Miniscule concentrations of isotopes of cesium, iodine and tellurium in local water

Are you still concerned about radiation crossing the Pacific from the crippled Fukushima nuclear plant in Japan, despite the steady stream of scientific advice that it poses no danger?

Now you can check radiation readings from right here in Berkeley, thanks to the monitors that the Department of Nuclear Engineering has on the roof of Etcheverry Hall. A team of scientists working under Kai Vetter is testing air and water quality (from rainwater) every day.

What are the results?

Unless you are the most irrational worrier in Berkeley, there’s nothing to be worried about. Although the measurements are in the standard Becquerels per liter, the Berkeley team helpfully translates the data into more understandable terms. For air quality, the unit they choose is the number of years of breathing the air that would be needed for a person to receive the radiation exposure of a single round trip flight from San Francisco to Washington, D.C. On Monday the worst result was for a radioactive isotope of iodine (I-131): it would take 858 years of breathing the amount measured in Berkeley to equal that plane flight. At the peak measurement, last Friday, it would have required 168 years to equal the flight exposure.

Water quality is equally unalarming. Again, I-131 has the worst result: on Monday’s data, you’d need to drink 1,734 liters of water to equal the radiation dose from a single round-trip flight to Washington, D.C, and back. At the peak measurement, last Friday, you’d need to drink 134 liters to equal the flight exposure.

The scientists also tested water from Strawberry Creek. The results were 10 to 50 times lower than the rain water results. Finally, locally bought milk was also tested. The milk produced higher concentrations of radioactive iodine than the creek water, but lower than rain water. Around 3,800 liters of milk would be required to equal the radiation of one round-trip flight to Washington.

Lance Knobel

Lance Knobel (co-founder) has been a journalist for nearly 40 years. Much of his career was in business journalism. He was editor-in-chief of both Management Today, the leading business magazine in Britain,...

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  1. I’ve been shopping for Geiger Counters as well. Trying to find a newish Alpha/Beta/Gamma/x-ray counter is fairly difficult. Especially on a budget.
    Don’t be fooled by some of the older Dosimeters/ Survey meters. They don’t all read Alpha/Beta waves. Further the Geiger tube is pretty fragile and most on ebay are untested w/o warranty. Others on ebay say they won’t ship until end of April or May, what good is that? By then it will be too late..

    Still, in the meantime I’m stocking up on canned tuna and cheese. The milk won’t keep long enough so I’m just not buying any, not to mention it’s probably too late to get “clean” milk anyway.. The rice milk is a good sub anyway.

    Good luck folks. Don’t get dosed!

  2. I’m very bothered by the way the American press is handling this. Go to Google and search (like I just did) “radiation” “rain water”. Now click on News on the left side of the screen and something like “last 24 hours” or “last week”…. Now, scan down the page of search results and compare superlative terminology to diminutive terminology. There are virtually no terms used like “heavy concentrations” but all of the adjectives associated with “nothing to see here, don’t worry, be happy” are there.

    There’s “minimal”, “minuscule”, “tiny amounts” while any of those stories, such as the rain water in Berkley can be searched individually to narrow the disinformation cloud and we see things like “Rain water in Berkley, CA measured 181 x the legal limit for drinking water”.

    Where does rain go? Where does “drinking water” come from?

    But mostly, when the local and / or federal governments say that radioactive milk is safe for babies when non-pasteurized milk is not I start shopping for a Geiger counter.

    “No immediate danger to health in humans?” Why did the word “immediate” need to be included if everything’s cool?

  3. The U.S. Department of Energy testified in court that there is no level of radiation without health risks. “The U.S. Department of Energy has testified that there is no level of radiation that is so low that it is without health risks,” Jacqueline Cabasso, the Executive Director of the Western States Legal Foundation

    The UCB Nuclear Engineering Department says that “any exposure to these radionuclides in California would be for a short time (days or weeks at most).” Are they psychics now, too? We are almost at a month with no sign of it stopping, so they are completely wrong with that assumption. Why in the world would they suggest such a thing? TEPCO just implied that it might be years…

  4. Exposure defined by Google, vulnerability to the elements; to the action of heat or cold or wind or rain; “exposure to the weather” or “they died from exposure”.
    That relates to all external sources I think. Actually taking the element internally, I think would fall into a different category, probably much worse.
    All I know is, I’m swearing off seafood for a few years.. And cows milk for a shorter term, maybe a few months..
    I hope that helps some..

  5. I am not understanding your response to Aaron’s question.
    How exactly is one getting exposed to I-131 on a plane flight – that’s talking about external radiation exposure (from Iodine???) – as compared with breathing I-131 in and the thyroid’s taking it up? I still do not get this. It sounds like apples and oranges.

    Can you or someone say more???

  6. I am totally with you with your question and I do not understand how Brian has answered it.
    How exactly is one getting exposed to I-131 on a plane flight – we’re talking about external radiation exposure – as compared with breathing it in and the thyroid’s taking it up? I still do not get this.

    Can someone say more???

  7. Of course I was being a bit tongue in cheek, but if you look at the whole saga of this tragedy, as soon as the authorities assured us everything was fine and under control, they’d have an explosion, radiation leak, fire, or some other kind of emergency. They would then reassure us everything is fine now, only to be followed by more catastrophes. Sorry, but I have to be skeptical when I hear these words of reassurance.

  8. Yes. the exposures are cumulative – that’s the biggest point here. Comparing the exposure to what you get on a plane flight may provide a relatively accurate dose calibration, but it implies that you’ll get one dose or the other. When you get them both, along with whatever other doses you’re getting, what’s the total body load over time? And what can we do with all the spent fuel from electricity we’ve already used? It will be toxic for a while longer – say 200,000 years. Nowhere on Earth to put it. I heard one nuclear engineer at a technical conference suggest we could ship it on rockets and send it into the sun. As long as the rocket doesn’t explode.

  9. Aaron, The key word is ‘exposure’, which is incorrectly used by Knobel. The people at Cal compared radioactive doses, which takes into account the fact that consuming a radioactive material induces a larger dose for a given radioactivity than external irradiation.

  10. Isn’t it more about inhaling or consuming the actual physical element of I-131, rather than exposure to gamma, or beta rays which are emitted from the isotope? You relate the exposure to a plane flight, but on an airplane you aren’t actually consuming the element, you’re getting exposed to the rays. I-131 accumulates in the thyroid, the radiation from I-131 passes through you, like all background radiation. Am I right here??

  11. The thing is that radiation is cumulative. So in order to understand the actual impact, we need to add the exposure from air, water, food to the rates we’re already getting. To suggest that this is ‘no big deal’ is missing the point that the reason it’s ‘no big deal’ is because we’ve already done such tremendous and profound damage to our environment by releasing ridiculous amounts of radiation into our ecosystem through decades of nuclear testing and imbecile accidents (did you know that the worst nuclear accidents were on submarines?).

    This is very much like saying ‘well… we have dumped tons of chemicals into the river already, so a little more won’t hurt things’ except the chemicals are cumulative, and we have no idea where we will reach a tipping point where the ecosystem simply cannot process more of our waste and trash.

    The good news about the Japan situation is that this is likely to put a cap on nuclear energy permanently. Slowing the damn thing down by a decade or two should give us enough time to switch to renewable sources — and countries like Germany are leading the way. We need to put a permanent stop to fossil fuels and nuclear – before they put a permanent stop on us.