Activated carbon and I-131/132
Is activated carbon filtering at the point source of usage an effective method of removing/reducing trace elements of (specifically) I-131 and I-132 in tap water?
BTW, thank you for all of your efforts and this forum.
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Testing activate charcoal filters
As this forum is at the homepage of nuc berkely I wonder if someone could make an experiment to evaluate the effect of activated charcoal as a filter for radioactive iodine and cesium.
Britta japan clearly states on their homepage that their filters do NOT filter radioactive iodine and cesium. However, the Japanese competitor teraoka claim on their homepage that they have filter that can remove radioactive material from water, I don't believe this statement. I also don't believe what I found at http://www.freedrinkingwater.com/japan-hope-water.htm because the given links to us sites showed no clear scientific results but only general statements.
I further don't trust Japanese official measurements in respect to statements "not detectable level" because I found information that this is defined by different official organizations in different ways.
Thus, I am coming back to my question if someone from nuc berkely could please be so kind as to make some scientifically soundm tests. People living in japan would be VERY grateful for reliable test results.
HEPA
I'm not an expert in water filtration but if you wanted to filter radionuclides from air you would use a HEPA filter, though I have my doubts as to how effective it would be for such small particles. A filter that is designed for removing particulate might work better than activated carbon. Perhaps reverse osmosis or distillation?
Anyway the danger of having iodine radionuclides in California tap water from the Fukushima mess is vanishingly small. It takes most of a half life for it to get to us across the Pacific. Then it has to get through the ground and into a reservoir (which could take months), through the pipes, through the water treatment plant (which on it's own is very effective at removing particulate from the water) then through more pipes before it ever comes out of your tap. We are talking about dozens, maybe hundreds of half lives in the very fastest possible path from Japan into our drinking water.
To see how a half life works, take a packet of sugar and pour it on the table. Use a credit card to divide it in half. Then divide one of those in half, and the divide one of those piles in half, etc. How many half lives do you go through before you are left with a single grain? (It took me 15.)
I live in Tokyo and I am in
I live in Tokyo and I am in the States right now. I'm wondering if BRITTA water filters with activated charcoal would filter out iodine 131 and 137.
reply
Why do people who aren't experts and who don't know the answers to things provide answers?
Please check the team
Please check the team website. JMiller is a team member here and researches these answers quite thoroughly.
Reference to published research is what's needed
Instead of speculation, how about a citation for a published scientific study? (I'm trying hard to find such info.) I live in Japan, in an area where I-131 and Cs-137 have been detected in rainwater and in produce. The concern is that our drinking water will also soon be affected. However, the local government is not testing the tap water in our city. Understandably, those of us living here would really like to know for certain if a specific type of filtering (reverse osmosis? activated charcoal?) is effective at removing I-131 and Cs-137, and, if so, to what degree each method is effective. The health of people, especially young children, may be affected by the long-term ingestion of even low doses of radioactive isotopes, so having correct answers backed by published scientific data -- not speculative opinions -- is what we need. Thanks!
Removal of isotopes, Chernobyl fall-out, H2O Treatment
Sorry you're in such a bind. It must be frightening.
Based on the difference between rainwater and Strawberry Creek runoff, plus the evidence in multiple papers on soil testing after Chernobyl, I'd feel fairly safe drinking water the Japanese authorities say is safe AFTER I filtered it through a nice thick layer of sand and clay finished off with activated charcoal.
I don't have time for a full search but a quickie picks up these:
The first link is a pdf, where on the page labeled 18 I found references to a couple of other articles:
http://www.port.ac.uk/departments/academic/sees/research/environmentalmo...
"A critical review of measures to reduce radioactive doses from drinking water and consumption of freshwater foodstuffs"
J.T. Smitha,*, O.V. Voitsekhovitchb, L. H(akansonc, J. Hiltona
a Winfrith Technology Centre, Centre for Ecology & Hydrology, Dorchester, Dorset DT2 8ZD, UK
b Ukrainian Hydrometeorological Institute, Nauka Ave. 37, Kiev 252028, Ukraine
c Institute of Earth Sciences, University of Uppsala, Norbyv . agen 18-b, 75236 Uppsala, Sweden
This review mentions flocculation, sand filtration, activated charcoal and zeolite as being effective.
An article that might be helpful; here's the link but if it's not accessible the title is below and can be searched. I don't know what access is available outside of a university library. There is also a reference list at the end of the review for further search.
http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B6V73-4888D84-1...
"Removal of the typical isotopes of the chernobyl fall-out by conventional water treatment"
R. Goossensa, A. Delvillea, J. Genota, R. Halleuxa and W.J. Masscheleina
a Laboratories of the Brussels Water Board, Chaussée de Waterloo 764, B-1180 Brussels, Belgium
Received 1 January 1988;
accepted 1 January 1989.
Available online 31 March 2003.
Abstract
A classical full-scale treatment scheme including coagulation-flocculation-upflow settling and rapid sand filtration is investigated for its efficiency in removal of trace concentrations of radioactivity, demonstrated by four isotopes. Known activity of each isotope is added to the raw water and a mass balance is established by measuring the activities in the sludge and in the treated water. Maximum removal efficiencies found were: 73, 61, 17 and 56% for 103Ru, 58Co, 131I and 134Cs accordingly.
I looked into the published
I looked into the published articles on pubmed for reverse osmosis and did not find much with respect to filtration of iodine. With respect to activated charcoal, I did find the following article (Appl Radiat Isot. 2009 Oct;67(10):1748-50. Epub 2009 Apr 8. A simple and rapid technique for radiochemical separation of iodine radionuclides from irradiated tellurium using an activated charcoal column.), which when I pulled up the actual article, they were acidifying the solution first (to a pH of 1-3 with HCl), then 99% of the iodine 131 was absorbed by the activated charcoal, then poured a hot NaOH solution over the activated charcoal to recover 75-85% of the iodine.
Please note, I am not sure how effective iodine filtration by activated charcoal is at typical tap water pH, and adding HCl & NaOH to your water may be more detrimental to your health than the iodine-131 (or even perhaps alter your own absorption and storage of it.) Also, if you are using an older activated charcoal filter, you may be releasing previously absorbed compounds such as heavy metals and organic compounds. Food for thought.
Here is an article about
Here is an article about removing radioactive contaminants from drinking water that you may find helpful.
http://foodfreedom.wordpress.com/2011/04/26/how-to-remove-radioactive-io...