LIKE Earl Grey or English Breakfast, whether the radio host Don Imus is your cup of tea may simply be a matter of taste. He is brash, he is outspoken, he often says things that many people find utterly inappropriate.

And yet he has been there forever. For 30 years or more Imus has entertained and shocked listeners to his morning radio-show broadcast from New York with his own particular mix of political interviews, barbed commentary and fundraising for wholesome causes such as children with cancer. His chief goal, he once claimed, was to "goad people into saying something that ruins their life".

But not for any longer. Imus has opened his mouth a little too widely and said something that has, if not exactly ruined his life, at least brought his career to a shuddering halt.

The shock jock has been jolted into silence. The final blow came when the broadcast giant CBS announced on Thursday that it was cancelling his Imus in the Morning show. The decision - following an announcement by the television channel MSNBC that it was pulling its simulcast of the show - meant that Imus (66) no longer had a home on television or radio.

The decision to axe the shock jock had long been anticipated and it was perhaps only Imus himself who did not really believe it was coming. In the end, CBS claimed it had no real alternative but to can one of the best-known voices in US radio.

At the centre of the controversy were comments that Imus made on 4 April during a National Collegiate Athletic Association (NCAA) women's basketball match between teams from Rutgers University in New Jersey and a team from the University of Tennessee. Discussing the match with one of his radio show's contributors, Imus described the mainly black athletes on the Rutgers team as "nappyheaded hos" - 'nappy' being a derogatory reference to the hair of some black people while 'ho' is well-known slang for whore.

It provoked immediate outrage. Campaigners such as the Reverend Jesse Jackson and the Reverend Al Sharpton demanded that Imus should be fired while many of Imus's regular guests rapidly distanced themselves from him and vowed they would never appear again on his show. CBS said it would suspend Imus for two weeks without pay while it considered the matter.

In a different time and a different setting, the matter may have gone no further. Indeed, Imus had previously made plenty of inappropriate and bigoted comments on his radio show that stirred controversy but little more. But in this instance Imus picked on two hot-button topics that fuel passionate debate.

First and foremost, the topic of race and racism in the US is never far from the centre of controversy. Secondly, college athletics in the US holds an elevated and idealised position in the public imagination that is difficult for foreigners to appreciate. In making comments that were both racist and derogatory towards student athletes - and especially so in a digital age when people could download a podcast of his comments - Imus had signed his own death warrant.

Announcing the decision to cancel the show, Leslie Moonves, the president of CBS, said that in recent days senior officials had been consulting with a range of opinion formers and groups. He said:

"In our recent meetings with concerned groups, there has been discussion of the effect language like this has on our young people, particularly young women of colour trying to make their way in this society. That consideration has weighed heavily as we made our decision." In a note to CBS staff, he added: "He has flourished in a culture that permits a certain level of objectionable expression that hurts and demeans a wide range of people."

When the controversy first erupted, Imus - grey-haired and craggy-faced - made a less-than-impressive apology.

He said that his comments were an "idiotic, stupid" thing to say. The man who had earned an annual salary of about Euro7.4m said he had said a bad thing but that he was not a bad person.

In the hyperventilating, circus-like atmosphere that quickly surrounded the event, Imus found he was not the only person in the spotlight. The players of the Rutgers team agreed to meet Imus to hear his personal apology and appeared for the television cameras wearing their matching team workout clothes.

He and his wife apparently spoke with the players for three hours at a private meeting in the official mansion of the governor of New Jersey last Thursday. Standing on the steps of the mansion after the meeting, Vivian Stringer, the team's coach, told reporters:

"We had a very productive meeting.

"We were able to really dialogue. . . Hopefully, we can put all of this behind us."

But by then it was all getting a little late in the day. Imus had not helped himself with his initial apology and by his decision to appear on Al Sharpton's radio show in which he made more trouble for himself by losing his temper and referring to Sharpton's black guests that were questioning him as "you people".

By this point many of his advertisers, including American Express and General Motors, had dropped their sponsorship of his show in disgust. While the show brings in about $15m for CBS, it was clear that this was a situation that would not be allowed to continue to fester.

As the controversy continued and as the debate about race and ownership of language soared, Imus may have finally sensed the end was up.

In a tragi-comic finale, Imus's final broadcast for CBS took place last week during which for four-and-a-half hours he held a 'radiothon' to raise money for three different charities he supports - two that help children with cancer and another that campaigns on infant death syndrome.

His wife, Deirdre, who has promoted her environmental books on the show and who Imus has previously called the "Green Ho", spoke of their meeting with the Rutgers players. "They gave us the opportunity to listen to what they had to say and why they're hurting and how awful this is. And I have to say that these women are unbelievably courageous and beautiful women, " she said.

Meanwhile, Imus also railed at the decision to pull the plug on his show and accused the media of hypocrisy. "This may or may not be our final radiothon, " he told listeners. "But let's for the sake of safety say it is." Ironically, the radiothon raised more money than in previous years, proving that the clich� about all publicity having value may still be true.

The decision by CBS was welcomed by those who called for him to be fired. Sharpton said: "He says he wants to be forgiven. I hope he continues in that process. But we cannot afford a precedent established that the airways can commercialise and mainstream sexism and racism."

Jesse Jackson, meanwhile, described the firing as a "victory for public decency". He added: "No one should use the public airwaves to transmit racial or sexual degradation."

The future for Imus, once voted one of the 25 Most Influential People in America by Timemagazine, is at this point unclear. What is certain, however, is that the market for shock jocks, those people whose very purpose appears to be to push at the boundaries of taste and decency, remains as strong as ever.

Howard Stern, another notorious shock jock, left terrestrial radio for a satellite channel claiming that his often derogatory comments were being censored too often by the parent company. While his salary has never been made public, when he made the move, Sirius Radio provided a budget of $500m to pay Stern and his team's production costs. While it may get you fired, bigotry can still pay big.

RADIO'S MOST CONTROVERSIAL STARS

Danny Bonaduce: The selfproclaimed "patriot" and long-time Republican supporter caused a storm when he suggested Jane Fonda, prominent in opposing the invasion of Iraq, should have been shot for treason. On Rosie O'Donnell, who dared to compare the danger posed by radical Christians as akin to the threat of Islamic terrorism, Bonaduce once said: "If anyone had a rope thick enough, I think that Rosie should be strung up for treason."

Howard Stern: Shot to fame in 1985 after NBC sacked him for slipping a sketch into his show entitled 'Bestiality Dial-a-Date'. "I'm sickened by all religions, " he once said. "Religion has divided people.

I don't think there's any difference between the pope wearing a large hat and parading around with a smoking purse and an African painting his face white and praying to a rock."

Opie & Anthony: This pair were responsible for what has been described as the "most vulgar stunt ever broadcast" when they played a live audio broadcast of a couple having sex in the vestibule of St Patrick's Cathedral in Manhattan. Their current favourite stunt is 'Whip 'em out Wednesday', which encourages women to expose their breasts to passers-by, and an 'April Fool' in which they claimed that the mayor of Boston had been killed in a car crash.