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Medical Tests Indicate Internal Contamination Due to June 9 Plutonium Incident

BOULDER, Colo. – New results from sensitive medical tests indicate internal plutonium exposure in a small number of personnel at the National Institute of Standards and Technology (NIST) due to a plutonium spill in a laboratory room June 9.

To protect the privacy of the individuals involved, certain specifics about these tests cannot be made available at this time.

"We are concerned for the health and safety of our personnel and deeply regret these results showing internal plutonium exposure," NIST Deputy Director James M. Turner said. "We are getting advice from the best medical experts in the country and will do everything we can to ensure that the people affected get the best possible medical treatment."

Treatment for plutonium exposure consists of receiving one or more injections of a chelating agent that circulates through the bloodstream and attaches to plutonium atoms in the body to allow them to be excreted more easily in the urine. The principal effect of internal plutonium exposure is a potential increased long-term risk of cancer. Removing as much plutonium as possible from the body reduces the risk, according to plutonium health effects experts.

The contamination was detected in urine samples using a technique called alpha spectroscopy. The test detects weak radiation signals from alpha particles, the principal form of plutonium radiation that can cause health effects.

In consultation with medical experts, NIST has been monitoring the health of the laboratory personnel who potentially could have been exposed as a result of the June 9 incident.

Additional urinalysis testing using thermal ionization mass spectrometry is also being conducted for all personnel potentially exposed. Full results from these tests, which typically detect lower levels of contamination than the alpha spectroscopy tests, are not expected for up to four weeks.

Testing for possible plutonium exposure is complex, and results can be difficult to interpret. NIST is providing updates as results become available and can be summarized appropriately.

Also on Thursday, June 26, three small spots of trace-level contamination, barely above background levels that occur throughout the environment, were discovered in a different NIST building from the location where the spill occurred. The trace contamination was found on items belonging to an individual who was in the lab after the spill occurred on June 9, but before it was reported.

NIST radiation health experts know of no safety or health concerns from the trace levels of surface contamination found yesterday. Health concerns from plutonium occur primarily with inhalation or ingestion.

Turner said, "We are re-interviewing all potentially exposed personnel to determine if any other areas need to be checked to ensure there is no trace contamination remaining."

"We are committed to strengthening our safety program and its implementation to help prevent safety incidents in the future," Turner said.

Additional information on the NIST Boulder plutonium incident is available online.

Released June 27, 2008, Updated February 2, 2023