ML19156A167
| ML19156A167 | |
| Person / Time | |
|---|---|
| Issue date: | 06/05/2019 |
| From: | Donna-Beth Howe NRC/NMSS/DMSST |
| To: | |
| D HOWE MSST | |
| Shared Package | |
| ML19156A166 | List: |
| References | |
| NRC-2019-000187 | |
| Download: ML19156A167 (26) | |
Text
June 5, 2019 MEMORANDUM TO: File FROM: Donna-Beth Howe, Ph.D. /RA/
Medical Safety and Events Assessment Branch Division of Materials Safety, Security, State and Tribal Programs Office of Nuclear Material Safety and Safeguards
SUBJECT:
FOIA NRC-2019-000187 REQUEST FOR DECEMBER 21, 2001 RESPONSE TO TECHNICAL ASSISTANCE REQUEST DATED MAY 18, 2001, RELEASE CRITERIA FOR CATS TREATED WITH RADIOACTIVE IODINE In 2001, a licensee in Region II, Radiocat LLC, submitted an amendment requesting earlier release of its radioactive cats to members of the public (i.e., their owners). The licensee provided analyzed measurement data and calculations to support this request. The region submitted a technical assistance request (TAR) to U.S. Nuclear Regulatory Commission (NRC) for guidance on the licensees proposed release criteria and whether credit could be given for verbal instructions. The attached NRC December 21, 2001, response to the May 18, 2001, TAR request from Region II was based on information supplied by the licensee and was not intended to serve as a precedent for anyone other than the licensee.
Subsequent to the TAR response, NRC was informed by the licensee that there were errors in the data collection, assumptions, calculations and conclusions provided to support the amendment request and the TAR response. The data presented as Attachment 2 to the original TAR response had data collection and analysis errors resulting in flawed conclusions. Further, the data presented in Attachment 5 also had fundamental analysis errors and also could not be used to estimate exposure rates for members of the public.
This memorandum documents that there were errors in the information provided by the licensee and the licensees conclusions based on this information that were referenced in the attached December 21, 2001 TAR response. This information was not used in not used as the basis for NRCs position to release radioactive cats into the public.
CONTACT: Donna-Beth Howe, NMSS/MSST 301-415-5441
File 2 The company then provided new information and measurement data from 100 cats. The NRC reviewed the new information and on February 24, 2003 revised the TAR response.
Attachment:
Memo: J. Hickey, December 21, 2001
File 2 File
SUBJECT:
FOIA NRC-2019-000187 REQUEST FOR DECEMBER 21, 2001 RESPONSE TO TECHNICAL ASSISTANCE REQUEST DATED MAY 18, 2001, RELEASE CRITERIA FOR CATS TREATED WITH RADIOACTIVE IODINE DATE June 5, 2019 ADAMS ML19156A167 Office MSST MSST Name DBHowe CEinberg Date 6/5/19 6/5/19 OFFICIAL RECORD COPY
File 2 File 2 D. Collins 2 Because neither the reviewer nor the licensee should expect the owner's strict compliance with the instructions, the licensee should include a sufficient safety margin in the instructions to account for this uncertainty.
The license reviewer may accept a proposed veterinary cat release criteria based upon a minimum number of days after 1-131 treatment (not less than 4 complete days after treatment) and maximum dose rate (normally 0.25 milliRoentgen/hour (mR/hr) at 1 foot). This does not relieve the licensee from providing written instructions and assurance that each release will be in compliance with 10 CFR 20.1301. If the instructions pertaining to the extent and duration of contact permitted with the cat are easy for the owner to comply with, and it appears that the potential dose would be well below 100 mrem, it may be acceptable, on a case-by-case basis, to release a cat with a radiation dose measurement as high as 0.5 mR/hr at 1 foot. Regardless of the release level used, the licensee should have records to document that the veterinary patient release criterion used for an individual patient will result in compliance with 10 CFR 20.1301.
Since the 1-131 effective half-life, radiation profile, typical behavior pattern, and living situation for each cat are different, the actual release date needs to be established for each individual cat.
This determination should be based upon the radiation measurement and effective half-life of 1-131 for the patient at the time of release. As a minimum, two consecutive daily radiation measurements made at the same time of day and same distance from the cat are needed to calculate the effective half-life of 1-131 for the treated cat. When cats are released, the licensee should assume that over time there will probably be diminishing compliance by the owner with the licensee's instructions. Additional consideration may be necessary when establishing the release date for an 1-131 treated cat to a home with small children.
BACKGROUND:
NRC originally authorized release of cats treated with 1-131 when: the dose rate was less than 1 mR/hr at 6 inches (0.25 mR/hr at 1 foot); instructions were provided to the owners; and the licensee could demonstrate that the limits of 10 CFR 20.1301 would not be exceeded (see , Health Physics Position 286). This guidance continues to be a good bench mark that can be used to estimate when the patient may be released. Its use, however, must also be combined with patient specific information and radiation data. The 0.25 mR/hr at 1 foot is a conservative release criteria. If the owner follows the instructions to limit interaction with the cat for the first few days, it is unlikely that a person would receive a 100 mrem dose even considering diminishing compliance with the instructions after the first few days.
File 2 Applying the 0.25 mR/hr at 1 ft criterion to measurements provided by one licensee, shows that only a few cats could be released 4 days after treatment (Attachment 2, day 5 of the table) and some cats would have to be held beyond 8 days. Holding these cats longer than the 4 to 8 days may not be necessary to assure compliance with 10 CFR 20.1301. Higher release levels may be appropriate for specific situations, but each higher release level will require a greater degree of compliance by the owner with the licensee's instructions over longer periods of time.
File 2 File 2 File 2 2
Ml_ -ATLANTIC RADIATION PHYSICS, I.
File 7233- D HANOVER PARKWAY - 2 (301) 345-6803 GREENBELT, MID 20770 EFFECTIVE I-LkLF-LIFE FOR SODIUM IODIDE IODL\7E-131 INJECTED IN FELIXFS, DETERMINED BY OBSERVED EXPOSURERATE FROM 04 /12/99 THROUGH 05 /03/99 Rob--t S. Kubchi,B.Sý. "
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File 2 File 2 REVIEWER NOTES Distance Perspectives The measurement distances used by several licensees include radiation measurements at 1 meter, 1 foot, and 6 inches. NRC's definition of the" whole body" in 10 CFR Part 20 is the head, trunk (including male The distances gonads), arms above elbow, or legs above knee. provided are put into perspective by relating them to distances from the highest activity that NRC defines as the "whole measured from the cat to the center of the area of the person body. "
One One meter is the approximately distance from a cat lying on the floor to a standing adult. foot is distance from a cat approximately an arm's distance. Thus, one foot could either be the to a person patting a cat when keeping the cat at arm's distance or the distance from a cat lying on the floor to an adult sitting in a chair near the cat. Although six inches would be the maximum inches is a better distance from a cat to an adult holding the cat in their lap, three estimate of this distance from a cat. All these distances should at least be halved when considering small children.
an adult driver and a cat During transportation, one foot is approximately the distance between in a carrier if the in the front passenger seat of a car. This distance would be between 1-2 feet cat were in the back seat, and may approach 1 meter if the cat was in the back of a van or station wagon.
Radiocat - 1999 Radiation measurement and effective half-life Data Veterinarians typically use 3- to 5-millicuries to treat feline hyperthyroidism. Radiocat, provided data collected on 36 cats treated between April 12- 26, 1999, at the licensee's Maryland facility (Attachment 2).
The data consisted of observed exposure rate measurements made 1 foot from the thyroid-region for each cat after injection and subsequently approximately 1, 3, 4, 5, and 6 days after treatment. In most cases, measurements were stopped after a reading of 0.4 mR/hr or less after day 4. This data was used to calculate 1-131 effective half-lives for each cat. For 29 of the cats, the 1-131 effective half-lives at day 1 ranged from a low of 1.0 to a high of 4.5 days; for the remaining 7 cats there was no decline in radiation measurements.
-life for these The licensee incorrectly concluded the 1-131 effective half animals was zero. This error lowered the licensee's average 1-131 effective half life to 1.7 days when it should have been 2.1 days for those animals with declining measurements. Although the animals with no decline in measurements should have been assigned 1-131 effective half lives of 8 days (the physical half life of 1-131), the measurement data at 3 days after injections shows a marked reduction in radiation levels to those similar to the other cats.
The 1-131 effective half-life data presented for 3, 4, 5, 6,and 7 days after 1-131 administration show variation between different days for the same cat. In some cases, the 1-131 effective half lives increased with time. There was also variation among cats. As evidenced by the large standard deviations resulting from simple averaging, the data sample is probably too small to draw statistical conclusions. At their time
File 2 estimated I of release, most cats (26 of 36) had an 131 effective half-life of 1.5 days or less. The longest 1-131 effective half-life was 3.1 days.
Attachment 4
File 2 File 2 File 2 File 2 Radiation Safety Program (Continued) 10.10 Area Radiation Survey Procedures: Area survey procedures will N to be NRC established Regulatory and Guide 10.8 implemented according to the procedures found in Appendix 5 mR/hr and 0.2 Trigger (Revision 2, August 1987)and . unrestricted levels areas, for respectively. exposure rate Trigger surveys levels shall be for removable mR/hr for restricted dpm per 100 crnm as per Table N-1 in Appendix N to NRC contamination shall be 200 2, August 1987). An operational check to verify proper Regulatory Guide 10.8 (Revision source shall be conducted each portable survey instrument of the portable response survey with of a instrumentation. dedicated the dose area check following An exposure rate and removable and day prior to the use be conducted the the cage.
last injection contamination survey shall placement of the animal in Routine surveys shall be performed as follows:
area surveys Exposure rate area surveys shall These be performed routine any day radioactive shall include materials package are received, receipt handled, and/or administered. waste.
compactor, and patient quarantine area. An exposure rate area, dose injection area, in the area used to store radioactive waste during each area survey shall be conducted are used (i.e., survey An will be conducted each week when week radioactive materials administered to patients).
exposure rate area survey shall be radioactive materials for each week are radioactive materials to the area area), are including used, monitor unrestricted areas the conducted, ward (restricted directly below adjacent to the radiation area (see Item 10.13 of this application). Action levels for exposure rate animal quarantine at 5 mR/hr and 2 mR/hr for restricted and unrestricted areas, area surveys shall be set respectively.
personnel
- Personnel contamination surveys administered, shall be and performed anytime any day egress radioactive from materials any restricted are received, handled, and/or this restricted area shall monitor their hands and feet for potential area. Personnel exiting a survey with a pancake
File 2 GM detector. Measurement contamination with meter equipped shall be made in a low background area.
- Routine removable contamination are only surveys administered shall be performed I day each at These week). least weekly following surveys. shall the last administered dose (doses were received and administered, the quarantine area, waste include areas where unit doses compaction area, and waste storage area.
Records of routine surveys shall be maintained in accordance with requirements of 10 CFR, Part 20.
10.11 Release of the Patients treatment Treated of benign with 1-131:hyperthyroidism. a Typical minimum 5 mCi will administered of 5Injected days until activities patients the residual shall of 4 be to confined be is 500to a JlCi given for facility for activity single isolation cage at the are confined at the facility for 5 to 7 days. Exposure rates will be or less.
0.5 mR/hr at 1 foot before Typically patients and must be less than release. Written measured periodically be the time of special care procedures will reviewed, signed, and provided to the owner at patient release.
Item 10 RADIOCAT, L.L.C. July 1999 NRC-New p. 3 of 6 Attachment 5
File 2 File 2 File 2 File 2 File 2 File 2 File 2 2
File 2 will be retained 0.0125 gCi resulting in a TEDE of 21 mrem. Cats order three days to further reduce dose by another must a minimum of dose rate at 1 meter In addition the external of magnitude.
not exceed 0.5 mrem/hour.
will be reviewed and signed by the special care procedures These Written time of admission and at the time of release.
owner at the procedures follow.
Item 10 14 15 , of2000 12 45-2530-01p. July Radio cat 45-2533001