# What is the problem with using a radionuclide with too long a half-life?

## What is the problem with using a radionuclide with too long a half-life?

The biggest danger from radioisotopes with mid-to-long half lives is that they can keep an entire region of earth nastily radioactive for a very long time, e.g. hundreds or thousands or even tens of thousand of years.

Since the chemical bonding between atoms involves the deformation of atomic electron wavefunctions, the radioactive half-life of an atom can depend on how it is bonded to other atoms. Simply by changing the neighboring atoms that are bonded to a radioactive isotope, we can change its half-life.

Are radioactive isotopes with a short or long half-life more harmful?

Isotopes with a long half-life decay very slowly, and so produce fewer radioactive decays per second; their intensity is less. Istopes with shorter half-lives are more intense. In nuclear waste, isotopes with very short half-lives, say a few days or even a few weeks, are not the major concern.

### Which of the given relation of the half-life is incorrect?

Thus, shorter the half life of an element, greater is its radioactivity, i.e., greater the number of atomsd disintegrating per second. The relation between half life and average life is `t_(1//2) = (0.693)/(lambda) = tau xx 0.693` or `tau = 1.44 t_(1//2)` Mark the incorrect relation.

What is half-life affected by?

Half-life is dependent on both clearance and volume of distribution, such that a decrease in clearance, as might be seen with a CYP1A2 or CYP2C19 substrate, or an increase in volume of distribution will prolong the half-life and lead to a longer dosage interval.

Radioactive half-life is the time required for a quantity of a radioisotope to decay by half. If the half-life of an isotope is relatively short, e.g. a few hours, most of the radioactivity will be gone in a few days.

#### What are the dangers of radioactive isotopes?

Radioactive isotopes can sit in the stomach and irradiate for a long time. High doses can cause sterility or mutations. Radiation can burn skin or cause cancer. Radiation can cause leukaemia and other diseases of the blood.

How does half-life affect dosing?

If a single dose is given every half-life, half of the first dose will be cleared from the body before the next dose. So, after the second dose, there will be 1.5 doses in the body. Half of that is eliminated and then the next dose is given, meaning there are now 1.75 doses in the body.

Why is radioactive half life important?

Knowing about half-lives is important because it enables you to determine when a sample of radioactive material is safe to handle. The rule is that a sample is safe when its radioactivity has dropped below detection limits. And that occurs at 10 half-lives.

## Who would use half-life of radioisotopes?

The half-lives of certain types of radioisotopes are very useful to know. They allow us to determine the ages of very old artifacts. Scientists can use the half-life of Carbon-14 to determine the approximate age of organic objects less than 40,000 years old.