Design

Published on January 24th, 2009 | by Linda Kincaid, MPH, CIH

38

Granite Counters: Uranium Ore In Disguise?

January 24th, 2009 by  


Cathy Woods’ new granite counters were radioactive. They contained as much uranium as commercial uranium ore. The showroom that sold Cathy her Jupurana Bordeaux granite did not warn her that some granite is radioactive.

When I contacted the salesman, posing as a customer, he assured me their granite “is no more radioactive than soil or water”. However, Cathy’s granite emitted gamma radiation at many times background. The radon gas emitted by the stone tripled the radon concentration in her kitchen.

Jupurana Bordeaux is one of the granites that are likely to be radioactive. Just weeks after having her counters installed, Cathy learned of the possibility and enlisted the assistance of professionals to assess her exposure to radiation and radon gas.

Radon is a daughter product of uranium, so granites containing uranium will emit radon. According to the EPA, radon is the leading cause of lung cancer in non-smokers. Cathy and her husband both have family histories of cancer, so they were very concerned about elevated radiation and radon in their kitchen.

Some granite quarries are near uranium mines. Most granite does not contain large amounts of uranium, but some granite can have more uranium than a homeowner would want in the home. Cathy and I measured radiation from about 1,000 slabs of granite in showrooms around the San Francisco Bay Area. Most of the granite was only slightly radioactive. However, a small percentage emitted gamma radiation (penetrating radiation) at many times background.

We found Jupurana Bordeaux emitting gamma radiation at nearly 100 times background in the very showroom that claimed none of their stone was radioactive. When Cathy confronted the owner about his granite, he said he had no intention of warning buyers.

Cathy fell in love with Volga Blue granite to replace her Jupurana Bordeaux. It is mostly black with shiny crystals and iridescent “blue eyes”. Gamma emission was barely above background, one of the least radioactive granites we had seen.

We were left with many questions about radioactive granite we saw in showrooms. How much radioactive granite is installed in homes? How many of those homes have young children or pregnant women? Why don’t granite showrooms warn their customers?


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  • David Landry

    Thanksfor the heads-up. It sure would be helpful to know which granites are the most offending and have them listed in this blog or at least given some reference elsewhere on the net.
    D.L.

  • David Landry

    Thanksfor the heads-up. It sure would be helpful to know which granites are the most offending and have them listed in this blog or at least given some reference elsewhere on the net.
    D.L.

  • Sweden had a big radon scandal in the late seventies when it was discovered that many newly built multiappartment houses was radioactive due to the concrete. I’m not sure if the awareness have survived, but some building material was made illegal (“blåbetong” ie. blue concrete).

  • Sweden had a big radon scandal in the late seventies when it was discovered that many newly built multiappartment houses was radioactive due to the concrete. I’m not sure if the awareness have survived, but some building material was made illegal (“blåbetong” ie. blue concrete).

  • David,

    The problem with making a list is that granite types that we thought to be 100% low level will have a slab show up at increased levels. Then again, the hottest slab types aren’t all hot, there are some low level slabs.

    Making a list of granites to watch would stigmatize some granite types and make people somewhat complacent about other types. In the end, all slabs should be tested for radiation and Radon prior to purchase if we want to lower the risks.

    The stone industry has recently bowed to the inevitable and has started advocating a testing program for their fabricators and slab importers to follow. While this is a positive step forward, few are likely to trust anyone other than an independent tester, too much money at stake, too much health risk possible if chicanery occurs.

  • David,

    The problem with making a list is that granite types that we thought to be 100% low level will have a slab show up at increased levels. Then again, the hottest slab types aren’t all hot, there are some low level slabs.

    Making a list of granites to watch would stigmatize some granite types and make people somewhat complacent about other types. In the end, all slabs should be tested for radiation and Radon prior to purchase if we want to lower the risks.

    The stone industry has recently bowed to the inevitable and has started advocating a testing program for their fabricators and slab importers to follow. While this is a positive step forward, few are likely to trust anyone other than an independent tester, too much money at stake, too much health risk possible if chicanery occurs.

  • Pingback: Hostile Granite Showrooms Refuse to Discuss Radiation : Green Building Elements()

  • Tim

    What I want to know is what is the acceptable level of radon? Is the level recorded in this material above the “safe” level established by whoever decides this stuff?
    EPA maybe?

  • Tim,

    The EPA “action level” for radon is 4 pCi/L. That radon concentration is measured in a home, not in the stone itself. Different granites emit different amounts of radon. Different homes have different amounts of ventilation. The only way to know the radon concentration in a given home is to do a radon test.

    Some granites emit several hundred pCi/hr of radon from each square foot. The amount of radon in the home will depend on the amount of granite and the amount of ventilation in the home.

  • Tim,

    The EPA “action level” for radon is 4 pCi/L. That radon concentration is measured in a home, not in the stone itself. Different granites emit different amounts of radon. Different homes have different amounts of ventilation. The only way to know the radon concentration in a given home is to do a radon test.

    Some granites emit several hundred pCi/hr of radon from each square foot. The amount of radon in the home will depend on the amount of granite and the amount of ventilation in the home.

  • Pingback: California Real Estate Agents Provide Misinformation about Radon : Green Building Elements()

  • Pingback: Lung Cancer Victims Blame Radon: Call Government Policy a “Deadly and Impotent Failure” : Green Building Elements()

  • Alex

    To be very blunt with everyone who thinks this article is actually worth reading, if you really think there is enough uranium ore in your counter tops to actually effect your health??, maybe you should think twice before going out in the sun without sun screen, or think before you put your cell phone to your head! or better yet, throw away your microwaves!! you are so worried about something as natural as granite, and yet you dont look at the things in your life that could actually do you harm!..granite is going to have traces of uranium BECAUSE ITS NATURAL! you cant expect to have the beauty of granite and not expect that natural elements such as uranium or very small percentages of radioactivity are not going to be present! It just wont happen!, and if you cant accept that, dont put granite in your houses, its that simple. No one is forcing you to buy granite. Unfortunatley thats the risk everyone has to take when you purchase this stuff. Its not enough to hurt you, and if you think youd rather not take the chance, then dont, cause trust me, theres just someone else to replace your business at these showrooms. happy hunting!

  • Alex

    To be very blunt with everyone who thinks this article is actually worth reading, if you really think there is enough uranium ore in your counter tops to actually effect your health??, maybe you should think twice before going out in the sun without sun screen, or think before you put your cell phone to your head! or better yet, throw away your microwaves!! you are so worried about something as natural as granite, and yet you dont look at the things in your life that could actually do you harm!..granite is going to have traces of uranium BECAUSE ITS NATURAL! you cant expect to have the beauty of granite and not expect that natural elements such as uranium or very small percentages of radioactivity are not going to be present! It just wont happen!, and if you cant accept that, dont put granite in your houses, its that simple. No one is forcing you to buy granite. Unfortunatley thats the risk everyone has to take when you purchase this stuff. Its not enough to hurt you, and if you think youd rather not take the chance, then dont, cause trust me, theres just someone else to replace your business at these showrooms. happy hunting!

  • How funny! Alex’s post is almost identical to one that “Terri” posted on another of this author’s articles.

    Terri, AKA Alex,

    There you go, once again ranting about the sun (UV radiation) and cell phones and microwaves (both electromagnetic radiation), proving to all, once again, that your are incredibly ignorant of the article and facts on the issues.

    It isn’t so much that consumers are stupid, as your post seems to portray. It is that people such as yourself have lied about the issue for the past 15 years. Do a simple google search using “granite countertop radiation radon” and watch hundreds of stone websites pop up that deny the issues are real. Had the consumers known that their granite could contain large amounts of uranium or other radioactive elements, few would purchase same.

    Here is a fine example of the double talk within your own post.

    “Unfortunatley (sic) thats the risk everyone has to take when you purchase this stuff. Its not enough to hurt you, and if you think youd rather not take the chance”

    First you claim that there is a risk everyone has to take when purchasing granite, then you claim there isn’t anything there to hurt you? Why is there a risk if there is nothing there to hurt you? You go on to claim there is a ” chance”, which one would consider referring to the risk you refer to from buying granite.

    “cause trust me, theres just someone else to replace your business at these showrooms.”

    So, what you are saying is that if you are concerned about the potential for radiation or Radon gas coming from granite, not to bother coming to your showroom? That there are plenty of other customers that will take your place?

    What a fine business model, depending on your customers to be ignorant enough to not question the safety of your product.

    Terri/AKA Alex, as one poster wrote a few weeks ago, there will be a special place in Hell for the likes of you.

  • How funny! Alex’s post is almost identical to one that “Terri” posted on another of this author’s articles.

    Terri, AKA Alex,

    There you go, once again ranting about the sun (UV radiation) and cell phones and microwaves (both electromagnetic radiation), proving to all, once again, that your are incredibly ignorant of the article and facts on the issues.

    It isn’t so much that consumers are stupid, as your post seems to portray. It is that people such as yourself have lied about the issue for the past 15 years. Do a simple google search using “granite countertop radiation radon” and watch hundreds of stone websites pop up that deny the issues are real. Had the consumers known that their granite could contain large amounts of uranium or other radioactive elements, few would purchase same.

    Here is a fine example of the double talk within your own post.

    “Unfortunatley (sic) thats the risk everyone has to take when you purchase this stuff. Its not enough to hurt you, and if you think youd rather not take the chance”

    First you claim that there is a risk everyone has to take when purchasing granite, then you claim there isn’t anything there to hurt you? Why is there a risk if there is nothing there to hurt you? You go on to claim there is a ” chance”, which one would consider referring to the risk you refer to from buying granite.

    “cause trust me, theres just someone else to replace your business at these showrooms.”

    So, what you are saying is that if you are concerned about the potential for radiation or Radon gas coming from granite, not to bother coming to your showroom? That there are plenty of other customers that will take your place?

    What a fine business model, depending on your customers to be ignorant enough to not question the safety of your product.

    Terri/AKA Alex, as one poster wrote a few weeks ago, there will be a special place in Hell for the likes of you.

  • How funny! Alex’s post is almost identical to one that “Terri” posted on another of this author’s articles.

    Terri, AKA Alex,

    There you go, once again ranting about the sun (UV radiation) and cell phones and microwaves (both electromagnetic radiation), proving to all, once again, that your are incredibly ignorant of the article and facts on the issues.

    It isn’t so much that consumers are stupid, as your post seems to portray. It is that people such as yourself have lied about the issue for the past 15 years. Do a simple google search using “granite countertop radiation radon” and watch hundreds of stone websites pop up that deny the issues are real. Had the consumers known that their granite could contain large amounts of uranium or other radioactive elements, few would purchase same.

    Here is a fine example of the double talk within your own post.

    “Unfortunatley (sic) thats the risk everyone has to take when you purchase this stuff. Its not enough to hurt you, and if you think youd rather not take the chance”

    First you claim that there is a risk everyone has to take when purchasing granite, then you claim there isn’t anything there to hurt you? Why is there a risk if there is nothing there to hurt you? You go on to claim there is a ” chance”, which one would consider referring to the risk you refer to from buying granite.

    “cause trust me, theres just someone else to replace your business at these showrooms.”

    So, what you are saying is that if you are concerned about the potential for radiation or Radon gas coming from granite, not to bother coming to your showroom? That there are plenty of other customers that will take your place?

    What a fine business model, depending on your customers to be ignorant enough to not question the safety of your product.

    Terri/AKA Alex, as one poster wrote a few weeks ago, there will be a special place in Hell for the likes of you.

  • Oh, I had better exlain to Terri/Alex about the (sic) addition to your quote. I wasn’t commenting about mental or health issues, I was marking the spelling in the comment as being exactly as you wrote it.

  • Oh, I had better exlain to Terri/Alex about the (sic) addition to your quote. I wasn’t commenting about mental or health issues, I was marking the spelling in the comment as being exactly as you wrote it.

  • Exlain?? Explain… how funny.

  • Exlain?? Explain… how funny.

  • Pingback: Free Testing for Homes with Exotic Granite : Green Building Elements()

  • Tim

    HI Again,
    I haven’t had time to check back lately.

    So I understand correctly the amount of radiation emitted is what is of concern.
    “The EPA “action level” for radon is 4 pCi/L.” This is airborne levels when measured however it is measured, right?

    “Some granites emit several hundred pCi/hr of radon from each square foot” What does this translate into an airborne level.

    In my reading I have found that water levels translates to 10000pCi/L in water to 1pCi/L in air.
    http://www.bae.ncsu.edu/programs/extension/publicat/wqwm/he396.html
    Is there an effective way to determine the effect “xxx pCi/L” in each square foot of granite will have in my home?
    Or even better since we cant determine variables like ventilation, Is it possible to determine how much granite it would take in a sealed room of xxx sqft emitting xxx pCi/L to make it surpass the standard of 4pCi/L airborne.
    Thanks in advance!
    Tim

  • Tim

    HI Again,
    I haven’t had time to check back lately.

    So I understand correctly the amount of radiation emitted is what is of concern.
    “The EPA “action level” for radon is 4 pCi/L.” This is airborne levels when measured however it is measured, right?

    “Some granites emit several hundred pCi/hr of radon from each square foot” What does this translate into an airborne level.

    In my reading I have found that water levels translates to 10000pCi/L in water to 1pCi/L in air.
    http://www.bae.ncsu.edu/programs/extension/publicat/wqwm/he396.html
    Is there an effective way to determine the effect “xxx pCi/L” in each square foot of granite will have in my home?
    Or even better since we cant determine variables like ventilation, Is it possible to determine how much granite it would take in a sealed room of xxx sqft emitting xxx pCi/L to make it surpass the standard of 4pCi/L airborne.
    Thanks in advance!
    Tim

  • Tim

    HI Again,
    I haven’t had time to check back lately.

    So I understand correctly the amount of radiation emitted is what is of concern.
    “The EPA “action level” for radon is 4 pCi/L.” This is airborne levels when measured however it is measured, right?

    “Some granites emit several hundred pCi/hr of radon from each square foot” What does this translate into an airborne level.

    In my reading I have found that water levels translates to 10000pCi/L in water to 1pCi/L in air.
    http://www.bae.ncsu.edu/programs/extension/publicat/wqwm/he396.html
    Is there an effective way to determine the effect “xxx pCi/L” in each square foot of granite will have in my home?
    Or even better since we cant determine variables like ventilation, Is it possible to determine how much granite it would take in a sealed room of xxx sqft emitting xxx pCi/L to make it surpass the standard of 4pCi/L airborne.
    Thanks in advance!
    Tim

  • Tim,
    those are good questions.

    4 pCi/L is the airborne level that the EPA recomends action at. However, the EPA bases their 21,000 radon deaths per year in the U.S. at only 1.3 pCi/L, so that tells you that there is no safe level of radon. Congress stated that the long term goal is to reduce radon to outdoor air levels, .40 pCi/L.

    An effective way to test your granite would require setting a meter under an accumulator (we use aquarium tanks) on every square foot of your granite, but the bottom of the granite usually puts out more than the polished top. I ran a test yesterday, got almost 10 times more radon from the bottom accumulator than the top accumulator. It would be easiest to close off the room the kitchen is in, then do a CO2 test alongside a radon test for 48 hours to get the amount of radon coming off the stone.

    We have a radon room running, 36 square feet of low radiation (26 uR/hr average radiation per 3″ square grid, just 1 uR/hr over our maximum allowed radiation level for fabrication) can put the room over 30 pCi/L in just a day if the weather is calm. We then used forced ventilation, 90 liters per minute (.22 ACH meaning the air was changed out completely every 4 to 5 hours) and the radon fluctuates between 2 and 4 pCi/L during a 48 hour test. That .22 ACH is about average for a newer home, not a super tight energy efficient home though and not an older, leaky home.

    XXX pci/L of radon risk? The EPA used to say that 8 pCi/L is like smoking a pack a day. Turns out it is a bit more complicated, but that is a way of explaining things that is both simple and effective.

  • Tim,
    those are good questions.

    4 pCi/L is the airborne level that the EPA recomends action at. However, the EPA bases their 21,000 radon deaths per year in the U.S. at only 1.3 pCi/L, so that tells you that there is no safe level of radon. Congress stated that the long term goal is to reduce radon to outdoor air levels, .40 pCi/L.

    An effective way to test your granite would require setting a meter under an accumulator (we use aquarium tanks) on every square foot of your granite, but the bottom of the granite usually puts out more than the polished top. I ran a test yesterday, got almost 10 times more radon from the bottom accumulator than the top accumulator. It would be easiest to close off the room the kitchen is in, then do a CO2 test alongside a radon test for 48 hours to get the amount of radon coming off the stone.

    We have a radon room running, 36 square feet of low radiation (26 uR/hr average radiation per 3″ square grid, just 1 uR/hr over our maximum allowed radiation level for fabrication) can put the room over 30 pCi/L in just a day if the weather is calm. We then used forced ventilation, 90 liters per minute (.22 ACH meaning the air was changed out completely every 4 to 5 hours) and the radon fluctuates between 2 and 4 pCi/L during a 48 hour test. That .22 ACH is about average for a newer home, not a super tight energy efficient home though and not an older, leaky home.

    XXX pci/L of radon risk? The EPA used to say that 8 pCi/L is like smoking a pack a day. Turns out it is a bit more complicated, but that is a way of explaining things that is both simple and effective.

  • Tim,
    those are good questions.

    4 pCi/L is the airborne level that the EPA recomends action at. However, the EPA bases their 21,000 radon deaths per year in the U.S. at only 1.3 pCi/L, so that tells you that there is no safe level of radon. Congress stated that the long term goal is to reduce radon to outdoor air levels, .40 pCi/L.

    An effective way to test your granite would require setting a meter under an accumulator (we use aquarium tanks) on every square foot of your granite, but the bottom of the granite usually puts out more than the polished top. I ran a test yesterday, got almost 10 times more radon from the bottom accumulator than the top accumulator. It would be easiest to close off the room the kitchen is in, then do a CO2 test alongside a radon test for 48 hours to get the amount of radon coming off the stone.

    We have a radon room running, 36 square feet of low radiation (26 uR/hr average radiation per 3″ square grid, just 1 uR/hr over our maximum allowed radiation level for fabrication) can put the room over 30 pCi/L in just a day if the weather is calm. We then used forced ventilation, 90 liters per minute (.22 ACH meaning the air was changed out completely every 4 to 5 hours) and the radon fluctuates between 2 and 4 pCi/L during a 48 hour test. That .22 ACH is about average for a newer home, not a super tight energy efficient home though and not an older, leaky home.

    XXX pci/L of radon risk? The EPA used to say that 8 pCi/L is like smoking a pack a day. Turns out it is a bit more complicated, but that is a way of explaining things that is both simple and effective.

  • Great article. Thank You!

  • Great article. Thank You!

  • Great article. Thank You!

  • goldbaron357

    As a prospector who has spent a day running up and down a mountain range looking for rock outcrops besides granite hoping to find gold, I can tell you that if there is uranium to be found, it is found in Granite. In all the rock outcrops I found in the area I was at, all the outcrops were granite, and all carried uranium ore, to the extent of having been commercially mined in the past.

    So it should be no surprise to get radioactive counter tops when having granite brought in… If you want a chance for gold or silver instead, go for slate…

  • goldbaron357

    As a prospector who has spent a day running up and down a mountain range looking for rock outcrops besides granite hoping to find gold, I can tell you that if there is uranium to be found, it is found in Granite. In all the rock outcrops I found in the area I was at, all the outcrops were granite, and all carried uranium ore, to the extent of having been commercially mined in the past.

    So it should be no surprise to get radioactive counter tops when having granite brought in… If you want a chance for gold or silver instead, go for slate…

  • Joe

    Sounds like stainless steel countertops should be alot more popular. S/S is a true green and recyclable product (and there are no health issues).

    Joe

  • Joe

    Sounds like stainless steel countertops should be alot more popular. S/S is a true green and recyclable product (and there are no health issues).

    Joe

  • Who still believe in that the granite countertops contain radon that can cause cancer? This is PR tricks from other countertops companies, people, open your eyes.

  • RK

    As for the testing I find great fault in the testing methods as well as released data. Off-gassing, as it relates to measurable levels in cut granite slabs, begins as soon as the granite is extracted from the ground because it is officially being pulled from the source where the uranium resides – the earth as opposed to when still in the ground uranium is a constant source going into the granite right? (if that makes sense)

    So, once extracted from the earth, what is the rate at which this off-gassing depletes? Or would this be measured more in terms of a 1/2 life? What is the time frame from mining to showroom floor/ fabricator typically, if importing from abroad? And if in fact the off-gassing reduces over any given period of time, as I would assume because it is no longer associated with the gas source (uranium) then wouldn’t the amount of time from mining to installation show lower off-gassing levels?

    Is the granite shipped in an open air container or is it sealed tight? Wouldn’t this factor in the reading of the radon level because there would be potentially no place for the gas to escape to?
    Then what is the total life cycle of the radon emissions in granite ie. what would the levels of radon be in a 20 year old piece of granite as used for a countertop vs. a one month old granite countertop?

    Then several articles reference uranium mines by the granite mines? And most of what I have read infers that because uranium is being mined that hence forth the granite is more corrupted by this. When in fact the uranium is occurring naturally in the earth. And is it safe to assume that the uranium on some level is contributing to the coloration and patterning of the granite (I’m sure other gasses contribute as well – true?)

    If it is true that the polished surface reports lower levels of off-gassing then wouldn’t it be prudent to polish the entire piece of granite?

    And if the off gassing levels do in fact reduce over time then wouldn’t it make sense to at least in the wake of this highly debated issue – cut the granite, test it and if the levels are to high store it in highly ventilated spaces until such time as the off-gassing levels show a respectable reduction? Costly I am sure but would be an option.

    Finally, as the EPA has made a general focus on out door air quality over indoor then what is the EPA’s findings on the Uranium levels at these granite mines once the granite is exposed; as these are very large quarries. I would imagine this would clearly be an issue to the immediate surrounding land and air quality/ And for any countries or companies over the mining regulations who would be concerned then I am sure they would want to monitor the risk of cancer in their employees (however this might be a far fetched statement as most places where granite is mined, outside of the US, really have little to no workplace safety regulations nor are they bothered with providing health care)

    Would love some truly educated feedback on my questions.
    Thanks!

  • I don’t think so that stainless steel counter-tops should be more familiar in the market. But i have heard that laminate counter-tops are still demanding by all the homeowners.
    Kitchen

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