In a story airing tonight at 11 p.m., the I-Team looks at all the recent buzz about granite and radon.

 

Just weeks after we installed new granite countertops in our home this summer, I read the NY Times article about radon exposure from granite countertops.

 

I got this sick feeling in the pit of my stomach.

 

So I started researching.  And I was surprised to find that granite and radon concerns are specifically addressed on the California Department of Public Health website.

 

I admit that I felt betrayed…I’m a journalist, I’m a concerned parent and research all manner of things, yet I had never heard about radon emitting from granite.  All I had to do was type in an internet search on granite and radon, and all manner of material popped up.  Why wasn’t this more widely known?

 

Radon is the number one cause of lung cancer in non-smokers.  The National Cancer Institute  has a good question and answer article about radon and cancer.

 

Then I wanted to know if I really needed to worry about the granite countertops sitting in my home.  I don’t care about what studies found in other homes…what about these specific slabs of granite…which I would figure would be unique. 

 

The short answer to that question is: maybe.

 

How did I get that answer?  Even the agencies and experts who have since come out as saying that the risks are being exaggerated admit that some granite could emit higher than normal levels of radon. 

 

The EPA website says:

Some granite used for countertops may contribute variably to indoor radon levels.  At this time, however, EPA does not believe sufficient data exist to conclude that the types of granite commonly used in countertops are significantly increasing indoor radon levels. Some granite may emit gamma radiation above typical background levels.  While radiation levels are not typically high, measurement of specific samples may reveal higher than expected levels on a case-by-case basis.

 

The Health Physics Society sent a letter to the NY Times shortly after the article was published, saying that the measured radon level from the granite countertop featured in the story was not valid and highly improbable.  Even so, they also said:

 

It isn’t a surprise that some granite emits radiation. So do other items in our households. The amount of radiation emitted from granite can vary depending on the amount of natural uranium and/or thorium concentration.

 

The U.S. Geological Survey says this about uranium, the ultimate source of radon:

Some types of rocks have higher than average uranium contents. These include light-colored volcanic rocks, granites, dark shales, sedimentary rocks that contain phosphate, and metamorphic rocks derived from these rocks. These rocks and their soils may contain as much as 100 ppm uranium. Layers of these rocks underlie various parts of the United States.

 

So it seems the consensus is that every granite slab will be different.  There could be granite slabs with higher than normal uranium or thorium, which could then lead to higher than normal radon emissions.

 

Even within one slab of granite, there could be one part of it with little uranium and another part with more uranium.  It’s not identical throughout. 

 

You can’t tell by looking at a granite slab or granite tiles if it’s emitting too much radon.  You can’t tell by its country of origin. Once it’s in your home, how it contributes to the overall indoor radon emissions will be affected by factors such as: the size of the home, the amount of granite, whether the granite is sealed or not, the flow between outside and inside air, etc.

 

The best thing for a concerned homeowner to do is to test your indoor radon levels.  That’s because the ultimate concern is whether the overall radon levels in your home are dangerous.  There are different ways to test, but the simplest method can be done inexpensively and easily and in a short period of time.  I’ll have more on testing later.

 

It’s even a good idea to test a home if there is no granite in it.  According to the EPA, one out of 15 homes in the U.S. has elevated radon levels.

 

Radon is everywhere because it primarily comes from the soil (the EPA website has a good overview on radon).  So everyone is exposed to radon, but it becomes a problem when you’re exposed to too much radon.  And there are areas where the radon concentrations can be high:  inside a building for instance.

 

Darioush Ghahremani, Ph.D. of Radon Survey Systems, Inc. in San Diego is a California certified radon tester.  He’s studied radon issues for years.  He explains that any home anywhere could possibly have a problem with indoor radon levels.  Some homes are more susceptible than others…homes on an earthquake fault for instance.  The U.S. Geological Survey lists some of the other factors here.

 

HOW TO DO A SHORT-TERM TEST

Here’s the simple way:  buy a short-term radon test kit and do it yourself.  These are charcoal canisters that you put in your home for at least 48 hours, then seal and mail to a specified lab and wait for the results.

 

You may wonder, like I did, which brand to buy.  Are they all reliable?  Unfortunately, they are not.

 

Lucky for us, the good folks at Consumer Reports released a report in August where they tested seven brands of short-term radon test kits (they have recommendations for long-term tests as well, which they say are more reliable).  Of those seven charcoal canisters, they could only recommend one:  the RTCA charcoal canisters at $19.95 each.

 

I bought three of the RTCA canisters online (that’s the only way) and used the California Department of Public Health testing instructions.

 

Also, although they were not one of the brands tested by Consumer Reports, the California Department of Public Health has $5 charcoal canisters available for California residents.

 

When I received the results of the canister test, all three canisters measured radon levels of 0.2 picocuries per liter of air (pCi/L)….which is good.  Consumer Reports suggested testing with another method if the results are 2 pCi/L or more.  The purpose of having three readings is that if the one nearest the granite countertops is higher than the others, then that could indicate more radon coming from the granite.

 

Another way to test is to call a California certified radon tester.  The list of certified testers is on the California Department of Public Health website.

 

 Dr. Ghahremani has a few different methods of testing available for consumers, including the company’s own charcoal canisters. 

 

The typical instrument Dr. Ghahremani uses for short-term testing is a continuous radon monitor.  These devices are more sensitive and more accurate than the charcoal canisters.  The cost for this type of testing is generally between $150 and $250.

 

Dr. Ghahremani, in the end, used two different continuous radon monitors at my house on two different occasions.  The first one he used at the same time as the charcoal canister test.  It took a reading every hour for the course of the two-day test and then printed out the results, and provided an average reading.  The average radon level was 1.3 pCi/L. 

 

Because of the difference between the canister readings of 0.2 pCi/L and the continuous radon monitor’s 1.3 pCi/L, Dr. Ghahremani did one more two-day test with another continuous radon monitor (perhaps there was some kind of electronic interference with the machine that read 1.3 pCi/L).  This one measured not only the radon level every hour, but also the temperature, relative humidity and barometric pressure.  The average radon reading with this device was 0.3 pCi/L.

 

The reason for all the multiple tests?  We wanted to see for ourselves if the charcoal canisters from RTCA were indeed reliable.  They seem to be.

 

If you have the time, long-term radon testing is available from a variety of sources and is an accurate way of testing.  Some long-term tests take 90 days.

 

What if your test results are high?  There are ways to lower the radon levels without ripping out granite, if that is your concern. 

 

ARE THERE SAFE LEVELS OF RADON EMISSIONS?

Now here’s what I don’t like:  blanket statements that granite countertops pose no health risk.  That’s what the Marble Institute of America keeps insisting.  The MIA represents the natural stone industry so I understand why they are pushing that message.

 

Even the EPA says this:

However, EPA believes that any radon exposure carries some risk – no level of radon is safe. Even radon levels below 4 pCi/L pose some risk, and you can reduce your risk of lung cancer by lowering your radon level.

 

The EPA says you need to take action if your indoor radon levels are 4 pCi/L or higher, but they also say you may want to consider doing something about levels between 2 and 4 pCi/L.  Smokers, children and pregnant women are especially susceptible to the harmful effects of radon exposure.

 

Let consumers determine for themselves what level of risk they can tolerate.  Lead in crystal is an example.  People know that ingesting lead is harmful.  They know that lead is in crystal.  But Proposition 65 warns consumers about the risks and lets them decide whether or not they want to buy it. 

 

Likewise, some people may not mind a little more radon from granite if the overall level is still low.  Others may not want to introduce any additional radon into their home.

 

But give people the chance to make an educated decision…notify them, tell them.  And notify them at the places where they buy granite.