ML20148R316
| ML20148R316 | |
| Person / Time | |
|---|---|
| Issue date: | 07/28/1987 |
| From: | Stello V NRC OFFICE OF THE EXECUTIVE DIRECTOR FOR OPERATIONS (EDO) |
| To: | |
| Shared Package | |
| ML20148R249 | List: |
| References | |
| FOIA-88-125 SECY-87-186, NUDOCS 8804140243 | |
| Download: ML20148R316 (8) | |
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July 28, 1987 SECY-87-186 For:
The Commissioners From:
Victor Stello, Jr.
Executive Director for Operations
Subject:
DISTRIBUTION OF RADI0 ACTIVE GEMS IRRADIATED IN REACTORS TO UNLICENSED PERSONS
Purpose:
To inform t'T Commission of staff plans to halt the distribution of radioactive gems from domestic and foreign reactors to unlicensed persons in the United States.
Background:
Certain minerals, notably topaz, assume an attractive color when irradiated by neutrons in a reactor. The minerals can then be used as semi-precious gems in jewelry such as rings and necklaces.
Neutron irradiation causes the gems to become slightly radioactive.
The primary radionuclides in irradiated topaz gems are tantalum-182 (half-life 115 days), scandium-46 (half-life 84 days), and manganese-54 (half-life 303 days). Varying amounts of other radionuclides may be present, depending on the natural mineral content of the gems. Therefore, low levels of radioactivity remain in irradiated gems for months to years following irradiation.
NRC regulations do not prohibit neutron irradiation of products as such. However, the regulations prohibit both import and domestic distribution of consumer products containing radio-activity except in accordance with a distribution license issued by NRC [see 10 CFR Section 30.14(d)].
If a distribution license is issued, the radioactivity in the consumer products must not exceed the exempt concentrations specified in 10 CFR Section 30.70.
In addition, the regulations prohibit distribution of products designed for application to a human being. Long-standing Agency policy on consumer products specifies that authorization of radio-activity in toy (s, novelties, and adornments (such as jewelry) is inappropriate see 30 FR 3462, March 16, 1965). Therefo hasneverlicensedthedistributionofradioactivegems.{e,NRC i
1.
Note also that in 1983 the Commission prohibited the manufacture and import of l
cloisonne jewelry and similar products containing uranium (48 FR 33697, July 25,
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1983; 49 FR 35611, September 11,1984).
CONTACT:
John Hick,, NMSS 42-74205 8804140243 080408 PDR FOIA ASHDAUGOB-125 PDR
The Commissioners 2
This NRC policy is consistent with the international Nuclear Energy Agency's 1985 policy document, "A Guide for Controlling Consumer Products Containing Radioactive Substances," which states, "There are some products in which the presence of radioactive material would appear to be of no benefit to the users of those products, and therefore should be considered unacceptable in principle.... Examples of such consumer products which are already considered unacceptable in some countries...are articles for personal adornment....The distribution to the public of radioactive sources not incorporated in the construction of complete consumer products is also unacceptable in principle, because in this case the subsequent use and the associated risks could not normally be anticipated, and the benefit could not be predicted in advance.
A further reason is that hazards are in general reduced when radioactive sources are incorporated in complete devices."
Several years ago, the staff took enforcement action to halt import of radioactive topaz gems from a reactor in Brazil. Until 1986, the staff viewed that case as an isolated incident. However, in 1986, the staff received numerous inquiries which indicated that
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large amounts of neutron-irradiated topaz, from both domestic and foreign reactors, were being distributed in the U.S.
The staff has also noticed blue topaz jewelry featured in many retail catalogs, in April and May 1986, the staff received two license applications specifically requesting authorization to distribute radioactive gems. Several other U.S. research reactor licensees have informally indicated interest in irradiating gems if approved by HRC.
Discussion:
The staff has verified that at least one domestic research reactor licensee (University of Missouri) is distributing large amounts of irradiated topaz to unlicensed persons.
(Domestic power reactors are not involved.) The reports of imported topaz are more difficult to verify; however, the staff has concluded because of the large number of reports received from knowledgeable persons that substantial quantities of radioactive topaz are also being imported.
Sales of the domestic and imported gems apparently amount to millions of dollars per year. The irradiated topaz cannot be easily identified by appearance, because there are several types and colors of topaz on the market.
Potential radiation exposure and the associated public health hazard cannot be precisely evaluated because data are difficult to obtain on an unregulated activity. The staff's preliminary radiological assessment of the gems is included in Enclosure 1, and we will j
continue our evaluation as more gems become available. Based on the current limited data, the staff believes that there is not a significant health hazard associated with the radioactive gems. Therefore, the staff does not believe that it is necessary to recall gems already distributed, or to perform mass screening of consumers' gems for radioactivity. However, the current unauthorized distribution of radioactive gems is a violation of NRC regulations, and the gems represent a source of unnecessary, low-level radiation exposure to the public, i
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The Commissioners 3
The Office of Nuclear Reactor Regulation issued a Generic Letter to all non-power reactor licensees on June 25, 1986, discussing NRC requirements for distribution of irradiated consumer products.
Region III has inspected the University of Missouri reactor, and thelicenseeagreedtocertainrestricgionsonthereleaseof irradiated gems to unlicensed persons.
The staff has not yet taken any formal enforcement action against any licensee or taken final action on the two pending license applications. The staff wanted to review the situation thoroughly prior to taking final action, for the following reasons:
(1) The public health hazard is believed to be low.
(2) The economic impact on domestic research reactors could be significant. The University of Missouri uses income derived from its gem irradiation program to fund other reactor research, development, and education programs.
(3) The involvement of foreign reactors, possibly with the approval of their governments, complicates the issue.
Given the large number of unlicensed wholesalers importing jewelry, it is difficult to identify and inspect potential violators.
During 1986-1987 the staff discussed the issue with research reactor licensees, national and international gem trade associa-tions, and representatives of the international Nuclear Energy Agency. After thorough review, the staff has concluded that NRC should act to halt distribution of reactor-irradiated gems, based on the following considerations:
(1) The unauthorized distribution of irradiated gems containing residual radioactivity is a violation of NRC regulations
[10CFRSection30.14(d)].
(2) The staff does not believe that it is appropriate to license distribution of the gems because this would conflict with well-established policy against use of radioactive adorn-ments such as jewelry. The gems represent a source of unjustified, low-level radiation exposure to the public.
The staff has no basis to recomend a change in policy, and, in any case, a change in policy would involve complex issues which would take a long time to resolve.
2.
The licensee proposed to Region III an improved screening method which the licensee maintained was adequate to demonstrate that released gems did not contain radioactivity significantly different from background. Region III did not pursue enforcement action pending review by NRC Headquarters.
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The Commissioners 4
(3) The NRC has never established "de minimis" levels below which the radioactivity in consumer products such as gems might be disregarded.
Development of "de minimis" levels wouldinvolvecomglexissueswhichcannotberesolvedina short time frame.
(4) Various licensees and others have requested that NRC promptl) take a definitive position on irradiated gems in the interest of regulatory consistency and fairness as well as protection of the public health and safety.
In two weeks, the staff plans to proceed with the following actions to halt domestic consnerce in irradiated gems:
(1) Denial of two pending license applications (Enclosures 2 and3).
(2) Notification of all non-power reactor licensees of our position against distribution of irradiated gems (Enclosure 4 Draft Generic Letter).
(3) Appropriate enforcement action to halt irradiation and distribution of gems by domestic reactor licensees.
(4) Requesting se U.S. Customs Service to halt import of topaz unless it is certified as not irradiated, and offering NRC staff cooperation in addressing the problem.
(b)
Issuing a public announcement (Enclosure 5).
The staff also plans to pursue the issue of irradiated gems in the international arena, because the ultimate solution must rely on a consistent policy among nations where reactors are operating.
Note that the above actions may result in requests for hearings.
3.
The establishment of "de minimis" levels would, in effect, be a reconsideration of 10 CFR Sections 30.14(d) and 30.70. Such reconsideration would entail an evaluation of the potential range of public exposures and health risks from unrestricted distribution and use of gems and any other materials subject to the same "de minimis" standards, the benefits of such distribution and use, and the measuring techniques or standards by which "de minimis" levels would be demonstrated. The staff notes that it is not evident at this time that practical measurement techniques can demonstrate that large numbers of irradiated gems fall below the current limits specified in 10 CFR Section 30.70.
The Commissioners 5
This paper has been coordinated with the Office of the General Counsel, and there is no legal objection.
The staff anticipates media interest and public concern over this issue because it involves a consumer product. The various staff offices will coordinate with appropriate outside agencies and be prepared to respond to public inquiries.
ctor Stello, Executive Director for Operations
Enclosures:
1.
Staff's Radiological Assessment 2.
Draft Denial of GA Technologies Inc., Application 3.
Draf t Denial of Nuclear Theory and Technologies, Inc., Application 4.
Draft Generic Letter to Non-Power Reactor Licensees 5.
Draft Public Announcement DISTRIBUTION:
Congnissioners OGC (H Street)
HMSS STAFF PRELIMINARY RADIOLOGICAL ASSESSMENT FOR GEMSTONES CONTAINING RADI0 ACTIVE MATERIAL CONTACT: Donald Cool or John Hickey, FTS 427-4205
Background
Certain minerals, notably topaz, assume an attractive color when irradiated by neutrons in a reactor.
The minerals can then be used as semi-precious gems in jewelry such as rings and necklaces.
Neutron irradiation causes the gems to become slightly radioactive. The primary radionuclides in irradiated topaz gems are tantalum-182 (half-life 115 days), scandium-46 (half-life 84 days), and manganese-54 (half-life 303 days). Varying amounts of other radionuclides may be present, depending on the natural mineral content of the gems. Therefore, low levels of radioactivity remain in irradiated gems for months to years following irradiation.
Neutron-irradiated topaz gems are not easily identified by appearance, because other topaz gems of various colors are also on the market.
Some of the gems contain natural color, and some have been treated by gama rays, which do not cause radioactivity in the stones. Jewelry experts have reported to NRC that most neutron-irradiated topaz can be identified by its "London-blue" color.
Potential Radiation Hazard The staff has analyzed topaz samples from both domestic and foreign reactors.
These samples cannot be considered representative of all irradiated topaz sold to consumers, because of the large volume and numerous suppliers of gems. The staff will analyze additional samples as they become available.
As discussed below, the analysis performed up to now does not indicate a potential hazard large enough to warrant remedial action such as recalling gems or screening them for radioactivity.
Although preliminary data indicates that the potential radiation hazard I
I appears to be low, the staff is proceeding to halt further imports and domestic distribution of neutron-irradiated gems, because:
(1) unauthorized import or domestic distribution of the gems is a violation of NRC regulations, (2) the gems represent a source of unnecessary, low-level radiation exposure to consumers, (3) long-standing agency policy prohibits introduction of even
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low levels of radioactivity into consumer adornments such as gems, and (4) prior to considering authorization of distribution of radioactive gems, the agency would have to complete a thorough evaluation of the potential hazard from the low-level radiation exposures to both consumers and processors of the gems, balanced against the marginal benefit associated with their use in jewelry.
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Assessment of Gems Already Possessed by Customers Information available to the staff indicates that gems usually contain less that 2 nanocuries of radioactivity per gram. At this level, a portable survey instrument such as a micro-R meter or Geiger-Mueller counter might not indicate radioactivity above normal background. One licensee has reported to NRC that topaz gems at 2 nanocuries per gram read up to 3.5 microroentgens per hour above background with a micro-R meter.
Recent measurements by NRC inspectors using a micro-R meter were negligible unless several gems were gathered together. These measurements would indicate that gems continuously worn could deliver a dose to a small area of the body up to 30 millirems per year. Measurements with thermo-I luminscent dosimeters indicated dose rates up to about 100 millirems per year above background.
There is considerable uncertainty associated with these measurements, because of the low radiation levels involved. Natural background radiation is about 100 millirems per year.
In 1981, Region I inspectors used a thennoluminescent dosimeter to measure the dose rate from a large topaz (5 grams) containing about 3 nanocuries radio-activity per gram. The surface dose rate was 0.27 millirad per hour.
For a stone containing 2 nanocuries per gram, the dose rate for contact with a gemstone is a sumed to be approximately 0.2 mrem per hour. The staff has chosen this as a "worst case." Under the maximum exposure conditions, a stone might be in contact with the skin of an individual for 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> per day, 365 days per year.
The total exposure under this condition, allowing for decay with a half-life of 115 days, would be about 700 mrem per year to the local skin area.
For the "worst case," the exposure to the whole body would be much less than that calculated above.
Exposure rate from a point source decreases approximately as the square of the distance. Therefore, the dose rate at 2 centimeters would be 1/4 the exposure at 1 cm, or approximately 0.05 mrem /hr. At 4 centimeters, the value would be 1/16 of the value at 1 cn, or approximately 0.013 mrem /hr.
The total dose received during a year would be reduced in a similar manner (175 mrem at 2 centimeters and 45 mrem at 4 cm).
Based on these assumptions, the effective whole body dose equivalent and the dose to any single organ would l
appear to be well within International Comission on Radiological Protection recomendations for exposure of members of the public (100 mrem per year and 5 rem per year respectively).
The risk esgimates in the scientific literature for fatal skin cancer are about 1x10" per A skin dose of 700 mrem from a gemstone corresponds to ariskof0.7x10"gad. This should be considered an upper limit, because the risk estimates in the literature are based on skin cancer resulting from larger radiation doses to larger areas of skin.
In any case, if one million people were exposed to 700 mrem each from gemstones, we would expect less than one case of fatal skin cancer. The doses would not be expected to cause short-tenn clinical effects, such as skin lesions.
The NRC staff has considered the potential dose and risk in other scenarios involving the handling or limited wearing of neutron irradiated gemstones.
The staff has concluded that the potential risk to consumers under these
3 circumstances is much lower than that described above.
The NRC staff does not believe that the irradiated gemstones already available to the general public constitute a hazard significant enough to require remedial action. Therefore, the staff does not recommend that individuals who may possess these gemstones need to discard them or have them screened for radioactivity.
Individuals who wish to limit their exposure could do so by limiting their time wearing the gemstones for a year so that the radioactivity could decay to much lower levels. Storage or disposal of the gemstones should result in essentially no radiation exposure.
Consumers who do not wish the gems at all might wish to check whether they can be returned to their place of purchase.
Although the staff does not recommend that individuals try to screen their gemstones for radioactivity, there may be those individuals who still wish to do so. The staff believes that preliminary screening can be accomplished with a micro-R type meter in close contact with the stone in question. Any reading above background could indicate the presence of induced activity up to or even greater than 2 nanocuries per gram. More thorough analysis can be accomplished using a shielded sodium iodide or germanium-lithium detector for measuring radioactivity, and thermoluminescent dosimeter chips (preferably thin lithium borate) for direct radiation.
For purposes of providing advice to persons who do have gemstones screened for radioactivity, a discrimination level of 2 nanocuries per gram (nCi/g) or a surface dose rate of 0.2 millirem per hour (mrem /hr) measured by a thermoluminescent dosimeter is suggested.
For activities below this level, individuals might be advised that normal wearing of the gemstones, i.e. during the day but removed while sleeping, would result in insignificant risk.
If the radioactivity is above 2 nCi/g or 0.2 mrem /hr the individual might be advised to store the gemstones for an appropriate length of time before using them.
If any radiat'on data is obtained for gemstones, the NRC staff would like to be notified, particularly if the gems contain greater than 2 nCi/g or exhibit greater than 0.2 mrem /hr direct radiation.
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