorine filling the air. In total 77 of these people were then treated for injuries relating to chlorine exposure, London Ambulance Service noting that most of these were individuals experiencing “minor breathing difficulties”.

Later when London Fire Brigade were ventilating the Aquatics Centre, flushing the remaining chlorine out of its airways, they advised residents in any neighbouring residential buildings to “stay indoors during this time and keep all windows and doors closed.”

READ MORE: East London residents complain of waking up to mystery stench that smelt so bad they were ‘afraid to breathe’

What is chlorine, and what happens when you’re exposed to it?

Chlorine solution is normally used for cleaning swimming pools in a low quantity. But, the London Fire Brigade reported “a high quantity of chlorine gas was released” after a chemical reaction at the swimming centre this morning. Witnesses have also described smelling the chemical as they fled in their swimwear.

The gas can be deadly in high quantities and was notoriously used during World War One, before the Geneva Convention banned chemical weapons, where the gas killed more than 2,000 unprotected British soldiers – injuring approximately another 165,000 in the process.

The UK Health Protection Agency says that because chlorine is a gas in its natural state, the most likely way you’ll be affected is in your eyes and lungs through inhalation.

In these circumstances low quantities can cause “lung and eye irritation”, while high amounts can lead to “coughing and breathing difficulties” as fluid builds up in the lungs. These are all symptoms that have been reported by emergency services treating casualties at the Olympic Park today.

The HPA also warns “a number of accidental domestic exposures to chlorine arise each year through the inappropriate mixing of domestic cleaning products or incorrect use of swimming pool disinfectants.”

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