Information Notice No. 95-51: Recent Incidents Involving Potential Loss of Control of Licensed Material
UNITED STATES
NUCLEAR REGULATORY COMMISSION
OFFICE OF NUCLEAR MATERIAL SAFETY AND SAFEGUARDS
WASHINGTON, D.C. 20555-0001
October 27, 1995
NRC INFORMATION NOTICE 95-51: RECENT INCIDENTS INVOLVING POTENTIAL LOSS OF
CONTROL OF LICENSED MATERIAL
Addressees
All material and fuel cycle licensees.
Purpose
The U.S. Nuclear Regulatory Commission is issuing this information notice to
alert addressees to two recent incidents involving potential loss of control
of licensed material, resulting in internal contamination of individuals. It
is expected that recipients will review the information for applicability to
their facilities and consider actions, as appropriate, to avoid similar
problems. However, suggestions contained in this information notice are not
new NRC requirements; therefore, no specific action nor written response is
required.
Description of Circumstances
Recently, NRC was informed of and responded to two incidents involving
phosphorus-32 (P-32) internal contamination of individuals at biomedical
research facilities. P-32 is widely used in research institutions, as are
many other radionuclides. Although these incidents both involved P-32, the
inherent security issues extend to all facilities using licensed material.
Case 1: On June 30, 1995, a licensee informed NRC that an incident involving
internal contamination of a female researcher had been reported to
the licensee's radiation safety office the previous evening. The
researcher was in her fourth month of pregnancy at the time of the
incident. Contamination was detected when the researcher's husband,
who worked with her at the licensee's facility, performed a routine
survey of their lab. The licensee identified the radionuclide as
P-32. Accidental contamination appeared unlikely because the woman
had stopped working with radioactive material in their lab about a
month before, and because the radioisotope (P-32) identified in
bioassay samples is not of the same type her lab used. Licensee
security officials and the Federal Bureau of Investigation are
investigating the possibility that the woman ingested food or
liquids deliberately contaminated with the radioisotope. Initial
calculations (now being refined by NRC, the licensee, and the
researcher's own technical experts) estimated that the researcher
ingested tens of megabecquerels (hundreds of microcuries) of P-32.
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Subsequent licensee surveys identified a few droplets of P-32 on the
floor in front of a refrigerator in a lounge adjacent to labs the
couple use and an internally contaminated water cooler in the same
building. Urine bioassays of other workers identified approximately
25 additional individuals who have low-level internal P-32
contamination. In early July 1995, NRC sent an Augmented Inspection
Team to investigate the circumstances surrounding the contamination
incident. While the inspection and investigations are ongoing, NRC
has obtained licensee agreement to improve the control of
radioactive materials used in its biological and medical research
programs.
Case 2: On October 16, 1995, a licensee informed NRC that an incident
involving internal contamination of a researcher had occurred at its
facility almost 2 months earlier. Licensee officials told NRC staff
that they had not reported the incident earlier because their
analyses suggest that the researcher's internal dose was below the
10 CFR Part 20 reporting criteria.
According to the licensee, the researcher discovered that he was
contaminated during a routine survey of his work area. Also
according to the licensee, it subsequently detected P-32
contamination on an item of clothing that the researcher had worn
earlier that week, when he had last handled P-32 in the laboratory.
The licensee performed urine bioassays, and informed the researcher
that he may have ingested what was described as a drop of P-32
containing 21.4 megabecquerel (579 microcuries). The researcher has
told licensee campus police that he believes the contamination was
not accidental. NRC and campus police are investigating his
allegation. Also, the researcher has requested that an independent
consultant prepare a second dose estimate.
The licensee initially secured all radioactive materials in the lab
after discovery of the contamination event. Since then, the
licensee has permitted work with radioactive material to resume,
after requiring more stringent inventory and accountability in the
lab and tightening security. On October 17, 1995, NRC dispatched an
Incident Investigation Team to the licensee's site to begin an
immediate investigation of the incident. NRC also sent a letter to
the licensee requiring that certain steps be taken, ensuring among
other things that control of radioisotopes is adequate to provide
reasonable assurance against another such incident. NRC's
investigation is ongoing.
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Discussion
The two recent P-32 internal contamination incidents raise a number of safety
and regulatory issues. NRC is reviewing its regulations to determine if they
need to be revised in light of these events. Among these issues are
radioactive material security and accountability, survey procedures,
preparation for bioassays, and reporting requirements. Each of these issues
is addressed separately below.
a. Security. In controlled or unrestricted areas, licensees are
required by 10 CFR 20.1801 and 20.1802 to secure stored material,
and to control and maintain, under constant surveillance, licensed
material that is not in storage. Access to restricted areas is
required to be controlled to prevent unauthorized access to licensed
material. Licensees should review their programs to ensure that
they have a radiation safety program in place that will prevent
deliberate misuse of radioactive materials in all licensee areas.
b. Accountability. 10 CFR Part 20 requires the reporting of theft or
loss of materials above defined levels. In addition, the Draft
Regulatory Guide DG-0005, "Applications for Licenses of Broad
Scope," published for comment in October 1994, states that license
applicants:
... should develop and maintain a strong inventory and
accountability system. The institution should have the
capability to continually track incoming shipments of
licensed material and account for material usage, decay,
transfer, and disposal. A licensee's inventory and control
system should have the capability to ensure that licensed
possession limits are not exceeded and that material is
accounted for throughout the institution at any given time.
In light of these events, licensees should review their programs to
determine whether they need to improve their radioactive material
accountability systems, commensurate with the scope of their
programs.
c. Detecting licensed material. NRC emphasizes that conducting surveys
with adequate, calibrated equipment is a crucial step in conducting
safe operations. Many commercially available survey instruments,
such as Geiger-Mueller detectors, are capable of detecting P-32,
even after ingestion, in the activity range used in research
facilities. In both of these cases, internal contamination was
originally detected when the researchers conducted routine surveys
of their laboratories and detected high background readings.
Licensees should review their programs to ensure that they are
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d. Bioassay preparation. All licensees are responsible for responding
to incidents. Some licensees already have bioassay programs in
place to comply with the requirement in 10 CFR 20.1502 to monitor
workers whose intake is likely to exceed 10 percent of the
occupational dose limits. Interpretation of bioassay data, when
regulatory thresholds are approached, may be difficult. Important
information on the proper conduct of a bioassay program is provided
in Regulatory Guide 8.9, Rev. 1, July 1993, "Acceptable Concepts,
Models, Equations, and Assumptions for a Bioassay Program" and
NUREG/CR-4884, "Interpretation of Bioassay Measurements." Licensees
that need immediate medical consultation to respond to an ongoing
internal contamination event can contact the Radiation Emergency
Assistance Center/Training Site (REAC/TS), which is funded by the
U.S. Department of Energy to provide consultation in such
situations. The NRC Operations Center can connect callers with
REAC/TS.
If internal contamination is detected, health physics consultants
are commercially available to assist with bioassay and other
response measures. However, licensees that plan to use consultants
may want to identify and make arrangements for those resources now,
rather than wait until an incident occurs. Licensees that need help
in identifying health physics services should contact professional
societies or organizations for references.
e. Food and beverage storage. Generally, licensees have procedures
prohibiting eating, drinking, and smoking in radiologically
restricted areas. In light of these events, licensees should review
their programs to determine how food, particularly lunches, snack
foods, and beverages in unsealed containers, are permitted or stored
in their facilities.
f. Contact NRC if deliberate misuse of licensed material is suspected.
NRC considers deliberate misuse of licensed material to be of
significant regulatory interest, and expects to be contacted in such
situations. Although the magnitude of the dose could be within
NRC's regulatory limits, the possibility that such a dose was
delivered intentionally, and possibly with malice, raises concerns
about a licensee's, a contractor's, or any employee's deliberate
misconduct, as addressed in 10 CFR 30.10, 40.10, 70.10, and 72.12.
In addition, pursuant to 10 CFR 30.9(b), 40.9(b), 70.9(b), and
72.11(b), each licensee is required to "... notify the Commission of
information identified ... as having for the regulated activity a
significant implication for public health and safety ...."
Notification shall be provided in such cases to the Regional
Administrator within 2 working days.
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The issues raised in these two cases should lead licensees to consider
reexamining their own methods to prevent and, if necessary, respond to
internal contamination incidents.
The information in this notice is preliminary, and the investigations and
inspections in these two cases are ongoing. NRC may issue further guidance,
as necessary, once results are known and conclusions drawn on these two cases.
This information notice requires no specific action or written response. If
you have any questions about the information in this notice, please contact
the technical contacts listed below or the appropriate regional office.
/S/'D BY DACOOL
Donald A. Cool, Director
Division of Industrial and
Medical Nuclear Safety
Office of Nuclear Material Safety
and Safeguards
Technical contacts: Scott Moore, NMSS B. J. Holt, RIII
(301) 415-7875 (708) 829-9836
Mohamed Shanbaky, RI Thomas Kozak, RIII
(610) 337-5209 (708) 829-9866
John Potter, RII Linda Howell, RIV
(404) 331-5571 (817) 860-8213
Attachments:
1. List of Emergency Contacts
2. List of Recently Issued NMSS Information Notices
3. List of Recently Issued NRC Information Notices
Attachment 1
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LIST OF EMERGENCY CONTACTS
I. NRC Operations Center
Telephone: 301-816-5100 (will accept collect calls)
II. Radiation Emergency Assistance Center/Training Site (REAC/TS)
Daytime Telephone: 423-576-3131
24-hour Telephone: 423-481-1000 (ask for REAC/TS)
(to consult with a physician)
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