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Posts Tagged ‘radiation’

Build Your Own Cloud Chamber!

September 14, 2011 Leave a comment

Cloud chambers are nifty little tools which physicists used in the 1920s to 1950s to study ionizing radiation. They were responsible for the discovery of the positron in 1932, which garnered Carl David Anderson the Nobel Prize in Physics in 1936.

After the 1950s, the Bubble chamber became the more useful tool to study radiation, but cloud chambers remain the simplest and easiest to build.

In fact, you can even build one yourself! Here’s a cool video demonstrating how they work and how you can build one:

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Please Don’t Build a Cellphone Tower Because We’re “Afraid of the Unknown”

May 23, 2011 3 comments
File:Cell Phone Tower.jpg

Photo by Joe Ravi

The CBC reports that residents of Surrey and Port Coquitlam, BC are petitioning against the construction of two new cell phone towers in the area.

There is a proposal on the table to build two cell phone towers in the area of Cloverdale, as people often complain of losing their cell phone signal in this area.

Some residents oppose the construction mainly due to fear of health effects from the radiation emitted by the towers.

The CBC interviewed a Coquitlam resident, Andrea Gretchev, and asked what she thought the tower construction would do and why she opposed its construction,

“I can’t say that this causes anything in particular, because I don’t know,” Gretchev said. “But because I don’t know, I don’t want to live next to a cell tower.”

Fear of the unknown is a natural human response and I can’t begrudge the residents this natural instinct.

But for comparison, lets look at the situation of me being afraid of the dark when I was a child.

I was afraid of the dark because I didn’t know what was out there. I was afraid of the unknown. As soon as my Dad turned the light off, there could be monsters, or aliens, or giant-ass bugs waiting to attack me.

Periodically, I would race to the light-switch and turn on the light, exposing everything in the room to electromagnetic radiation (in the visible range, of course).

At once, I realized nothing was there. I was safe. I didn’t have to be afraid anymore.

Eventually, I learned that there really was nothing to fear when the lights went out. Just because I couldn’t see the rest of my room, didn’t mean I had to be afraid of it.

So is there a similar “light-switch” in this situation that we can flip on so the residents of southern British Columbia don’t have to be afraid of cell phone radiation anymore? Why yes there is. And its scientific data.

Seeing as I’ve written on this issue many, many times before, I won’t rehash all my past arguments. But the scientific data is quite clear that there is absolutely no credible evidence that cell phone radiation causes adverse health effects.

You would think that this information would be enough, but I’ve had enough experience debating this issue that I know this is not nearly enough.

“Science has been wrong before,” is the counter-argument I most often hear.

“Well,” I reply, ” should we then also be afraid of broccoli?”

“What do you mean?” my opponent asks.

“Science has shown that broccoli is quite healthy for us. But if science has been wrong before, should we therefore avoid broccoli completely? Just in case?”

So when debating the issues, lets stick to the facts and not logical fallacies.

I know its tough. There are a lot of quacks out there trying to convince us that cell phones and power lines and Wi-Fi are dangerous, in complete opposition to all of the credible scientific evidence.

Hell, if you do a Google search for any of these topics, no doubt you will find more fear-mongering websites talking about the “possible” dangers with electromagnetic fields than references to scientifically valid papers.

Scientists may not have the Search Engine Optimization teams that these fringe websites do, but they have the truth on their side. And the truth continues to indicate that we have no reason to fear our phones.

Still not convinced? Have a look at this map showing all the cell phone towers in the lower British Columbia area (also available as an iPhone app):

Map of all cellular phone towers in the lower British Columbia area.

In this sea of towers already in existence, and all those near your house that you have been living peacefully beside for the past several years, will two more really make a difference?

More than that, with the explosion of cell phone use and cell tower construction in the last decade, isn’t is odd that no increase in cancer rates have been seen?

We should have at least seen a small effect by now if there were any health risks associated with these towers or cell phone use.

But again, I’ve had this argument enough to know that data and common sense won’t convince anybody. Anything new and widespread will inevitably cause people to be afraid. Much like microwave ovens did in the 1950s and 60s.

By the way, no adverse health effects have ever been reported with the proper use of a microwave oven. I guess we will have to wait about 60 years before people will start chilling out about their cell phones.

Ontario Opposition Parties Resort to Radiation Fear Mongering

April 13, 2011 Leave a comment

Ontario Premier Dalton McGuinty was criticized for not releasing details of increased radiation levels in Ontario. - Photo: Joshua Sherurcij

It keeps happening, and it keeps blowing my mind.

However, this time it is not the media that is the culprit of radiation fear-mongering, but the opposition parties in the Ontario provincial government.

A story today from The Globe and Mail details how Premier Dalton McGuinty and the provincial Liberal party have come

under fire from opposition members on Wednesday for failing to tell the public about elevated levels of radiation detected in the province following Japan’s nuclear disaster.

The problem with this though, is that the increased radiation levels in Ontario are negligible.

I wrote a post a few weeks ago about increased radiation levels being detected in British Columbia, on the west coast of Canada. The media, of course, jumped all over the story, even though the increase in radiation detected was less than the increase seen when it rains.

And it rains A LOT in BC.

The increase seen in Ontario is even smaller. In fact, as Leslie Meerburg, spokeswoman for Health Canada, pointed out:

A five-hour airplane flight from Montreal to Vancouver exposes an individual to 50,000 times more radiation than the level detected in Canada as a result of the earthquake in Japan

Let me give you some more numbers to show you just how ridiculous this complaint by the opposition parties really is.

Radiation dose absorbed in a biological system is calculated in units of Sieverts (Sv). This unit takes into account the radiation type, amount of radiation absorbed by your body, as well as the sensitivity of various organs to radiation exposure.

On average, you get about 10 micro-Sieverts (1.0 x 10-5 Sv) of radiation dose per day. That five-hour flight from Montreal to Vancouver gives you about 40 micro-Sieverts (4.0 x 10-5 Sv).

The increased amount of radiation in Ontario is roughly 0.00008 micro-Sieverts (8.0 x 10-10 Sv).

This is an increase of about 0.0008 %.

Need a visual? Here is a bar graph comparing a normal day’s worth of radiation dose in Ontario, compared to a day with the “increased levels” of radiation dose.

In other words, there is absolutely no danger associated with this increased level of radiation.

So why did the NDP give the Liberals a hard time?

New Democrats questioned government ministers for the second straight day on why they have not been more transparent with the public by publishing information on radiation levels in the air, water and food supply.

“This government totally dropped the ball,” NDP Leader Andrea Horwath said in Question Period.

I generally support the NDP, but it was the NDP in this case that dropped the ball. I’m very disappointed by this.

Turns out, the Ontario government had already increased testing all food, milk and water in the wake of the Japan nuclear crisis. The NDP was upset that they didn’t tell anybody.

But I feel this was the right call. Why cause undo fear and panic  when there is absolutely no danger? I’m glad the government increased their testing rates, just to be on the safe side, but telling the public would have been a mistake.

Refusing to understand the science behind an issue and using fear to further a political agenda is distasteful and shows a lack of judgment. Frankly, it is something more akin to American politics.

Fukushima Q & A With Physicists

April 12, 2011 Leave a comment

Last week, Nature magazine held a live Q & A about the Fukushima nuclear power plant disaster in Japan. Understandably, people had many questions about the actual dangers associated with the damaged reactor.

The session included Jim Smith, an environmental physicist from the University of Portsmouth, U.K., and Geoff Brumfiel, Nature’s senior physical sciences correspondent.

With all the media hoopla, which included getting the science flat-out wrong and over-blowing the dangers (or lack thereof) here in North America.

Scientific American wrote a brief excerpt of the interview here. You can also get the full transcript on the Nature website.

Here’s an example of the kind of questions that were asked, and the answers given.

[Question From ZoeyZoey: ] Although there are high levels of Cesium 137 and Iodine 131 in the water around Japan many people believe that it is not cause for concern because of the ocean’s ability to vastly dilute what is put in it. Do you believe other countries should be concerned or do you agree that the ocean can fix it?

Jim Smith: Yes, there is enormous dilution of radioactivity in the marine system. By the time any contamination got across the ocean to other countries (if any did), the concentrations would be tiny and wouldn’t present any risk. The concern for the marine system is mainly in the local area to Fukushima.

 

Nuclear Fission Explained…With Skittles and Mouse Traps

March 24, 2011 Leave a comment

Thanks to Pharyngula for posting this. Awesome!

Radiation From Japan Reaches Canada. RUN! PANIC! AAAAAH!

March 22, 2011 2 comments

File:Radiation symbol alternate.svgOne day, I think I’m going to open up a news website or newspaper and there is going to be a front page headline that reads “LOOK OUT BEHIND YOU!”.

This is getting ridiculous.

New outlets, including CBC, ran an article today and yesterday about increasing radiation levels detected in Canada and in Iceland. The cause of this radiation is attributed to the crisis with the nuclear power plant in Japan. So just how big of an increase in radiation was there in British Columbia?

Gary Holub says increased radiation levels were expected, and are less than the increase in radiation levels Canadians would see naturally when it rains.

Holub stressed that the increase poses no health risk to Canadians.

Seriously? Less of an increase than when it rains? Yet the CBC chose to run a headline which said: “Increased Radiation Detected by B.C. Monitors“.

Scientific American reported what the U.S. Energy Department and the Environmental Protection Agency had to say about the increase in radiation.

They said the radiation amounted to one-millionth of the dose rate that a person normally receives from natural sources such as rocks, bricks and the sun.

This increased level of radiation is not even newsworthy, let alone worthy of a scaaaaaaaary headline. Everyone on this side of the pacific ocean has nothing to worry about.

Actually, unless you are one of the heroic Japanese workers trying to restore power to the nuclear plant, you have very little to worry about.

Does nobody remember that there were victims of an earthquake AND tsunami in Japan recently? Are we only paying attention to the nuclear plant now because news outlets love the fear generated by the word “radiation”?

Donations to the Japanese relief effort can be made through The Canadian Red Cross

Other places to make donations can be found here.

Relative Radiation

March 21, 2011 Leave a comment

With the current crisis in Japan with the nuclear power plant, the media has latched onto the public’s fears of radiation.

And y’know what? I understand that fear. Radiation is invisible. It could be anywhere and you won’t know it until it’s too late.

But I am not afraid. Why?

The thing is that I know how much radiation we get on a daily basis, and how it compares with certain medical procedures and working near radiation sources, like a nuclear power plant. Most people do not, and the media plays on those fears to drive up ratings.

Thankfully, Randall Munroe of xkcd fame has created another wonderful (and timely) poster illustrating the relative doses associated with doing certain tasks or living near certain places.

Click on the image see the large version.

Some of the most interesting comparisons:

  • You get more than 3 times the radiation dose living within 50 miles of a coal power plant than you do living within 50 miles of a nuclear power plant
  • Flying round-trip from New York to Los Angeles would give you the equivalent dose of living within 10 miles of the Three Mile Island accident.
  • Living in a stone, brick, or concrete building for 15 years gives you a larger radiation dose than anyone got from the Three Mile Island accident.
  • Using a CRT monitor for a year gives you a larger radiation dose than living next to a nuclear power plant for a year (but then again, who uses CRT monitors anymore?)

So while the Japan nuclear crisis is indeed serious, it is no reason to stop using nuclear power in general.

Oh, and the radiation dose from cell phones is zero, because phones don’t generate ionizing radiation and they don’t cause cancer. Relax, people.

Some Unexpected Stuff From Japan’s Nuclear Crisis

March 15, 2011 Leave a comment

As Japanese officials are attempting to cool the reactors at the Fukushima Daiichi nuclear plant, which was damaged after the devastating earthquake and ensuing tsunami last week, some unexpected things have been happening as a result of the fear from this situation.

In an effort to help Japan conserve its electricity, game developers Konami and Square Enix will be suspending online access of their games to Japanese consumers for the time being.

Square Enix operates MMORPG games Final Fantasy XI and Final Fantasy XIV, and Konami operates Metal Gear Online.

How much electricity this will actually save is a difficult question to answer, but in times of crisis I suppose that every little bit helps.

In another development, Germany has temporarily shut down 7 of its nuclear power plants.

“We want to look at the risk and safety issues in the light of events in Japan,” the European energy commissioner Guenther Oettinger said.

While I can understand the desire for safety, particularly in light of the media-driven fear of radiation contaminating the rest of the world, I think this action is not only an over-reaction, but it adds fuel to the fire of radiation fears.

This also comes in the face of a massive anti-nuclear protest in Germany, which was already planned prior to the devastation in Japan,

Protesters in Stuttgart formed a human chain reaching 45km (27 miles) for the event, which had been planned before the current nuclear crisis in Japan because it was already a key election issue.

Switzerland has also suspended decisions on its current nuclear power structure to re-evaluate its country’s energy plans.

This is quite baffling to me because nuclear energy is one of the cleanest and safest forms of energy production. It is not exactly fair to use the Japan situation as a case against nuclear power, seeing as it was recently hit by and 9.0 magnitude earthquake AND a tsunami.

The Japanese crisis is indeed serious, but unique. It actually wasn’t the earthquake or the tsunami which directly caused the explosions. It was an unfortunate failure of the backup power systems to the power plant which prevented cooling water from circulating, which then caused overheating and eventually an explosion.

So I don’t believe that blaming the nuclear boogeyman is the right way to react to this scenario. Disasters do happen and there are unforeseeable consequences. And as I write this, the containment structures of the reactor cores have not yet been breached, and the Japanese are attempting to cool them by flooding the structures with seawater.

Much like the Three Mile Island scare, the potential for damage is there, but no large amounts of radiation have been released yet.

Unfortunately, solar and geothermal power are not quite ready to meet the world’s energy needs yet. Wind power is starting to be criticized because of its environmental impact. So for the time being, nuclear power remains our best bet for environmentally conscious energy production.

Cell Phones, Your Brain, and the Media

February 23, 2011 72 comments

Usually, when a scientific study gets this much media attention, it has something quite impactful to report.

But when the study has nice, media-friendly buzz-words like “radiation” and “brain activity”, you get a firestorm of media coverage. Even if your study doesn’t say all that much.

The study I am referring to is called “Effects of Cell Phone Radiofrequency Signal Exposure on Brain Glucose Metabolism” which was recently published in the Journal of the American Medical Association.

The study looked at 47 healthy volunteers; a relatively small study. The researchers took these volunteers and gave them all PET scans on their brains. They had also strapped two cellphones on either side of their head. One cell phone was on, and the other was turned off.

During a 50 minute phone call, they compared the two sides of their brain to see if there was any change in glucose uptake.

What did they find?

Whole-brain metabolism did not differ between on and off conditions. In contrast, metabolism in the region closest to the antenna (orbitofrontal cortex and temporal pole) was significantly higher for on than off conditions (35.7 vs 33.3 μmol/100 g per minute; mean difference, 2.4 [95% confidence interval, 0.67-4.2]; P = .004). The increases were significantly correlated with the estimated electromagnetic field amplitudes both for absolute metabolism (R = 0.95,P < .001) and normalized metabolism (R = 0.89; P < .001). [JAMA]

So basically, whole-brain metabolism was the same whether the phone was on or off. However, in regions close to the phone’s antenna, the metabolism was “significantly higher”. It is important to point out that in this context, “significantly” means statistical significance, not a large increase. In fact, the increase was only about 7%.

Brain imaging physicist Dardo Tomasi of Brookhaven National Laboratory, who co-authored the study, said that’s several times less activity than visual brain regions show during an engaging movie. [Wired]

Ok, so now the important question: what does this mean for our health? Nora Volkow, the study’s lead author commented:

Volkow says it is too early to tell whether this is good or bad for the brain. “Much larger fluctuations in brain activity occur naturally,” says Patrick Haggard at University College London. In fact, being able to increase activity might boost the brain’s connectivity, and could even be useful therapeutically, Volkow suggests. [New Scientist]

So although the study was published as a “Preliminary Communication”, and that the study itself concludes:

This finding is of unknown clinical significance. [JAMA] (emphasis mine)

there is still a large number of news outlets which reported on the study. Why?

Well we know why already. That “unknown” word in the above quote carries a lot of baggage.

Cell phones are the new danger to health, of course. Despite there being no conclusive evidence that cell phones even have the ability to cause cancer, and the fact that even with the explosion of cell phone use in recent years, cancer rates have not increased, people are still scared of their cell phone.

This is thanks to poor media coverage, and a few crackpots out there who are determined to prove that technology is going to destroy us all.

And as a result this small, preliminary study with a result that, while interesting, is completely benign, gets extensive media coverage. Not only that, but some news sites give thinly veiled comments suggesting that the results somehow show that cell phones are dangerous, like this one:

The unusual finding, published on Tuesday in the Journal of the American Medical Association, is likely to lead to new calls for stricter regulation of radiation emissions from the ubiquitous phones. The government currently assumes the signals have no effects other than a harmless warming of tissues near where they’re held. [The Globe and Mail]

or this one:

Some studies have linked cell phone exposure to an increased risk of brain cancers, but a large study by the World Health Organization was inconclusive. [MSNBC]

Of course they used the word “inconclusive” in the above quote, when it should really read “it showed no correlation”. Scicurious points out that this is probably because “‘inconclusive’ sounds scarier”.

So nobody panic. This study does not show that cell phones are dangerous. It may show that the electric field from the antenna somehow increases metabolism of glucose, but those findings need to be corroborated by other labs. Let’s wait until their findings are duplicated on a larger scale and a mechanism by which this effect happens can be discovered before we decide what, if any, impact this study should have.

Do Cell Phone Towers Make Women Pregnant?

December 23, 2010 3 comments

A Typical Cell Phone Tower, via Wikimedia Commons.

That is what the data is showing.

Using publically available data on the birth rates of communities, Matt Parker, who writes for The Guardian, did an analysis of the data and found this remarkable correlation. On average, there were 17.6 more babies born above the national average in the area around a cell phone tower.

So are cell phone towers actually causing women to get pregnant?

No.

And that’s the point.

On his blog, Parker is trying to make the point that correlation does not equal causation, which is almost a mantra for skeptics. Recent hysteria regarding WiFi and Cell phones has prompted many skeptics (including yours truly) to blog on the subject and express their displeasure. Not only with the quack “scientists” promoting this idea, but also with the media for callously reporting on it without proper research, only furthering the spread of misinformation.

Parker says,

There is no causal link between the masts and the births despite the strong correlation. Both the number of mobile phone transmitters and the number of live births are linked to a third, independent factor: the local population size. As the population of an area goes up, so do both the number of mobile phone users and the number people giving birth.

This is what is known as an observational study. The study is not performed in a lab where variables can be controlled. It is performed by observing the real world and attempting to make sense of the data.

As you can see, it is quite easy to come to a false conclusion despite good data. Accounting for all variables in such a study is extremely difficult, and sometimes damn near impossible. Firm conclusions on a topic should never be drawn based solely on a study of this type.

It should go without saying, but there is no credible evidence linking wireless internet or cell phone use to health problems. This is junk science promoted by junk scientists, and spread through the naive media who care more about ratings and readers than reporting truth.

I really like that someone took the time to get make this point using real data. Hopefully, this will get as many headlines as stories about cell phones causing cancer do.