Radio 1 DJ Scott Mills’ show is being investigated after “derogatory” jokes were made on air about Essex girls.
Broadcasting watchdog Ofcom received two complaints about the jokes aired during a 24-hour show for Comic Relief.
They were made by guest Bobby Norris, from reality TV show The Only Way Is Essex (Towie), on the show last month.
A spokeswoman for Radio 1 said: “No offence was intended by the jokes that were broadcast during Radio 1’s 24-hour Lolathon.”
An Ofcom spokesman said it was investigating whether the programme “breached our rules on generally accepted standards”.
Mr Mills, who co-hosted the marathon show with fellow presenter Chris Stark, introduced listeners to his guest, telling them he was there to do a “couple of sets of Essex girl jokes”.
“I’d like to point out, before anyone complains, this is a person from Essex, living in Essex on a show [Towie] about Essex,” he added.
However, two people did complain, Ofcom confirmed.
A spokesman said: “Several ‘Essex girl’ jokes were broadcast which listeners felt were sexist and derogatory.”
Some of the lines broadcast during the 15 March show which sparked the complaints included, “what’s the first thing an Essex girl does in the morning? Goes home.”.
The term “Essex girl”, which first came into use in the early 1990s, is included in the Oxford English Dictionary, which defines it as “derogatory” and “a contemptuous term applied to a type of young woman, supposedly to be found in and around Essex, and variously characterised as unintelligent, promiscuous and materialistic”.
A campaign aimed to remove the term from the dictionary.