Page One

Report is correct: fire at labs poses real danger  

Dear Editor, 

Berkeley Lab spokesman Kolb accuses the City of Berkeley science consultant, Institute for Energy and Environmental Research, of using false assumptions ( Lab poses health risk..., 2/7/01) in determining the radiation dose persons might get (18,000 milli- rem) if they were near a National Tritium Labeling Facility (NTLF) building fire.  

Perhaps Kolb doesn't realize these assumptions were recently distributed by the Lawrence Berkeley National Laboratory in a SENES Risk Assessment written by the Lab's own consultant, Owen Hoffman. 

The Lab claims a radioactive fire at the NTLF would be no problem because the heat would cause the tritium plume to rise to a height of 38 meters. The Lawrence Hall of Science (LHS) patio is 40 meters above the NTLF roof. Thus, the radioactive plume would disperse at nose level if the wind were blowing toward the LHS. 

U.S. EPA claims that the cancer risk from an 18,000 millirem exposure would be 7 in 1000. However cancer is only one of the risks from tritium. It also causes infertility, birth defects, genetic damage, mutations and immune suppression. If there were several hundred children visiting the LHS at the time of such a release, the cancer risk for just them would be at least two children.  

For comparison, a death rate, from defective Firestone tires, of less than .0006 per 1000 people caused the recall of thousands if not millions of those tires. At the Lawrence Hall Science 7 cancer cases per 1000, plus countless other maladies, should be sufficient to effect action. Do we have to have cancer deaths, and, if so, how many before we close the National Tritium Labeling Facility? 

Gene Bernardi 

Co-Chair Committee to Minimize Toxic Waste 

Berkeley 

Radiation doses to lab workers too small to measure by blood tests 

Editor: 

The following is a reply to a letter published in the Berkeley Daily Planet on Jan. 31, 2001 ("Labs should test staff blood", signed by Marion Fulk) 

We thank Mr. Fulk for his suggestions, but the methods he proposes do not have the sensitivity to detect the low levels of radiation exposure associated with Berkeley Lab operations.  

Radiation operations at Berkeley Lab are under strict control, and Lab monitoring programs show that personal radiation exposures are only a small fraction of the federal limits of 5,000 millirem (mrem) per year for workers; 100 mrem per year for members of the public; and 10 mrem per year due to offsite emissions of radionuclides like tritium.  

U.S. Department of Energy and Environmental Protection Agency have reviewed the Lab’s monitoring program and agree with this conclusion. The City of Berkeley's environmental consultant, IFEU, also concurred that offsite radiation exposures due to tritium did not exceed the 10 mrem per year limit. 

The blood tests suggested by Mr. Fulk have been used successfully elsewhere to measure effects in individuals exposed to much higher levels of radiation, including survivors of the atomic bombings in Japan and the reactor accident at Chernobyl. In those cases, individual radiation exposures exceeded 5,000 mrem by as much as 10 - to - 20 times or more.  

Monitoring radiation exposures at levels below 5,000 mrem per year can be done by direct measurement of the radiations, not of the effects, which are too small to measure.  

Direct radiation measurements have the sensitivity to provide assurance that worker and public radiation exposures remain below the applicable federal limits mentioned above.  

Background radiation in the San Francisco Bay area exposes all of us at a rate of approximately 260 mrem per year.  

Radiation operations at Berkeley Lab involve an additional exposure to the nearby community of no more than 0.3 mrem per year - 0.1% of the background radiation.  

It is not clear that any method existing today can detect effects in humans due to this small increase in radiation exposure. It is clear that the methods proposed by Mr. Fulk do not have the sensitivity necessary for this purpose. 

Gary H. Zeman, Sc.D. 

Eleanor A. Blakely, Ph.D. 

Lawrence Berkeley National Laboratory