Radon Toxicity in Dogs and Cats

I recently treated a feline patient of mine for a partially difficult respiratory condition. After a few weeks of intensive treatment I am happy to say that he is now feeling well. On a recent visit to the clinic his owner queried as to whether radon poisoning could have had played any role in his recent respiratory illness. The humans in her household are suffering from some health problems and in an effort to identify the cause she is having radon levels tested in her home. Not long after she asked me this question I had the unfortunate opportunity to diagnose one of my favorite patients with primary lung cancer. These two cases motivated me to research radon poisoning, with its possible adverse health effects on pets.

Radon is a naturally occurring, colorless, odorless gas produced by “radium (²²⁶Ra), which is a decay product of Uranium (²³⁸U)¹“. Radon gas is emitted from virtually all rocks and soils as radium and Uranium are found naturally worldwide. Radon gas tends to accumulate in confined spaces such as basements of residential homes, or mines¹. When radon gas is inhaled, it interacts with cells of the respiratory tract, damaging the DNA within them. Proliferation of cells with damaged DNA significantly increases the odds that cancer will develop in affected organs¹.

The carcinogenic effects of radon on human lungs are second only to that of cigarette smoke¹. Furthermore “the proportion of all lung cancers linked to radon in people is estimated to lie between 3% and 14%..¹.” With radon’s documented cancer-causing abilities in humans it is very reasonable to wonder as to its potential hazards in animals. The good news is that to date, there are no epidemiological studies clearly linking the carcinogenic properties of radon on dogs or cats. Additionally no other radon induced health problems have been documented in people¹ or pets, although studies are ongoing.

Even with no clear warnings as to the dangers of radon on pets, because of its known human health risks it none the less behooves you to have radon levels checked in your home. Testing requires some patience as radon gas levels may vary dramatically from week to week, or even hour to hour in homes¹. The EPA suggests that long term radon testing, at least 90 days or longer is best.

While researching this article I found an EPA website that provides a link to information on radon testing for all 50 states, Guam, the US Virgin Islands and Porto Rico. After a few clicks I was able to very quickly download PDF documents on companies that offer Radon testing and one for contractors that can be hired to mitigate radon problems in my home state of Oregon. The website on a whole was user friendly and informative.

In summary no adverse health effects have been documented dogs and cats from radon exposure. Radon health risks are however significant enough in people that testing your home is warranted. If radon levels in your home are unacceptably high, please find a qualified contractor who can make appropriate modifications to your home, which will decrease radon exposure for all those that you care for.

1. WHO handbook on indoor radon: a public health perspective / edited by Hajo Zeeb, and Ferid Shannoun, 2009