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MIT and NIH Incidents produce NRC Information Notice 95-51
The following is a notice which addresses the tow referenced
incidents, AND, suggestions for regulatory changes. One has to do with
when the NRC is notified - reporting requirements. This issue has been
addressed here in Radsafe previously. Here is the NRC's perspective.
Sandy Perle
Supervisor Health Physics
Florida Power and Light Company
Nuclear Division
(407) 694-4219 Office
(407) 694-3706 Fax
sandy_perle@email.fpl.com
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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.
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.
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
conducting surveys with adequate, calibrated equipment.
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.
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