X Ray radiations might be sequentionally accumulating in the walls of x ray tubes with each production of x rays
X-ray does not really accumulate or cause any significant alteration in x-ray transmission. Primary mechanism of x-ray tube ageing is usually caused by outgazing and cathode degradation.
That information is not true.
X-rays do not "accumulate" in the material of the X-ray tube.
The term "absorption" is used to describe decrease of intensity of X-ray beam when passing through any material object (including air and the walls of X-ray tube) as a result of a wide spectrum of interactions of the X-rays with matter. However X-rays do not activate the matter (in tot became radioactive thereafter). All the processes induced by passing X-rays (Rayleigh and Compton scattering, fluorescence, Auger electron emission) are immediately finished after the X-ray beam is off.
Also I do not thing the electron beam in X-ray tube can activate the anode material. This process happens at energy of electrons at least few orders of magnitude higher.
Has anyone tried to quantify the absorbed or adsorbed radiation in wall of X Ray tubes
Second issue is how to differentiate absorbed vs absorbed radiation in wall of tubes .
Third is lead coating is used for absorption of soft X rays whether this is also a concern
1. The X-ray physics including absorption (look for attenuation) you'll find in:
https://www-pub.iaea.org/MTCD/Publications/PDF/Pub1564webNew-74666420.pdf
2. Adsorption of X-rays does not exist, so you don't need to worry about at all. All you can observe is absorption.
3. Lead - yes this metal is toxic and makes negative changes to your body if gets inside. But as long as it stays in the equipment it is safe. Thus:
- do not touch the lead elements; if you did - wash immediately your hands, especially before you eat something,
- do not manipulate lead shields /alter anything in the instrument unless you are really specialist in this (from the questions I see that's not the case),
- after you finish to use your equipment give it back for recycling, do not just throw out its elements - in this case toxic lead will be spread around and will became dangerous to you and other people.
All answers are right.
Just an addition to Nikolay's answer;
degradation of the anode/target surface *) is another point with respect to tube ageing, especially for high power x-ray tubes.
*) via roughness and even cracks