Did you know granite emits radon?

 
 

Radon Testers, Inc. is offering tests of granite countertops during whole-house radon testing situations.  We want to determine if the granite in indoor applications may emit harmful levels of radon over time.  In 2005, the U.S. Surgeon General issued a national health advisory specifically warning that radon causes lung cancer.


In recent years, the use of granite and other natural stone indoors has increased dramatically.  One should not assume that it is perfectly safe.   The only way to ensure your own home’s granite is safe is to test. 


It has been our experience, though, that people have been more concerned with their kitchen’s granite radon emitting potential than the granite and rock underneath their home (see foundation pictures on this page), which is most assuredly significantly more!  The difference is that we truly live in our kitchens and see that shiny granite.  We can’t see, taste, or smell radon so the thought is hidden away.  Do yourself a favor and test your home for radon gas, but test your kitchen area with granite to see if the ambient air you breathe is safe. 

 

Did you know there can be radon coming from your granite countertop?

  1. 1.Radon (Rn) is an inert gas that results from the decay of uranium in natural stone.

  2. 2.Not only does it emit carcinogenic gases, radon is radioactive.  High levels of radon are found in granite-type igneous rocks where uranium is typically present.

  3. 3.People who work in granite office buildings are exposed to greater amounts of radioactivity than people in other buildings.  If you work in the Thomas Jefferson building in Washington, D.C. (see picture), it will give you an incremental cancer risk 50 times greater than the Super Fund clean up action levels.

  4. 4.Most granite countertops emit only a small amount of radioactivity, but 3-5% can have harmful levels. 

  5. 5.Granite contains trace amounts of uranium and radium, both of which change into radon gas as they decay. 

  6. 6.Granite countertops are, in most cases, emitting mostly gamma radiation.  (see Radiation Health Effects: How Radiation Causes Harm)

     Do You Want to Test Your Kitchen’s Granite?

To do so, we test the kitchen area for radon gas by placing our testing equipment in the breathing zone near or above the granite countertop.  By doing so, we are testing that level of the house for radon gas.  If your countertop is emitting a sizable quantity of radon gas, we will find it.

Should Homeowners Worry About Granite Countertop, Cancer Link?


July 29, 2008


The story broke last week that granite countertops containing uranium (which all granite has in trace amounts) can give off radon, which has been linked to causing cancer.  Radon is the leading cause of lung cancer in non-smokers and second overall.  So with that, should homeowners worry about what is on their countertops?. 


The report was released by the New York Times last week, which stated that “most granite countertops emit gamma, beta and alpha radiation and radon (which is an alpha) at extremely low levels.”


Many medical and radiation experts stated that the amount of radiation and radon given off by the countertops is not high enough to pose any significant risk to people, but definitely some risk.


On the other hand, the Environmental Protection Agency (EPA) has reportedly been talked to by inspectors about granite countertops which do have signifiant levels of radiation and radon being given off.


Granite countertops are a very popular item for homeowners, which makes it no surprise that this would turn into quite a hot topic.


The best thing to do, according to the article, is to find a certified technician who can come in and test your granite countertops.


This may be the only way to ease your mind as a homeowner.

A Report on the Juparana Bordeaux granite countertop in the Houston TV Report

Posted in Granite Radiation by Administrator on the June 16th, 2008


There has been some concern on the Garden Web forum about Bordeaux granites, which ones tend to be high level and which ones tend to be low level. I thought I would share what I have found so far in both informal testing and what little professional testing done so far.


To put things in perspective 10 uR/hr reading at some state recycling centers will be reported to the state radiation control office. Other states like Kansas, allow 25 uR/hr over background radiation (typically 6 to 8 in our area), so a 31 to 33 uR/hr scrap metal will cause alarm. Uranium processing plants being decommissioned must clean the soil till it reaches 5 uR/hr, average radiation level for soil.


Personally, from the last few years research, I set a level of 25 uR/hr over background for the slabs I am willing to let my workers fabricate.


Juparana Bordeaux, shortened to Bordeaux, is one of the ones that MUST be tested prior to purchase. Rarely do you see a Bordeaux below 50 uR/hr Gamma. Much is at 75 to 100 uR/hr. That doesn’t mean you won’t find a low level slab if you go through enough of them.


Crema Bordeaux is one of the lower level Bordeaux. We have tested 5 slabs so far, using the LENi Geiger counter. From 240 to 1500 uR/hr counting Alpha, Beta, Gamma. The fact that there are 240 uR/hr slabs out there shows that one can find lower level slabs. Counting Gamma only, Crema Bordeauxs can run as low as 25 uR/hr, right at our cut off level for safe slabs. Crema Bordeaux did test rather high in the MIA sponsored tests, 292 times more than some of the others, so a Radon detector is a good idea. States sometimes offer them at great deals.


We found one Bordeaux, Golden Bordeaux, that was quite low, 13 uR/hr. Only one slab available for testing, so it doesn’t represent a range, but it is worth looking into if you have your heart set on a Bordeaux.


To put things in perspective on Bordeaux, though, consider the test results on the Houston slab, done by American Radiation Services International . Here is a list of the elements causing it’s radiation.


Potassium 40, 53.9 .

Scandium 46 , 31.65

Colbalt 60 , .13

Caesium137 , .189

Thallium 208, 37.8

Lead 210 , 415.5

Bismuth 212 , 85.46

Bismuth 214 , 410.77

Lead 214, 484.99

Radium 226 , 986.95

Radium 228 , 128.34

Thorium 228 , 144.76

Uranium 235 , 37.83


Total 2,670.196 pCi/g or if you want to compare it in uR/hr, multiply by .95, or 2,337.088 uR/hr.


That slab, in addition to its radiation, one should consider its heavy metal content and the health risks if any.


Potassium is quite harmless, both chemically and it’s decay chain products. It does react with water though, so keeping a granite top dry is always a good idea. The number one reported repair to granite is waterdamage around sinks, according to two companies that repair all types of tops.


Scandium doesn’t seem to have any health effects.


Cobalt 60, yes that Cobalt 60, is another story. Luckily, in this case, the amount in the granite was pretty low. It does produce a dust that is a problem for radiation control. Cobalt 60 has an afinity for Arsenic, another commonly found element in granite, so don’t use granite as a cutting board, don’t roll dough on it.


Caesium is used in atomic clocks, mildly toxic for our discussion because it replaces potassium used in bodily functions.


Thallium is highly toxic, once used in rat poison and insecticides, but banned in the US in 1975. Thallium is also highly water soluable and readily absorbed through the skin. Again it is very close to potassium and can be taken up in the body’s potassium uptake pathways. Thallium has been used as a poisioning agent in murders, although an antidote, Prussian Blue, is available.


Lead needs little explanation, it is a neurotoxin that accumulates in soft tissue and bones.


Radium is taken up by the body as calcium, depositing in the bones and destroying bone marrow. It is a major source of the Gamma radiation in granite.


Thorium produces Thoron gas, which like Radon can decay inside the lungs. Ingestion is the biggest hazard, so again don’t use granite countertops as cutting boards or dough rolling surfaces.


Uranium is both water soluble and acidic liquid soluble, so acidic foods and liquids need to be cleaned up carefully off granite. Uranium is a toxic metal, has been linked to birth defects. Once in the body, it tends to bioaccumulate. Breathing the dust another hazard, of course the Radon that decays out of it is a hazard as well.


The complete lab report on the Juparana Bordeaux granite countertop can be found at the SolidSurfacealliance.org website

PDF Files below of studies, responses etc. 

Granite Countertops: Nuke Your Food Without the Microwave

August 17, 2008. By Gordon Gibb


Lake George, NY: Is your granite countertop radioactive? Chances are good that it is. However, is it harmful? That's the debate that is raging as the health and granite industries lock horns.

The granite countertop has become de rigueur in high-end kitchens as homeowners clamor for the natural esthetics and durability that a granite countertop affords. But in recent weeks media reports revealing the potential for radiation emitting from certain granites has left some homeowners re-thinking their purchase.

In Dr. Lynn Sugarman's case, she ripped those countertops right outta there.

The Teaneck, New Jersey physician purchased her summer home two years ago and was astounded to find elevated levels of radon in the home during a routine inspection. After bringing in a radon measurement and mitigation specialist, the source of the radiation was traced to the countertop in the kitchen. It was reported in the South Florida Sun-Sentinel that Geiger counter readings were ten times higher over the richly grained granite countertop, than elsewhere in the home.

When the technician recommended to Dr. Sugarman that she keep her pregnant daughter, who would be visiting for the weekend, several feet from the countertop to be safe, Sugarman took no chances and had her gorgeous countertops removed that same day, and analyzed at a lab.

Her local Department of Health determined that the granite contained high levels of uranium, which is both radioactive, and releases radon gas as it decays over time. Sugarman admits the health risk to her and her family was probably small, but she didn't want to take any chances.

And therein lay the debate: no one argues that granite has the potential to emit radon gas, or has the propensity to be radioactive. The US Environmental Protection Agency (EPA), and the Marble Institute of America (MIA) admit as much. The bigger question, is just what IS safe? That answer has a lot to do with personal opinion and tolerance, but according to the EPA granite countertops pose no 'significant' health risk.

The key word there is 'significant'.

"While natural minerals such as granite may occasionally emit radon gas, the levels of radon attributable to such sources are not typically high," the EPA statement said. "EPA believes the principal source of radon in homes is soil gas that is drawn indoors through a natural suction process.

"Granite is a natural mineral formed by earth's geology," the statement continues. "It is mined and used to produce commercial products such as countertops. It is possible for any granite sample to contain varying concentrations of uranium that can produce radon gas. Some granite used in countertops may contribute variably to indoor radon levels. However, EPA has no reliable data to conclude that types of granite used in countertops are significantly increasing indoor radon levels.

"Construction materials such as concrete, cinder blocks, bricks, and granite contain small amounts of radioactive materials that are found naturally in the materials used to make them."

Part of the problem may lie in the fact that there are upwards of 900 different varieties of granite available from 63 countries, and the amount of radon, and radiation may depend upon where the granite hails from in the world. Thus, granite itself is less of an issue than the ultimate source.

And it should be noted that there is agreement from health physicists and radiation experts with regard to the extremely low levels of radiation emitted from most granite countertops. However, the EPA found itself in the midst of what has turned out to be the Great Granite Debate after receiving scores of reports from radiation technicians, and from concerned homeowners alarmed at the radiation clicking away the Geiger counter when the instrument was passed over their expensive, imported granite countertop.

Lou Witt is with the EPA's Indoor Environment's Division. He was quoted in the South Florida Sun-Sentinel as saying earlier this month "there is no known safe level of radon, or radiation," he said, adding that scientists agree, "Any exposure increases your health risk."

Whether or not the EPA is softening its stance with a nod to the huge marble industry remains unclear. However, it has been reported that the EPA recommends taking action if radon gas levels in the home exceeds four picocuries per liter of air—which has been identified as carrying the same risk for cancer as smoking a half-pack of cigarettes per day.

In Dr. Sugarman's kitchen, the readings were 100 picocuries per liter.

The debate rages on. "Every time researchers have applied rigorous scientific standards to testing, the results have found that granite countertops pose no risk," says Jim Hogan, President of the MIA. "Repeated studies have found that granite is safe. Unfortunately, some recent junk science being reported as fact only serves to panic the public, not inform it. Our goal is to end this fear mongering by facilitating the creation of a real scientific standard for testing granite countertops."

A recent study by Consumer Reports also concluded that there is no health risk stemming from your granite countertops, and found no radon gas at all released from any of the samples it tested. The specific samples were not identified in the Sun-Sentinel report.

Radon is the second leading cause of lung cancer after smoking and is considered especially dangerous to smokers, whose lungs are already compromised. Children and developing fetuses are vulnerable to radiation, which can cause other forms of cancer.

And beyond that, is the responsibility of those vending the granite, to communicate this fact to their prospective clients. Would most clients be told that purchasing a granite countertop—and an expensive option at that—could raise the radon level in the home? And perhaps more significantly, were the buyer to choose one of the more exotic and striated varieties originating from Brazil and Namibia, he or she could be raising radon levels significantly over other varieties. Brazilian granite is a top-seller.

As the two opposing camps dig in, it will be curious to gauge the response of homeowners with a predisposition to cancer, and an invoice for an expensive granite countertop amongst the rest of the paperwork for their kitchen renovation.

Perhaps it is low risk. But perhaps you would prefer no risk. Perhaps you would have appreciated knowing about this risk beforehand. And perhaps you are now living every moment of your life, afraid to go into the kitchen, but unable financially to make a change. Hell, you might even still be paying for that granite countertop.

Just maybe, a qualified attorney could help you find a way to pay for it…or better yet, get it outta there.

The last word goes to Stanley Liebert. He's the quality assurance director at CMT Laboratories in Clifton Park, New Jersey and the guy who took the radiation measurements in Dr. Sugarman's home.

"It's not that all granite is dangerous," he said. "But I've seen a few that might heat up your Cheerios a little."

 


Probing Question: Could your kitchen counters be radioactive?


Rock of Ages granite quarry Barre Vt. (Barbara Morgan)

Rock of Ages granite quarry, Barre, Vt. (Barbara Morgan)


Verde Butterfly. Black Galaxy. Kashmir Gold. If you’ve remodeled your kitchen in the last decade, chances are you encountered one of the 1,600 varieties of granite imported into the United States from 64 different countries. According to recent market research, demand for natural stone countertops has increased 5 percent annually between 2001 and 2006, with granite being the most popular option. And why not? Granite is not only durable, resistant to mold and mildew, and easy to clean, but because no two pieces of granite are alike, your counter will have its own unique look.


However, over this past summer, several national news stories questioned the presence of radiation and radon emissions from granite. Could the granite counters in your kitchen be radioactive?


Yes, it is possible, though studies to date suggest the risk is relatively low, said Stephen Poterala.


"Granite, as a rock, is prone to having more radioactive metals in it due to the method by which it forms," explained Poterala, a materials science graduate student. "Typically, the uranium and thorium that produce radioactive minerals will crystallize into granite because they don’t crystallize well into other rocks."


As a natural source of radiation, granite contains 10 to 20 parts per million of uranium (as opposed to something like limestone, which contains 1 to 5 parts per million of uranium). So yes, there is a good chance your kitchen countertop will be at least minimally radioactive.


But that's not necessarily a cause for alarm, noted Poterala. Background radiation from many sources in the natural environment is part of our everyday lives. Naturally occurring radiation in the air and soil, from cosmic rays and even from inside our own bodies (from the food we eat) makes up an estimated 80 percent of our total radiation exposure.


In the case of granite countertops, he added, radiation is not the direct health concern; it's radon. "There's a potential that the rock might be releasing radon into the household," he said. Radon is an odorless and colorless gas that is emitted during the natural decay of uranium and, according to the Environmental Protection Agency (EPA), is the second leading cause of lung cancer in the United States, responsible for approximately 20,000 lung cancer deaths annually.


Radiation is measured in units called millirems (mrems), with the average annual dose per person estimated at 360 mrems or 0.04 mrem per hour. According to tests performed on natural stone countertops by W.J. Llope, associate professor of physics at Rice University's Bonner Nuclear Laboratory, most natural stone countertops emitted radiation "at 0.1 to 0.3 mrem per hour," and were "not a significant risk." However, "a handful of samples" emitted 3 to 4 mrem per hour, a rate "the EPA would consider dangerous assuming long-term exposure and would recommend remediation."


The best way to determine that granite is safe to use for countertops, Poterala said, is to scan it before installation in your kitchen using equipment like a Geiger counter or a gamma-ray spectrometer, an instrument for measuring the distribution of intensity of gamma radiation. Unfortunately, in the United States, most granite suppliers don't have the means or facilities for testing granite for radioactivity, and the EPA doesn't regulate granite for radon. At this moment, it's up to the consumer to arrange for their granite to be tested.


If your countertops are already installed, Poterala noted, there are home kits on the market that test for radon. Because radon is a by-product of radioactive materials decaying, "if the radon findings are negative, you can assume you don't have a radiation problem," Llope has said, since radon is a byproduct of radioactive materials decaying. If the results come back positive, you could opt to have the house tested professionally. The American Association of Radon Scientists and Technologists lists the names of qualified professionals who conduct radon and radiation testing on its Web site, http://www.aarst.org. Added Poterala, "If unsafe levels of radon are found in a room of your home, that's when action should be taken."


Even so, that doesn’t mean ripping out those expensive counters. "Usually, to lower radon levels, you need to increase ventilation in the area," Poterala said. That can usually help clear out any radon that has accumulated in the area.


The most important thing, he added, is to not automatically assume granite countertops are unsafe because of a few stories in the media.


"This is not a situation where people should have a knee-jerk reaction and remove their countertops before they understand what’s going on," he said. "Get test results to determine if there really is a hazard."


Source: Research Penn State





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