Answer to Question #12703 Submitted to "Ask the Experts"

Category: Radiation Basics — Alpha Radiation

The following question was answered by an expert in the appropriate field:


I recently received anonymous messages saying that I have been intentionally poisoned with thorium (most likely via ingestion). Since about the summer of 2017 I have experienced significant neuralgia and peripheral neuropathy, first in the right shoulder area, then expanding down to include most of the right shoulder, arm, and hand. A few months ago, I also started feeling the same on the left side (random on/off burning, tingling, sometimes stabbing pains, in changing locations, that are ephemeral, but felt for some portions of every day in varying degrees). Finally, my lower left leg—the general bone areas—has a somewhat different feeling—similar to what bone cancer might feel like (layperson's diagnosis using various medical websites). I would like to ask if there are any measurements or tests that can be done from outside the body that would detect presence of any radiation. Also, which would be the best devices available for rent (or by a professional service) to check for ionizing radiation in the home and automobile? Thank you for any help or suggestions you may have.


Thorium is a naturally occurring weakly radioactive heavy metal that is unbiquitous in our environment. Thus, it is found in trace amounts in soil, rock, air, water, plants, and animals, including our own bodies. It comes from the food we eat, the water we drink, and the air we breathe and is constantly being taken into our bodies as well as being constantly excreted in urine, feces, sweat, and exhaled air because it is poorly absorbed into the body. 

The query you posed is largely in the nature of a medical and possibly legal nature and, hence, outside the purview of the Health Physics Society Ask The Experts feature. The fact that you have received anonymous messages alleging that you have been intentionally poisoned with thorium would seem to be a matter for law enforcement and should be referred to them. The medical symptoms you describe are best evaluated by consultation with a competent physician. There are, in fact, tests and measurements that can be performed outside the body. These include measurement of thorium in urine and feces that, in conjunction with calculations based on biokinetic models, can determine the amount of thorium in your body. Similarly, there are instruments that measure radiation directly or from air samples. Such tests and measurements and body burden evaluations typically require specialized instrumentation and professional expertise and are not generally available. The radiation control section of your state department of public health can advise you in this regard as well as assisting you in other ways with evaluation of your situation. Detailed information on thorium can be obtained from the publication "Toxicological Profile for Thorium" of the Agency for Toxic Substances and Disease Registry in Atlanta.                

Ron Kathren
Professor Emeritus
Washington State University at Tri-Cities

Ask the Experts is posting answers using only SI (the International System of Units) in accordance with international practice. To convert these to traditional units we have prepared a conversion table. You can also view a diagram to help put the radiation information presented in this question and answer in perspective. Explanations of radiation terms can be found here.
Answer posted on 14 November 2018. The information posted on this web page is intended as general reference information only. Specific facts and circumstances may affect the applicability of concepts, materials, and information described herein. The information provided is not a substitute for professional advice and should not be relied upon in the absence of such professional advice. To the best of our knowledge, answers are correct at the time they are posted. Be advised that over time, requirements could change, new data could be made available, and Internet links could change, affecting the correctness of the answers. Answers are the professional opinions of the expert responding to each question; they do not necessarily represent the position of the Health Physics Society.