X-rays are a wonderful medical technology that has the potential for great harm, including genetic damage, cancer and atherosclerosis. X-ray damage accumulates and thus there is no safe level.
There is little doubt that x-ray technology (x-rays, CT scans, fluoroscopy) in medicine has done much good and is an invaluable diagnostic tool. Although I seriously question its usefulness as a therapeutic tool (e.g. cancer radiation therapy), that will not be the focus of this article.
X-rays are high-energy nuclear emissions that have the ability to pass right through tissue and leave an image on a film, called a radiograph (the film itself is not an “x-ray”). Less emission gets through denser tissue like bone, and more goes through soft tissue to darken the film. This results in the contrast, the picture of our insides, seen on the films – light areas are dense tissues, darker areas are less dense.
That little lesson in radiology aside, it’s what the x-ray does as it passes through the body that should be of concern to all. The high-energy x-ray particles can wreak havoc on their journey through tissue. When they hit electrons they confer upon them high levels of unnatural energy. Like a bull in a china shop, these electrons can cause mutations including deletions and translocations of DNA material. The wreckage is often beyond the capability of DNA repair mechanisms. The resulting instability of the chromosome is a precursor to cancer. Cancer is, in effect, the inability of a cell to any longer know its place and behave within its normal constraints. The control mechanism for cell behavior is the genetic material with which x-rays and their misbehaving electron progeny play havoc.
This sounds like free-radical activity, but is different in that it is far more energetic and potentially damaging. The body has mechanisms in place to scavenge and quench free radicals, but x-ray energy is several orders in magnitude beyond those neutralizing capabilities.
X-ray mutational damage can kill a cell or alter it. If the cell is altered, that change stays with it since the genetic material will replicate the error. If more damage to the genetic material occurs, the results are additive.
Remember that. Radiation damage is cumulative. It never goes away, it is just added to until the cell dies or the genetic aberration results in cancer and resultant organism death.
There is NO safe level of radiation. It is a risk versus benefit game as is all of medicine.
There are those within the medical community who argue (with substantial supporting data) that the 300 million or so x-rays taken each year add up to a very significant factor in cancer mortality and even atherosclerosis. The latter is a result of mutational damage in the endothelium (coronary blood vessel wall) to create a mini tumor nidus from which an atherosclerotic plaque emerges.
Since x-rays always cause damage, and the damage is related to the number and strength of exposures, the obvious solution is to have fewer x-rays and lower dose x-rays. But don’t get real comfortable with that either. Recent research has shown that repair of low dose radiation damage to genetic material may be ignored or delayed by cellular repair mechanisms. High doses that kill cells, preventing them from unbridled reproduction (cancer), might be better than the low doses. But high doses create low dose scatter and more widespread potential damage.
How’s that for a confusing mess?
The point is that even the experts aren’t sure of the degree of damage. But they all are sure of the damage. We should take the hint.
Unfortunately technicians and radiologists do not always critically control x-ray dosing. They are concerned with diagnostic images that are easy to read, not so much with what the x-rays are doing as they are not so gently perambulating through your tissues. Since adverse effects are not immediate and would be impossible to tie to the techniques used, caution can be pretty much thrown to the wind. People do not always behave in your best interests if there are no consequences to them for their actions. I am not saying this always occurs and that medical personnel are not concerned for your safety, just alerting you to the fact the door is wide open for sloppy work.
It is estimated that dose reduction, beam collimation (control), rare-earth screens and filtration, carbon fiber materials, more extensive lead shielding, decrease in contrast resolution and use of a pulsed system in digital radiography and an array of constraining techniques in fluoroscopy could reduce exposure by several fold.
That’s what they can do. What you can do is not submit to x-rays unless absolutely necessary. Don’t run to the emergency room every time you stub your toe or feel an ache. Don’t do everything physicians say without question. Find dentists who will only take x-rays when it can be proven to you it is absolutely necessary. Offer to sign liability waivers if they want. Tell them you have already had too many x-rays and you know the dangers are cumulative.
The bottom line is that the vast majority of x-rays are unnecessary and physicians know it. Any experienced practitioner can usually tell you what’s wrong (usually nothing that will not cure itself with a little time) before they even see you, and with a little history taking and palpation (touchy-feely) they can get even closer. But they are hesitant (understandably) to give you their experienced wisdom because they are worried about their liability (rightly so), not your chromosomal damage which will not show up for years and would by then be impossible to relate to their x-rays.
So you must take control over your own body. You make the decision about x-rays, and any other medical intervention for that matter, by getting informed.
Weigh the risk versus the benefit. And remember, any medical intervention is a risk.
References:
Committee for Nuclear Responsibility, San Francisco, CA, 1999.
(http://www.ratical.org/radiation/CNR/RMP/execsumm.html)
Gofman JW, “What Are the Main Critiques of the 1999 Study by Gofman, after Three Years of Peer-Review?” Committee for Nuclear Responsibility, San Francisco, CA, 2002.
(http://www.ratical.org/radiation/CNR/RMP/6critiques.html)
Testimony submitted to the FDA, March 31, 2003.
