Tag: Radiation treatment for cancer

Why Do We Fear Radiation 7

What Does the Term Low Dose Radiation Really Mean?

Scientists in Radiation Research or those in the Nuclear Power Industry define radiation levels over 100mSv as high dose. Levels must be under 100 mSv to be called low dose. In the medical field the term low dose is not defined and treatment doses are described as high, medium or low. This is very confusing as in the medical literature low dose refers to levels of radiation that are extremely high and usually thousands of mSv.

Dose Makes the Poison

We all know that too much of anything is bad for us, even water. I was a student in Vietnam War days and remember being horrified at the use of water torture. A prisoner was tied down, a funnel put in his mouth and water poured in his mouth until he told all or…

Conversely, it seems likely that too little of almost anything can also be harmful. There is a sweet spot for everything but this zone varies from person to person, species to species and depends on the mineral, the vitamin, the substance or activity, and even radiation. Even arsenic is needed as a co-factor for one enzyme to work.

Ah, What About Dose Rate?

De Toledo et al. 2006

Yes, the graph above is real! There was far more chromosome damage in the control cells than in the cells receiving 10cGy (100mSv) spread out over 48 hours. We now know about many of the changes that occur in cells and tissues and organs dosed with radiation.

We may know more about low dose radiation and its effect on the body than almost any other substance. Thousands and thousands of scientific papers have been published. A book published by Dr Antone L Brooks summarised the work of a US DOE research group he led as Chief Scientist in the period 1998 to 2008 with over 800 references. I have read this book which I obtained a couple of years ago plus hundreds of other scientific and medical journal articles and I read more each day.

There is a major difference between the effects of high and low dose radiation. At low doses and low dose rates the system has time to repair damage that occurs. Most of the biochemical changes are very positive and can even protect the cell or tissue from further insult.

Very High Background Radiation Areas Of Ramsar, Iran – An Example of Adaptive Response

“An in vitro (in the lab) challenge dose of 1.5 Gy (1,500mSv) of gamma rays was administered to the lymphocytes, which showed significantly reduced frequency for chromosome aberrations of people living in the high background compared to those in normal background areas in and near Ramsar.

Specifically, inhabitants of high background radiation areas had about 50% the average of induced chromosomal abnormalities of normal background radiation areas inhabitants following this exposure.” Health Physics 82(1):p 87-93, Jan 2002.

All Living Things on Earth Can Repair Low-Dose Rate Ionizing Radiation

Most of the repair mechanisms seem to have evolved very early in the history of life on Earth at a time when radiation levels were very high. Without these repair mechanisms, life could not have evolved to use oxygen in energy production and there would not be any plants or animals on land. More on how this works in a future blog. All living things have these repair mechanisms.

I have a hypothesis that the reason we can’t sense radiation is that we don’t need to do so. There would have been no evolutionary advantage in having that ability.