High school experiment on food (E.coli) irradiation.

[Ken Smith <ksmith@cats.ucsc.edu>]

Radsafers-

I 'm forwarding this message from a local high school student that would
like to perform a science fair experiment on food/E. coli irradiation.  

Our University does not have acceptable sources with which to irradiate her
samples.  If there is a facility willing to help her please contact her
directly via e-mail.  

Ken-
-------------------------
My name is Dana Gravem and I am in tenth grade at Santa Catalina High School
in Monterey. I have participated in the California State Science Fair for the
past three years. In eighth grade I recieved first place in microbiology for
the junior division. In ninth grade I recieved the California State Science
Fair Project of the Year for the senior division, first place in microbiology
for the senior division and an award from an enviornmental health
organization. My advisor is Michael Dalbey at the University of California at
Santa Cruz. I am looking for a facility that would agree to irradiate some
samples of bacteria as part of a science fair project.

My idea for my project is as follows:

Hypothesis: Exposure of bacterial populations to ionizing radiation
elevates the frequency of genetic recombination. That is, if a bacterial
population is irradiated at a level that kills a majority (90-95%) of the
cells, the survivirs will have a higher frequency of genetic recombination
than unirradiated control populations.

Procedure: I propose to irradiate liquid bacterial suspensions in 15 mL
glass vials with plastic screw
caps at 0.5 kiloGray, 1 kiloGray, and 2 kiloGray. I would like to irradiate
four vials at each level: one vial of each of two genotypes of E.coli , one
vial with the 2 E.coli genotypes mixed together and one vial of Bacillus
subtilis. The assay for recombinants will involve plating the bacterial
suspensions on agar plates containing antibiotics. It would be ideal if
I could do the plating immediately after irradiation, so if it is possible to
have a small area where I could set up for a short period of time it would
be helpful. I would bring my own supplies. It would be best if I could do
this during my winter break from school which lasts from February 21 to March
1.

Thank you for your help.
Dana Gravem


Ken Smith
Acting Radiation Safety Officer
University of California
Santa Cruz, CA  95064                   
Voice: (408) 459-3911
Fax: (408) 459-3209
e-mail: ksmith@cats.ucsc.edu