Response to Sakuramane2004 - ☢ Radioactive Playground Sand ☢

Response to Sakura

☢ Please Read Below Carefully ☢

This is my response to a question posed Sakura asking about the dangers to her daughter from radioactive playground sand. She and her daughter live in Japan and her daughter's preschool sand box was tested and found to have 22 CPM.

Important Notice: I am NOT a physicist or a trained professional or a health care worker. I am an amateur scientist who loves physics and explaining things.

Please seek the advice of a professional if you are worried about radiation and especially if children are involved. I will try to give you some advice (my opinion), but remember to ask your doctor.

That aside, 22 CPM is 8 CPM higher than my background. 22 CPM is about the norm for my bed and less than what a bottle of potassium table salt emits. Most sand and rocks emit small amounts of radiation and I cannot help but wonder if any of that radiation was present before Fukashima. I am not downplaying the events of late. Three meltdowns is the largest nuclear event in history, aside from nuclear weapons, and probably the second most contaminating next to Chernobyl.

Your fears are perfectly normal as a parent, but please consider taking a sand sample to a physicist at a local university or asking your doctor. Determining exposure is VERY tricky and when a child is involved, you don't want to err.


Sieverts cannot be used as a measure unless you know what your measuring. A Sieverts are derived from Grays. 1 Gray is equal to 1 joule of energy deposited into 1 kg of matter. Because some radiation is more deadly than others, and because different parts of the body are affected differently, you must adjust the reading of the dose absorbed by a person to reflect these differences. A dose of 1 mGy (miliGray) of alpha is twenty times more dangerous to a person than 1 mGy of gamma. So, for alpha radiation 1 mGy x 20 = 20 mSv. Sieverts = Grays x radiation_factor x body_part.

My geiger counter is calibrated for Cs137 for gamma only. This means that if I am reading gamma only from a sample of Cs137, I know that 100 CPM = 1 uSv/hr. For an element which produces twice the energy of Cs137, that same 100 CPM would equal 2 uSv/hr. If that element were alpha, it would equal 40 uSv/hr.

Do you see what Sieverts are a bit of a trouble for unknown contamination?

The important thing to do is determine the deviation from normal. Take the Geiger Counter, place it in a neutral area (in your house?) and let it run in the same place for 1 hour. Divide the total count by the time: 1200 Counts / 60 min = 20 CPM. Now, do this in several other places to get a good map of your radiation. You can average them: (reading 1 + 2 +, ..., + n) / n. Now, you can see how high that really is compared to background counts.


If you are worried, have the sand tested again. Ask the person testing what the difference is between that and background.

Category:

Education

Tags:

• children
• radioactive
• fukashima
• japan
• fallout
• sand
• geiger
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• radioactivity
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• uranium
• thorium
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• strontium
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• geigercounters.com
• radiationnetwork.com

[GoddardsJournal]

It's worth noting that there are two types of radiation exposure: Internal and External. Of the two, internal exposure by oral ingestion or inhalation posses greater health risks.

When you say your sofa emits radiation, your exposure is only external. Your sofa shouldn't exposure you to cesium 137 that could find its way inside your body. Risk-assessments that equate internal and external exposure fall short of the required level of concern. And very-young kids will put sand in their mouths.

[antiprotons]

@GoddardsJournal This is totally correct. Breathing in the material is the worst. Injestion is not as bad as much of the material leaves you, but some can still be quite nasty. Uranium can build up in your kidneys and strontium 90 is a bone seaker. The point is to determine if the play sand is above background. if the sand is the same as background, and if the background has not changed since the event, it may be safe. Take it to a university/lab to be sure. For my child, I would.

[mtzlypk]

you just reminded me of what an idiot i am when it comes to equations..anybody that understands this beats me hands down..but i appreciate the effort...oh yes if you were to ask a general physician here in america about radiation , i dont think they would have a clue?i worked with many dr.in er for 6 yrs. and for all you folks that think drs. are idiot proof , you would be wrong.ive met drs. that are drunks,addicts,attrocious bedside manner,and remember theres a top of the class and the bottom!

[antiprotons]

@mtzlypk Well, doctors also claim Tc99m is safe. They send people out into the public emitting 100 to 200 uSv/hr of gamma (tc99m measured by GM referenced to gamma at 661 keV).

Always think for yourself. lol

[edpotkay1]

So if the larger sensor will read 3 times more which one is correct?

[antiprotons]

@edpotkay1 this is why it is so important to understand the device and situation. The GM in saint louis has a probe three times the size of mine, so his 600 CPM rain water would be 200 CPM on mine. Reporting it in mR/hr is no good unless he knows what he is measuring. I often use the sum of the aggregate probabllities of a collectionnof possible elements tmes their energies, divided by their abundance in the set and multiplied by the reading, as a set problem.

[GoddardsJournal]

FYI: there are other radiation monitoring databases in Japan that are much more robust than radiationnetwork. See links in my profile: " Japan radiation mapping "

[edpotkay1]

@antiprotons Ya obviously he was wrong. 60x backround, give me a break. Not sure who that guy is but I am starting to think he is working with duch.. Fear mongering people to get views, a partnership on youtube which in my opinion is WRONG!!!!!!. I am not paranoid by any means, I just want the truth. I think people deserve to know what is going on, and what the long term affects will be

[sakuramane2004]

I don't think I thanked you enough for spending the time to help me out.

thank you. If you come to Japan let me know. I am in yokosuka and you are welcome to stay with us (if my husband oks it or with one of my friends)

[antiprotons]

@edpotkay1 That is the point: they are both correct. If a 1" diameter cup catches 100 drops of water and a 3" diameter cup catches 300 drops, they both caught the same dropsmper square inch of area. The larger contains more water in total. A small scintellator might read 2000 CPM where your GM shows 100. They are both correct. Reading and understanding a GM is more complex than i see many people considering.