Cleaners are being pressured to clean pigeon muck at various stations. Any significant amount needs to be dealt with by specialists. If you are asked to do this: refuse! Do not compromise your health and safety.
Pigeon and other bird guano can contain serious amounts of harmful bacteria, as this page on the Health and Safety Executive website makes clear.
Station supervisors should not ask regular cleaners to deal with these problems; raise a job and have it dealt with by specialists, who will have respiratory equipment.