This could have been a really good video (below the fold), but it FAILS. One guy sends some samples from Japan to his friend, Tom. It looks like the samples were counted accurately. The highest was about 100,000 Bq/kg (or 2.7 uCi/kg or 2.7 nCi/g).
Now, obviously Fukushima happened. Obviously radioactive cesium has found it's way into the environment (even accumulating under rain spouts, where the hottest sample was found!!!).
Notice that the actual level of radioactivity isn't mentioned in the video, but what is mentioned is that there is "no scientific consensus on the health effects"! Yes, there is consensus!
100,000 Bq/kg is pretty trivial. The risk depends on the exposure pathway which leads to receiving absorbed doses, but unless one works really hard to maximize their dose, it's hard to imagine a realistic exposure pathway, leading to more than a few mrem.
Anyway, I doubt Tom has a radioactive materials license. I saw no mention of it on his website.
Which means he isn't authorized to import or possess byproduct material. And what did he do with the samples?
No, Tom is not a physicist, but...
Hello,
ReplyDeleteYou do not need a license for exempt materials. A sample of 100 kBq kg^-1 is legal if it he actual sample is tiny (say, a few grams). The NRC publishes levels of exempt materials. Additionally, soil samples are not tailings or check sources, etc. they are natural and treated like, for example, a pitchblende sample. The DOT and the USPS all have regulations for these things.
You can mail a finest aware plate and buy a uranium mineral sample on eBay. These are legal without permit. Of course, buying 20 GBq of something would require hazmat trucks, NRC licenses, etc.
Hello
ReplyDeleteYou are correct that one does not need a license for exempt material. However, the concentration was not known until the material was possessed. Unless you can show, prior to receipt, that the concentration is below exemption levels, one has to have a license.
In this particular case, there is no exemption concentration limit for Cs-137 (see 10 CFR 30.70).
Soil samples are natural, but Cs-137 is not. It is considered "byproduct material", meaning it is a byproduct of fission. This is different than pitchblende or uranium.
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ReplyDelete