radon-222


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radon-222

a radioactive decay product of radium-226 that has been used to fill permanent implants in tumors. It is being replaced by the more manageable radionuclide iodine-125.
References in periodicals archive ?
Concentrations of radon-222 were dichotomized as "<300 pCi/L" and "[greater than or equal to]300 pCi/L," the latter being the limit proposed by the Environmental Protection Agency for public water supplies.
Analyses were repeated for the radon-222 dichotomies of <300 pCi/L" and [greater than or equal to]300 pCi/L (Table 2).
Furthermore, elevated concentrations of radium-226 and radon-222 were reported in some municipal utility districts in this part of Harris County as far back as 20 years.
Radon-222 gas is the first progeny of decaying radium.
Radon-222 is too short-lived to be significantly transferred across the placenta to the fetus.
Radon-222 is not an immediate threat because it stops emitting alpha radiation and decays into lead-214 in 3.
1 Bq/L for (228) Ra; 1 Bq/L for (223-226) Ra) (234) U, and (235) U; 10 Bq/L for (238) U; 100Bq/L for radon-222 ((222) Rn), and 15 [micro]g/L for total uranium (WHO 2004).
Radon-222 con-centration in groundwater and cancer mortality in North Carolina.
The Public Health Service recommends that homeowners monitor for radon-222 and take corrective action where levels of this natural, radioactive pollutant prove high (SN: 9/24/88, p.
Radon-220 is a fifth-generation daughter of thrium-232, and radon-222 is a sixth-generation descendant of uranium-238.
Radon-222 undergoes further decay in several steps to produce four radioactive, chemically reactive "daughter" isotopes with short half-lives (less than 30 minutes) which can attach to walls, floors, or airborne particles that can be inhaled.
The radon-222 they emit has a half-life of nearly four days, more than 5,000 times longer than that of radon-220.