Granite countertops popular in modern kitchens are usually radioactive, and in some cases emit extremely dangerous levels of radiation.

This issue has been widely reported, but the public remains unconcerned because of a popular misconception that there is no risk. Medical and health experts aware of the issue are quick to reassure the public that there is nothing to worry about, yet what they’re really thinking is: “I wouldn’t have them in my house.” The reality is, granite can exhibit hazardous levels of radiation.

Video: I tested my own granite countertop at home and was shocked by the result, the warning alarm went off on the radiation monitor! [Video uploading…]

Every slab of granite is different, because of course it’s naturally-occurring igneous rock. Each slab or granite formed under different conditions, and even within a single slab the composition is not homogeneous. The fact is, some slabs of granite when tested exhibit extremely high radioactive emissions. Most slabs are more radioactive than alternative materials or the background level of radiation in your home.

Granite tends to contain radioisotopes, primarily uranium, thorium and radium. (Yes, you did read that correctly, and yes uranium is the fissile material used as the active ingredient of nuclear weapons, primarily uranium-235, and yes this isotope is found in granite.) Potassium radioisotopes are also present in granite. These radioisotopes emit gamma rays, x-rays, as well as beta particles and alpha particles (listed in descending order of harmfulness). When beta particles strike metal, it tends to release x-rays, especially denser metals like lead (Bremsstrahlung radiation). Countertops have been found emitting 100 times the normal “background level” of radiation. (Background levels vary between locations, and some parts of the UK for example are radiation hotspots precisely because of naturally occurring granite in the local geology.)

The same radionuclides decay into radon gas, a dangerous invisible radioactive gas that is known to cause cancers, especially lung cancer. The US DEEP website acknowledges that a granite countertop can “push radon levels well over the 4 pCi/L guideline from the EPA”. The British government acknowledges that breathing radon from granite is the second biggest cause of lung cancer, killing over 1000 people every year! In extreme cases, when radon is measured, an affected building may have to be evacuated and this is an internationally accepted safety measure.

In short, your granite work top is irradiating your home with invisible rays of ionising radiation, as well as releasing hazardous radioactive gas that can accumulate if not ventilated. This may sound sensationalist, or alarmist, but it is not; it is literally true. Granite can be harmful. Some pieces of granite produce a lot more radiation and release a lot more radon than others. It’s the luck of the draw. Pink granite as a rule-of-thumb is generally the most radioactive type of the rock, but certain slabs of any other type including black granite can exhibit equally dangerous levels of radioactivity. (As I found out to my shock TODAY when I tested the one in my own kitchen by accident while calibrating a Geiger counter for our UFO research projects, instantly alerting me to the severity of the issue and inspiring me to immediately write this article — video above of me detecting high levels of radiation in my own kitchen, apologies for the swearing/expletives!)

Nobody is monitoring this problem. Granite is sourced from geologically diverse areas all over the world without any checks for high radioactivity. Your worktop could come from a uranium mine and you wouldn’t even know it! In the US,  the EPA is aware of the issue, but taking no action. The UK is slightly more proactive, with the HSE very open about the risks and other agencies working to raise awareness and monitor homes, especially in hotspots such as the southwest area of Britain. Nobody checks to see which slabs of granite are the most dangerous. Nobody is measuring radiation readings before or after installation of a new kitchen. Everyone behaves as though this is not a concern — but it is, and people have every right to be aware of the risks. Geiger counters and radiation monitors are cheap, and people should use them. We recommend the GMC-600 digital Geiger counter radiation monitor by GQ Electronics in Seattle, USA. They do also offer much cheaper radiation detectors, although these don’t detect alpha, but that’s fine because radioactive materials in granite also emit all the other kinds anyway. [Ok, so if you’re a science geek, want to become an enthusiast, or just want to impress somebody, get the GMC-600 Plus because that’s twice as sensitive at picking up radioactivity, but honestly all of these are lab grade devices that are more than sensitive enough to assess the radioactivity of a slab of granite accurately in 10 minutes — just watch the average air dose on the screen.] (I’m currently based in the UK, and mine arrived 24 hours after I ordered it, via DHL.) Chip in with your neighbours, get one, and share it. Teach your kids some science along the way. Likewise, radon detectors are readily available commercially.

If you have a granite work surface or are considering getting one, it would be sensible to check its radiation levels — ideally before you purchase. It would be negligent to ignore the danger, and irrational to assume that your piece of granite is safe. Nobody else has your back on this, so it’s all on you.