Advice provided by: Dr. Mitch Kennedy, LEED AP, Design with Nature, LLC
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Hi Kirstin,

You may have read the New York Times article on radon in Granite countertops, or you may have heard from a neighbor that granite is bad for your health. In this brief response, I hope to clarify the issue and offer you options.

Most research performed on granite, and its radiation risk to workers and consumers over the past 10 years, fails to list the trade names of the stones tested (for example Ubatuba). Also, due to its popularity, there are now over 600 varieties of beautiful granite available, and within a single type, some samples may be more radioactive than others.

In August, 2008 the New Jersey Department of Environmental Protection's Radon Program clarified it’s position on testing countertops in kitchen environments. Their advice is that kitchens should not be tested because humidity, temperature changes, and exhaust systems can impact test conditions. They suggest an area adjacent to the kitchen and that test kits be allowed free access to the air, not be covered, and must be on the lowest livable areas of the home. This would be either the basement or the first floor if there is no basement.

In 2008, the Marble Institute of America, which also represents the granite industry, hired Environmental Health & Engineering, Inc., to study radon emissions from granite countertops. According to their report, titled "Assessing Exposure to Radon and Radiation from Granite Countertops November 21, 2008 - Prepared by Environmental Health & Engineering, Inc.", the company tested 213 samples from 112 types of stone. Comparing the results to the US EPA estimated background level of radon radiation outdoors (0.4 pCi/liter (pico-curies / liter)), showed the majority of samples were between non-detectible (0) and 0.1 pCi/L. The US EPA urges action if radon levels in homes are greater than 4.0 pCi/L - or ten times the outdoor background levels. The 4.0 pCi/l limit causes about the same risk for cancer as smoking a half a pack of cigarettes per day. The radiation in the study samples were 40 times less than this limit.

The study did find a select number of “hot” stones. Figure 1 shows three samples; Nile Gold, Juparana Bordeaux, and Kashmir Gold. To address this, the Marble Institute of America is developing testing standards to be implemented at the quarries. These will protect not only homeowners but the workers that cut and shape the stone.

Carbon Footprint

From a LEED certification, or Green Building standpoint, the energy intensity of bringing the stone to the construction site should be considered. Most of the "fancy" stone comes from Brazil, Northern Africa & the Middle East. It is quarried and shipped to Italy or France for finishing, then shipped to the USA for resale. Some companies will ship direct from Brazil to the Eastern seaboard. Given its weight, the fuel use to transport may be considerable, but this author has yet to see a Life Cycle Analysis (LCA) on this. The Marble Institute website says they are working on LCA studies of stones to be released early 2011.

Alternatives to Granite

Installed costs of granite can add up quickly and range widely. Typical mid-quality stones cost $60 / sf, with high-end stone upwards of $100/ sf. There are many alternatives to granite that can be installed for less than, or equal to the lower figure.

PaperStone from KlipTech Composites is a dense, hard, water-resistant, solid-surface composite material made from cellulose fiber (paper) and a non-petroleum phenolic resin derived from cashew shells. The product is available with either 50% or 100% post-consumer recycled paper content and is used for everything from countertops to skateboard ramps. PaperStone also comes in FSC certified source.

Cashew-nut shell liquid (CSNL) has a long history of industrial uses, including in typewriter rolls and brake linings. Both PaperStone and CSNL are Made in the USA, have zero-VOCs, and are Cradle-2-Cradle Silver certified. Average cost is $25 / sf for 3/4" thick material (contractors price ) - not installed.

Marmoleum, natural linoleum flooring, can be used as a countertop material - its made of natural jute backing, pine tree resin and pigments. The color goes all the way through the sheets so scratches don't show. The surface is also aseptic, meaning not a place that fosters bacterial growth - good for kitchens, and health clinics! A backing board would need to be created and the Marmoleum glued to that for a counter-top. Forbo, the maker of Marlmoleum also has a Low-VOC adhesive for the flooring. An installed cost may be $9 -15/square foot with the backer and labor.

BioGlass is a 100% post-consumer recycled glass product that comes in large slabs. It can be backlit for a very sophisticated look. It is not tempered, but has a high tensile strength due to the fusing process used to make the glass pieces stick together. It comes in 1" thick slabs, which do not break easily. Cost per square foot is about $40 for materials. It requires a custom install job like a solid-surface counter top. The material is made in, and imported from Europe.

Ice-Stone is a terrazzo-like substance that has 100% recycled glass content. It's made in Brooklyn, NY, has zero-VOCs and is Cradle-2-Cradle Gold certified. Installed costs are similar to granite ($50 - 60/ sf) due to the cutting and shaping that needs to be done. Ice stone can be fragile while being installed because it does not flex (bend) well. Once mounted and secured it will last a long time.

In addition more traditional countertop materials can be used like ceramic tile, concrete and stainless steel.

Hope this helps!

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