What's New?
.	December Journal
.	December Newsletter
.	Online Registration for HPS 2010 Midyear Meeting Now Available
.	NRC Academic Program Nuclear Education Grants, FY2010, Now Accepting Applications
.	EPA's STAR Graduate and GRO Undergraduate Fellowship Funding Now Accepting Applications

Upcoming Events
.	2010 HPS Midyear Topical Meeting Radiation Risk Communication to the Public 24-27 January 2010 Albuquerque, NM
.	2010 HPS Professional Development School Radiation Risk Communication: Issues and Solutions 27-29 January 2010 Albuquerque, NM

20 November 2009

Biological half-life

The time required for a biological system, such as that of a human, to eliminate, by natural processes, half of the amount of a substance (such as a radioactive material) that has entered it.