Explosions and potential meltdowns at Japan's damaged nuclear plants are casting a long cloud over the entire industry, putting a chill on everything from power utilities in Europe to uranium mines in northern Canada.

As engineers and technicians struggle to cool the radioactive cores of three reactors at a power plant north of Tokyo, Switzerland has frozen plans for new plants, uranium mining firms face hard questions about the future and opponents of nuclear power have fuelled growing public protests.

"Europe has to wake up from its Sleeping Beauty slumber" about nuclear safety, Austria's Environment Minister Nikolaus Berlakovich told reporters in Brussels.

He suggested an EU-wide safety test for nuclear plants when the continent's nuclear safety authorities meet Tuesday to assess Europe's preparedness in case of a nuclear emergency.

EU members such as Britain, Bulgaria and Finland have also urged a nuclear safety review.

"The pictures from Japan show us that nothing, even the worst, is unthinkable," said EU Energy Commissioner Guenther Oettinger.

Switzerland has ordered a freeze on new plants or replacements "until safety standards have been carefully reviewed and, if necessary, adapted," Energy Minister Doris Leuthard said.

The German government said it is suspending for three months a decision to extend the life of its nuclear power plants. That also means that two older nuclear power plants will be taken off the grid shortly pending a full safety investigation, Chancellor Angela Merkel told reporters.

Meanwhile, opposition voices rose up in Turkey to renounce or scale back government's nuclear expansion plans. And anti-nuclear groups staged rallies around France, the world's most nuclear-dependent country, as the government sought to reassure the public that the risks remain minimal.

Environmental group Earthlife Africa said it wants South Africa, the only African country with an existing nuclear plant, to follow Germany's example. But South African government officials want to expand nuclear power.

And the continuing bad news from the Japanese nuclear plant sent the stocks of Canadian uranium mining firms plummeting Monday.

Shares in Cameco, the world's largest uranium miner, took a beating on the Toronto Stock Exchange, tumbling 14 per cent.

Fellow Canadian mining company Uranium One was down more than 27 per cent, while Denison Mines Corp. dropped more than 22 per cent.

Cameco Corp. chief executive Jerry Grandey said the drop was "driven by emotion," but said he does not expect Cameco to see significant direct effects in the short or long term.

Some 18 to 20 per cent of Cameco's shipments are bound for Japan, he said, calling the country an "important customer."

While the Japanese emergency may slow the push for more nuclear plants, it appears unlikely to stop it, given the world's fast-growing energy needs.

The governments of Russia, China, Poland and even earthquake-prone Chile say they are sticking to their plans to build more reactors. Spain warned against hasty decisions.

And the Obama administration, which is looking to expand America's nuclear energy industry, said it would learn from the Japanese crisis but said events there would not diminish the United States' commitment to nuclear power.

"It remains a part of the president's overall energy plan," White House spokesman Jay Carney said. "When we talk about reaching a clean energy standard, it is a vital part of that."

Denise Carpenter, president of the Canadian Nuclear Association, told CTV's Power Play that the 9.0-magnitude quake and the tsunami that followed it were unique events and did not reflect the safety standards of the Canadian nuclear power industry.

"We have to remember that Candu reactors are very safe … in Canada for the last 45 years we've run a very, very safe industry," she said.

Carpenter said that more than half of Ontario's power needs and about 15 per cent of the national power grid come from nuclear plants.

"I hope this turns into an opportunity for the industry to have a dialogue with Canadians about how our fuel source is a clean power source," she said. "We have an opportunity to get the facts out there."

According to the International Atomic Energy Agency, there are 442 nuclear reactors in operation worldwide, with 65 new facilities being made.

Construction last year was started on 14 new reactors -- in China, Russia, India, Japan and Brazil. In 2005, in comparison, ground was broken for only three reactors.

Japan, for instance, planned to add 14 plants to the 55 it already had in operation. China has been looking to add 77 facilities to its collection of 13, and India had been looking to more than double its capacity.

"I think they're going to be re-examined, definitely," said Marin Katusa, market strategist with Casey Research in Vancouver. "There's going to be a lot of questions."

While some of the plants may be scrapped, Katusa says he sees many of the nuclear expansions going ahead despite the devastation in Japan.

"They don't have a choice. They may be delayed, but eventually nuclear is a real candidate and all of these countries are trying to increase their energy diversity, and they're trying to grow," he said.

With files from The Associated Press