Caution! The site can't guarantee, that text has age permission. The site is not recommended, if you are less than 18 years old.
The site shows example sentences for English words. How the word or phrase could be used in a sentence?
" ... We have always focused on those radionuclides that can affect us, like Cs-137, Sr-90, Tc-99, I-131 and various isotopes of Pu, Am, U and Np, because these can enter the body, and react or sorb in different tissues and organs. They have various biological half-lives, meaning they can enter biological pathways and be retained in the body for various times and can, if occurring in high enough concentrations, cause problems. ... "