background exposure造句怎么写

By scientific measures, the average American gets 620 millirems of radiation each year, half from background exposure, and that number needs to reach 100,000 to be worrisome.

Zhou Libo current wife background exposure, shocked people!

Due to the omnipresence of dioxins, all people have background exposure and a certain level of dioxins in the body, leading to the so-called body burden.