We've heard of rats in kitchens of city restaurants - but of plane galleys? Not so common.
Rat droppings 'too numerous to count' and urine were found on a Delta airlines plane in the area where food and drink is stored.
The large amount of faeces was found during a routine check by US health inspectors at the end of January.
The FDA sent chief executive Richard Anderson a letter detailing the violations found at Delta's hangar in Atlanta International Airport, and they responded that it had 'been cleaned up and returned to service within days'.
According to the Daily Mail, spokeswoman Ashley Black told Bloomberg News that they were taking the issue very seriously and that the carrier had humanely caught the animal.
She said: 'We believe this was an isolated incident and we cooperated with the FDA immediately to resolve it earlier this year. The health and safety of Delta's customers and employees are Delta's top priority.'
She declined to specify the type of plane involved, other than that it was used on international flights.
Lab results confirmed the presence of rat excrement and rodent urine stains in the aircraft, the FDA said in its letter.
Federal regulations for transportation companies require that 'all places where food is prepared, served, or stored shall be constructed and maintained as to be clean and free from flies, rodents and other vermin'.
Chad Artimovich, president of Atlanta Wildlife Solutions LLC, a pest-control company, told Bloomberg News that a roof rat is the most likely animal to infest an airplane.
He said these rodents leave as many as 50 droppings a day and a jetliner provides 'everything a rat needs' with spilled nuts and pretzel crumbs and sources of water.
He said: 'Once it gets in there and gets established, there's no reason to leave. The real concern is if a rat started chewing on wires.
'Almost every house I go into where there are rats, they've chewed on wood and wiring and ornaments. Their teeth are harder than iron and they have to keep them gnawed down.'
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