Monitoring stations catch a fraction of Fukushima fallout

(Editor: This story has rectified information on how levels of radioactive iodine-131 detected in the air in Canada after Fukushima compared with the Canadian Nuclear Safety Commission’s ceiling for iodine-131. The original story mistakenly said that ceiling was exceeded. We regret the error.)

Confused by all the nuke lingo about becquerels and sieverts and what it means for your health? So were most of the nuclear experts we talked to for this story.

It also doesn’t help that Health Canada’s data on the radioactive fallout from Fukushima is so sparse and confusingly reported that it’s hard to figure out whether or not it exceeds government limits.

Health Canada reports on monitoring data for only three or four of the hundreds of radioactive substances spewing out of the crippled Japanese nuclear plant.

Canada also has only five monitoring stations that contain equipment sensitive enough to notice levels of specific radioactive substances from Fukushima in the air.

“They’re measuring only a fraction of the radioactive fallout from Fukushima,” said Gordon Edwards of the Canadian Coalition for Nuclear Responsibility, speaking from Montreal.

In contrast, the U.S. Environmental Protection Agency has 200 monitoring stations checking for up to 11 radioactive substances in everything from air and milk to drinking water and rainwater.

Health Canada’s radiation-monitoring webpage downplays any fallout concerns, saying radiation reaching Canada has been “within normal background levels”. That’s based largely on data from a second network of 35 other monitoring stations that have less sensitive equipment (including 12 in B.C.).

But an analysis of the data from these stations shows radiation levels did hit sustained above-normal levels for an average of 36 days in March and April after Fukushima. The radiation level rose to 0.48 microsieverts per day, on average, during this time, up from 0.43 seen in the rest of the monitoring data between March 10 and July 27—or an increase of 11 percent.

Of all the B.C. sites, the biggest spike was in Victoria, where the level rose from 0.23 to 0.25 microsieverts per day between March 19 and 25—an increase of 9.9 percent. Vancouver saw a four-percent increase, from 0.43 to 0.45 microsieverts.

The worst-hit city in Canada was Regina. It saw a 90-percent spike in its radiation level, from 0.36 to 0.69 microsieverts per day. Yellowknife was second-highest with a 31-percent jump, followed by Toronto with a 26-percent rise.

But this data downplays the radiation from Fukushima, Edwards said. The less sensitive equipment also picks up large amounts of background radiation from natural sources like the sun and soil.

It also doesn’t spot jumps in the type of radioactive substances released in a nuclear accident, like iodine-131. Another problem: sieverts are a questionable way to measure radiation because they include a subjective calculation of the radiation’s impact on a person, and so the results can be manipulated to play down impacts, Edwards said.

“It’s a shell game. Microsieverts are quite a distance removed from the raw data. They’re blending in stuff from nature to make the data look innocuous,” he says.

You have to scroll down to the bottom of Health Canada’s radiation webpage to find the more striking data from the five stations monitoring specific radioactive substances.

This data shows the air at the five stations showed highly elevated levels of iodine-131 and three other radioactive substances during 30 days on average.

The level of iodine-131 in Sidney, B.C., rose to a high of 3.63 millibecquerels per cubic metre in the air on March 20. That’s over 300 times higher than the background level of 0.01 millibecquerels per cubic metre or less.

The highest level of iodine-131 recorded in the country was in Resolute Bay, Nunavut, where the concentration reached 9.76 millibecquerels per cubic metre. (or nearly 1,000 times higher than the background level).

Also in Sidney, the level of radioactive cesium-137, which has a half-life of 30 years, shot up about 40-fold, from a background level at or below 0.01 millibecquerels per cubic metre to a high of 0.4 millibecquerels per cubic metre on March 25.

Those levels were individually well below the maximum ceilings permitted by the Canadian Nuclear Safety Commission, which for iodine-131 is 200 millibecquerels per cubic metre of exposure in the air on a daily basis for an entire year.

But when all of the radioactive material that was detected is combined together—along with unknown exposure from many other radioactive substances not being monitored by Health Canada, like strontium-90 (which has a half-life of 29 years) and plutonium-239 (with half-life of 24,000 years)—the radiation still poses a health risk as it concentrates and becomes more potent in the food chain, said Gordon Edwards of the Canadian Coalition for Nuclear Responsibility.

“There is no safe level of radiation. What may be acceptable for individual exposure may not be acceptable when millions of people are exposed. It’s important to measure the cumulative impact of all the isotopes, but only a small fraction are being measured,” Edwards said.

Comments

7 Comments

OldGeek

Aug 4, 2011 at 4:35pm

Thank you, Mr Roslin, for such an article. It's long overdue, in my view.

They can mumble about no risk all they want, but when you have thousands of kilos of plutonium-enriched uranium fuel rods sitting around in the open air I'd say there's cause for some concern. And there are thousands of tonnes of unprotected radioactive material at the Fukushima site.

Maybe it's time to reproduce a bit slower, and make our lives and environment healthily sustainable for many generations to come. Much of these problems wouldn't exist if we'd gone with the ZPG thing the UN suggested in the 1970s.

As Robert Heinlein once wrote, it's time to move to a new planet once a license is required for driving around, let alone being burdened by any of the other ills we suffer in our contemporary world.

mike saunders

Aug 5, 2011 at 7:28pm

Here are some facts to put things in perspective.

Natural Background radiation averages 2400 microsieverts per year. Some places on earth like Ramsar Iran, have over 200 times this amount of background radiation without any ill effects on the population. So Regina's 0.33 microsievert per day increase is pretty small. I guess that is why the author has to use the trick of converting the increase to percentages. It sounds so much scarier! Of course even a 100% increase of something insignificant is still insignificant.

If people are that concerned about their health they should stop drinking beer and eating red meat. These are 2 causes of cancer that are actually measurable as opposed to the theoretical unproven increase that 0.33 microsieverts poses.

Gordon Edwards is an idiot for calling sieverts a shell game. Yeah...the shell game called peer reviewed science. Wikipedia has a great article explaining sieverts and it is not too hard to understand. I suggest he read it.

Seriously, the world is on the verge of climate catastrophe that will see hundreds of millions of people die. We need to get off fossil fuels and use every method possible to do so including nuclear power.
If you believe the fear mongering in the Georgia Straight you are being manipulated.
Please do your own research using peer reviewed scientific papers.

Joe Blow

Aug 7, 2011 at 8:59am

The fact that you have a negative rating on your comment mike saunders shows a much more troubling epidemic - and that is the sheep out there that believe everything reporters tell them. I guess this isn't a new phenomenon - Y2K comes to mind. Why is it that people bury their head in the sand when someone tries to speak with a logical, educated mind?

People need to take truth as the authority rather than authority as truth.

Patrick123

Aug 11, 2011 at 6:18am

I'd like to point out how incorrect his use of the millibequerels per cubic metre measurement. If you are allowed 200 millibequerels per cubic metre, per day, for an entire year, you don't scale it down for a shorter time period. You are still allowed 200 millibequerels per day for those 22 days, or whatever time period you want. You are permitted 200 PER DAY, EVERY DAY.

Think of it this way, if you had the 16.7 millibequerel limit per day for 22 days, if you stretch that out for the whole year, you would observe 277 millibequerels, but if you did it with the yearly limit of 200 per day, you would observe 73,000 bequerels. There is no logic behind his shrinking of the limit for a shorter time period.

lisa begg

Aug 31, 2011 at 2:32pm

no matter what the measurements or the levels of background radiation, you cannot dispute that ionizing radioisotopes and particles are here in the Pacific North West air and milk and soil. And the point of the article is that Canada has to implement hundreds if not thousands more of very sensitive ionizing radiation monitors to detect all ionizing radiation particles and ionizing radioactive gases in the environment not only in air but in soil, all types of water, and foods....duh Saunders, do you work for da govament?

Drift Truth

Dec 9, 2012 at 12:22pm

Cover up a melt down for three months , Never mention MOX fuel and then point to back round radiation so fuel flees are a non treat? REALLY?