Advertising: Radio watchdog on guard as Evans talks up his sponsors

Chris Evans' style of broadcasting allows him to take in everything around him and use it as humour. But Paul McCann, Media Correspondent, warns that the DJ is in danger of overstepping the mark.

The radio industry's watchdog is investigating the Virgin Radio breakfast show after complaints by listeners about the way he talks about the programme's sponsors during his show.

The Radio Authority, which regulates commercial radio stations, has requested a tape of one of Chris Evans' shows and has already had discussions with the station about so-called "product placement" - where a broadcaster's mentions of a sponsor's products during a show cross the line between editorial and advertisement.

According to rule six of the authority's sponsorship code DJs are not permitted to endorse a sponsor's product or service within the editorial of a show. Instead sponsor's credits are usually at the beginning and end of shows or before traffic round-ups and weather reports. However there is a grey area where DJs can mention commercial products, including the sponsor of the show, as long as it is not seen as an explicit endorsement.

The listeners who have complained feel that Evans' use of a sponsor's name as part of an extended humorous "rap" with his team in the studio may be breaking the RA's code. For instance, on Thursday morning Evans even declared on air that his sponsors got good value from him.

Earlier this week the company owned by Chris Evans which owns Virgin Radio, Ginger Media Group, signed a pounds 3m sponsorship and programme development deal with the satellite broadcaster BSkyB. Following this deal the DJ has started comparing BSkyB programmes with BBC ones. While the humorous implication of Evans' skits is that the BBC's programmes are dull compared to those of BSkyB, he has been careful not to explicitly recommend that listeners watch BSkyB. Instead he ends the skit by saying that listeners can decide for themselves what to watch. Virgin is known to believe that this protects the DJ from accusations of endorsement.

In addition to the sponsorship deal the DJ is known to have become good friends with Elisabeth Murdoch, the daughter of Rupert Murdoch, owner of BSkyB and programming director of the satellite channel. The two have been seen and photographed out on the town together, including at a reception at Downing Street. The other main sponsor of the show is the Czech beer Pilsner Urquell. Again, the breakfast show "zoo" - Evans' on-air radio team - hooted when one of them said she had never drunk the beer and Evans said she had been told off for her lack of support.

"This is a matter that has been discussed and we will monitor the station," says David Lloyd, the Radio Authority's head of programming and advertising. "The dangerous thing is if mentions of a product become endorsement by being gratuitous rather than of editorial merit."

The authority has already rejected one complaint from a listener and is investigating another. Mr Lloyd believes the concern with Chris Evans is that his style of broadcasting takes in everything happening to him and all that surrounds him: "Chris Evans is known for testing the boundaries. Given his track record we contacted Virgin to show them the rules".

John Pearson, Virgin Radio managing director, said: "It is our intention to stay within the guidelines. However, it is also our intention to be innovative in the way we use sponsorship and make it interactive with the programme."