[ RadSafe ] Tritium a carcinogen?

[Dukelow, James S Jr]

Steven Dapra wrote:
-----Original Message-----
From: radsafe-bounces at radlab.nl [mailto:radsafe-bounces at radlab.nl] On
Behalf Of Steven Dapra
Sent: Saturday, April 15, 2006 7:39 AM
To: radsafe at radlab.nl
Subject: [ RadSafe ] Tritium a carcinogen?

Apr. 15

         In the recent group of news items posted by Sandy Perle there
was an article about low levels of tritium being detected in the
drinking water near a nuclear power plant.  The german portion of the
article read, "Tritium, a potential carcinogen, is a radioactive form of
hydrogen commonly found in groundwater but more concentrated in water
used in nuclear reactors."

         Are there any verified cases of tritium causing cancer?  If
not, are there any instances in which tritium is plausibly believed to
have caused cancer?

Steven Dapra
sjd at swcp.com

====================

J. Newell Stannard in Ch. 10 of his three-volume Radioactivity and
Health, Battelle Press, 1988, describes the history of research into the
biological effects of tritium.  In Section 10.IV.C.2.b, he details the
fatalities of two Swiss radioluminizers (working in  watch factories
using tritium to luminize the watch dials).  They handled from several
hundred to several thousand curies of tritium activity for three and six
years, using both tritiated gas and water. Quoting Stannard: "The deaths
were due to damage to the hematopoietic system with symptoms referable
to the lung damage.  For reasons that are not clear, changes in white
cells were much less marked than the decrease in the numbers of red
cells, as well as hemoglobin, (hyperchromic anemia).  The authors
classify the disorder as aplastic panmyelocytopenia."

With a maximum beta energy of around 12 kev and a biological half-life
roughly equal to water -- around 10 days, tritium is about as close as a
radionuclide can come to not being a radionuclide, for health effects
purposes, at least.  The exception applies to the case of the two Swiss
workers.  A small fraction of inhaled/ingested/absorbed tritium will
become incorporated in more stable (i.e., longer biological
half-life)biological hydrocarbons.  In a situation of chronic exposure
to high levels of tritium, a significant fraction of the body's
biomolecules may become tritiated.

Best regards.

Jim Dukelow
Pacific Northwest National Laboratory
Richland, WA
Jim.dukelow at pnl.gov

These comments are mine and have not been reviewed and/or approved by my
management or by the U.S. Department of Energy.