"She then walked off leaving them at the screening point. The contents included prohibited pepper spray."
An official had picked the item up to test it and accidentally sprayed it.
"While senior managers were reviewing security video footage as they tried to identify the passenger, one of the officers at the screening point checked the canister.
"In doing this It released a small discharge which was noticed by some passengers and caused some people to cough."
Aviation security closed two screening lanes and deployed fans to disperse the spray.
No one needed medical treatment following the incident.
"It's important for passengers to remember that items that may be in everyday use have the potential to cause harm or injury in the confines of an aircraft cabin," Richards said.