Physics 2000 Einstein's Legacy X-Rays

X-Ray and DNA

The real hazard is if the x-rays affect the DNA of cells.

D N A . . . that's like the brain of a cell.

That's the one, good ol' DeoxyriboNucleic Acid. The DNA tells the cell how to reproduce, or make a copy, of itself. If the DNA is damaged, this damage can be passed on to new cells. For the levels of radiation you get at the dentist and the doctor, the body is able to repair most all of the damage done.

If that's the case, why don't those dentists and doctors stay in the room with you? They must know something that I don't know.

Having x-rays taken a couple times a year isn't a big deal. But why should dentists and doctors be exposed to x-rays day in and day out as a part of their job? There is no need for them to take that risk.

All of this stuff with x-rays has something to do with cancer, right?

That's right. Cancer is a group of cells with damaged DNA that are out of control and making too many copies of themselves. Keep in mind that there are many steps to go from DNA damage to cancer.

After all you've said, is it really safe to have x-rays taken at dentists and doctors offices? I don't want to get cancer.

Low doses of x-rays cause a negligible increase in the risk of cancer. Don't forget, there are many things that can cause cancer, from various chemicals to radon gas and cigarettes. X-rays are a mixed blessing. If no x-rays are absorbed by the body, the image would come out white - that's not useful to a doctor. So some x-rays have to be absorbed. That's why dentists and doctors give low doses of x-rays to you, enough to see what is going on inside of you while minimizing any risk to you.

Darn, I was hoping for a scientific excuse for avoiding the dentist.

Not this time.

> 22857th