The 16- and 14-year-olds, who can’t be named for legal reasons, were charged with possession of a corrosive substance in a public place.
Officers from British Transport Police were patrolling the station on Friday afternoon when they spotted two people acting suspiciously.
As officers engaged with the people, they were exposed to a substance believed to be alkaline.
Two officers were taken to hospital and have since been discharged and seven others were checked at the scene by paramedics.
