I suspect you have already been to Florida Department of Health's website, but if not, I recommend it to anyone wishing to get more background about this problem. Since there are not standards for granite slab testing, and a granite yard is a rather intensified situation, it is difficult to get the answer to the first part of your question.
The second part of your question asks about alternatives and that is much easier to answer. Yes! Choose an alternative! Not only for your health, but also because quarrying granite is unhealthy for the workers and the environment. Imagine if you are worried about one slab, what the workers are going through! The particulates from quarrying carry to neighborhoods and the health risks and complaints have been documented and are being studied.
Granite is currently produced in 17 US states. It is also imported from a number of other countries. In order to extract the stone, the earth, vegetation and all natural elements must, of course, be removed from the deposit location with heavy equipment. In other words, granite is an entirely destructive process to the environment.
The man made quartz stone alternatives to granite counters are hard like granite and resist scratching much more than Corian, and even more than some granites. They often have a beautiful natural look, especially in a large field. The quartz is combined with resins and pigment, then heated and compacted into an impermeable surface. One of the nice things about it is that if you have ordered a certain color, you actually get that color, whereas granite can vary hugely, even if it is from the same batch.
Some of the more available brands are: Caesarstone, Cambria, Silestone, Zodiaq and HanStone. Because it is factory made, your slab is much less likely than granite to have fissures or scratches when it arrives. You will need a granite installer to install it. GREENGUARD Environmental Institute has officially certified some brands as low emitting products safe for for indoor applications and ideal where food is being served. Some even have recycled aggregate. Most of the companies will respond to direct requests for environmental information or already have it on their website.
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