Reader Questions; Can You Test Blood & Saliva For Radiation Exposure?

We solicited (and continue to) readers to send in their questions for us to try to answer. There are so many things people still have questions about related to radiation exposure, the Fukushima disaster and similar issues.

Today’s question is from Jane and she asks: “Can I be tested for levels thru bood work or saliva?”

A good question and it appears you can do this, of course with some caveats and limitations.

Blood Tests
As was recently presented by the Center for Radiological Research at Columbia University Medical Center, they have established a process to do blood tests to look for radiation exposure. The tests look at DNA rather than looking for actual radiation levels.

The RABIT system utilizes a fingerstick of blood, like the standard blood test used routinely by diabetics. The samples enter a robotic system that can automatically analyze them for two measures of radiation exposure. The first, which must be completed within 36 hours of exposure, looks for the number of breaks in double strands of DNA. The second test searches blood cells for micronuclei composed of damaged chromosomes. The second test can be performed several months after exposure.”

Professor Brenner goes on to mention how useful such a test could be to help the public understand what has happened to them and alleviate worry. He mentions how an actual test with a quantifiable result is far more useful for the person exposed than someone just telling them “don’t worry”. If you know one way or the other you can at least deal with that and take proactive action if needed.

We also looked at such testing specific to Cesium. A document from the Delaware Dept.of Health & Human services explains that both blood and saliva can be used to test for exposure to Cesium.
One test can show if you were exposed to a large dose of radioactive cesium. Another test can show cesium in the blood, waste matter, saliva and urine

The CDC also has details on testing related to cesium exposure.
Two types of tests are available for radioactive cesium. One is to see if you have been exposed to a large dose of radiation, and the other is to see if cesium is in your body. The first looks for changes in blood cell counts or in your chromosomes that occur at 3 to 5 times the annual occupational dose limit. It cannot tell if the radiation came from cesium. The second type of test involves examining your blood, feces, saliva, urine, and even your entire body. It is to see if cesium is being excreted from or remains inside your body at levels that are higher than normal. Either the doctor’s office collects and sends the samples to a special lab for testing, or you must go to the lab for testing.”

The CDC mentions how some of these tests don’t look for just cesium but look for radiation exposure damage or levels in general indicating some of these tests can look for broader spectrum exposures rather than just one isotope.

Iodine 131
This document by Duke University shows that iodine 131 can be found in saliva, this is in the context of the substance being used for medical purposes.

The CDC again shows that iodine can be tested for in body substances.
Most physicians do not test for iodine in their offices, but can collect samples and send them to special laboratories. They can also feel the thyroid for lumps that may have been caused by disease or past exposure to radioactive iodine, but the results do not tell the cause. Every person’s body contains a small amount of iodine, but normally not radioactive iodine (such as 131I). Iodine can be measured in the blood, urine, and saliva. The amount is normally measured by its mass (in grams). If the iodine is radioactive, it can be measured by its mass or by its radiation emissions. These emissions are used to tell the amount of radioactive iodine (in curies or becquerels) and the radiation dose it gives to your body (in sieverts or rem).”

Since Iodine 131 has a very short half life any test for specific iodine 131 exposure should be done soon after exposure before the evidence is lost.

As detailed in the information specific to cesium and iodine, saliva can be used to test for exposure. There are time limits as both substances are eventually excreted out of the body.

Check back, we have more reader questions to come.

This article would not be possible without the extensive efforts of the SimplyInfo research team
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