OTTAWA - An unbowed Stephen Harper is standing by his embattled and unapologetic natural resources minister, dismissing the storm of criticism swirling around Lisa Raitt.

Opposition parties and cancer survivors called for Raitt's resignation - or at least an apology - Tuesday for describing the shortage of isotopes used in cancer tests as a "sexy" issue from which she could benefit politically.

They got neither.

Many were offended by what they described as the minister's cold, selfish, political calculation involving people who are suffering.

"How could she?" gasped Geraldine Owen, 67, of Moncton, N.B., whose daughter-in-law has just begun breast cancer treatment.

"There is nothing sexy about cancer."

The head of the Canadian Association of Nuclear Medicine was also not amused.

"The chronic and acute shortage of medical isotopes is neither a funny nor sexy story," said Dr. Jean-Luc Urbain. "It is a real drama that we have to live with our patients on a daily basis."

But neither Harper nor Raitt were backing down.

"This minister has been working around the clock to make sure we get a greater supply of isotopes and make sure we have alternative options for our health-care patients in this country," Harper told the House of Commons.

"That is what the minister is doing. That is what this government is doing - not playing cheap politics."

That prompted Liberal Leader Michael Ignatieff to fire back: "The cheapest politics there is is to call a crisis a career opportunity."

Raitt, whose brother died of cancer at age 36, said she empathizes with the plight of cancer patients and their families who struggle to support loved ones. But she offered no apology for her remarks made to an aide in January.

She even joined the political counter-attack in the Commons, saying when it comes to the isotope crisis "the only people interested in political opportunism is the opposition."

Her controversial comments came in a five-hour recording that was made Jan. 30 and obtained by the Halifax Chronicle Herald after a Raitt aide misplaced her tape recorder.

The aide, Jasmine MacDonnell, resigned last last week after it was revealed that sensitive documents about the future of Atomic Energy of Canada Ltd. were mistakenly left behind at a TV news bureau for a week following an interview.

In the tape, Raitt says the isotope issue is hard to control, "because it's confusing to a lot of people."

She then adds: "But it's sexy. ... Radioactive leaks. Cancer."

She also expresses doubts about the parliamentary skills of Health Minister Leona Aglukkaq.

Regardless of whether it was a private conversation, Owen said it's clear Raitt was putting her "own power and ego above her compassion and humanity."

NDP Leader Jack Layton and Bloc Quebecois chief Gilles Duceppe said the public is scandalized by Raitt's attitude.

"A lot of us in this House are surprised and shocked that there hasn't at least been an apology," Layton said. "Not only is she losing secret documents, but she expected a career bounce as a result of a medical crisis."

Last week, the rookie minister from Toronto faced calls for her resignation after news of the misplaced AECL documents broke.

She has also come under fire for $80,000 in travel and hospitality expenses rung up in two years in her former job as CEO of the Toronto Port Authority.

The government got more bad news Tuesday with the sobering revelation that smaller hospitals across the country will run out of medical isotopes by Thursday, leaving many cancer and heart patients scrambling to find alternatives.

Throughout a relentless series of attacks in the Commons, Raitt calmly outlined the steps the government has been taking to resolve the isotope shortage, caused by the emergency shutdown of the AECL reactor at Chalk River, Ont.

But it didn't placate angry cancer survivors and relatives whose loved ones were struck down by the disease, many of whom flooded radio talk shows demanding Raitt resign or be fired.

"This is outrageous and I think she should be gone, right now," said Tina Titus, 39, of Dartmouth, N.S., who helped nurse her best friend through breast cancer.

"This hurts people. I watched my friend go through chemotherapy and I was with her when she went through that. When I went through this with her she was sick all of the time. She couldn't get out of bed. There's nothing - absolutely nothing - sexy about that."

Norma Fisher, 87, who has survived two bouts of cancer in Kemptville, Ont., said at the very least the minister should issue a public apology.

"I'm trying to be fair, but most people realize the trauma that people go through when they have cancer and are sensitive to it," said Fisher, who helps counsel 40 others who are battling the disease.

In her lonmg taped chat with MacDonnell, Raitt discusses Aglukkaq's handling of the isotope shortage.

"They're Terrified Of The Issues," Raitt Says During The Recording.

"You know what? Good. Because when we win on this, we get all the credit. I'm ready to roll the dice on this. This is an easy one. You know what solves this problem? Money. And if it's just about money, we'll figure it out. It's not a moral issue."

Raitt says she is disappointed in Aglukkaq.

"Oh, God, she's such a capable woman, but it's hard for her to come out of a co-operative government into this rough-and-tumble. She had a question in the House yesterday, or two days ago, that planked. I really hope she never gets anything hot."

Raitt praised Aglukkaq in the Commons on Tuesday.

The tape was made public only after a Halifax court hearing which rejected MacDonnell's bid to keep it secret. Her lawyer argued that the recording was made inadvertently and that the conversation was supposed to be private.

The Nova Scotia judge in the case ruled that it was in the public interest to release the recordings.

"It is wrong to deprive the press, and the public it serves, of remarks made privately but not confidentially in the sense of trade secrets," said Justice Gerald Moir.