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A 0.5 milliCurie Po-210 static eliminator source was lost by 3M Corporation. 3M was performing an inventory and determined the source to be missing on 11/13/2006. The state will follow up with additional details when supplied by the licensee.

• * * UPDATE PROVIDED VIA FAX BY CRAIG VERKE TO JEFF ROTTON AT 1341 EST ON 12/12/06 * * *

The State provided the following information via facsimile:

The lost device is a model P2042 Nucleospot nuclear static eliminator, manufactured by NRD Inc.  The original activity of the source was five millicuries of Polonium-210 at the time of its manufacture in September of 2005. The current, decayed activity of the source is 0.5 millicuries. The static eliminators are leased by NRD for a one year period and returned to NRD at the expiration of the lease.

3M uses about 40 of these devices in weighing balances in research laboratories at 3M Center, St. Paul MN. Receipt, shipment and annual change outs of the devices at the end of their lease is handled by a member of Corporate Health Physics (CHP). An individual in the laboratory where the device is used is designated as the Radiation Safety Officer (RSO) and is responsible for day-to-day use of the device. The RSOs conducts semiannual physical inventories of their devices, most recently in July 2006. The device in question was in use in a laboratory of the 3M Pharmaceutical Division in Building 260 on 3M Center. It was not in the balance where it was normally used when CHP attempted to replace it at the end of the lease in November 2006. It was then learned that the RSO for the laboratory had taken a different position at 3M and had not been in the laboratory since the physical inventory in July.

CHP was not notified of the job transfer by the laboratory RSO. Therefore, there was a period of several months when there was no individual specifically responsible for the device. During that time we believe the device was moved to a different 3M laboratory for use there and placed in a drawer or other storage location by an employee who has since left the company. Since 3M announced plans for the sale of the Pharmaceutical Division, many research employees in that division have taken positions with other companies. The device may have been disposed of in the trash, though this seems unlikely as it has a radioactive material label. It also appears likely that it was stolen as it has no intrinsic value and little usefulness outside of a laboratory.
Radiation exposure would not result from this device in an unrestricted area. The emitted alpha radiation is completely shielded by clothing or the dead skin layer on the outside of the body. The radioactive material is sealed in a capsule, which is further enclosed in the body of the device itself, thus preventing inhalation or ingestion. Wipe tests performed by 3M in January and July, 2006 showed no contamination at a minimum detection level of 1 x 10-6 microcuries.
Actions taken to recover the lost device involved interviews with personnel in the laboratory where it was used and searches of that and surrounding laboratories. Emails were sent to persons working in the laboratories asking them to provide any information they had on the location of the device. Flyers with pictures of the device requesting its return were posted in the laboratories.
Measures to ensure against a recurrence are:

- Reminders to laboratory RSOs and their management to notify Clip of any change in location of a nuclear static eliminator or in the job status of the RSO. - Reminders were given to those working in the laboratories, during the course of the searches, of the need to leave the nuclear static eliminators in their assigned location. Notified NMSS EO (Morell), R3DO (Lara), and ILTAB (via email). THIS MATERIAL EVENT CONTAINS A "LESS THAN CAT 3" LEVEL OF RADIOACTIVE MATERIAL Sources that are "Less than IAEA Category 3 sources," are either sources that are very unlikely to cause permanent injury to individuals or contain a very small amount of radioactive material that would not cause any permanent injury. Some of these sources, such as moisture density gauges or thickness gauges that are Category 4, the amount of unshielded radioactive material, if not safely managed or securely protected, could possibly - although it is unlikely - temporarily injure someone who handled it or were otherwise in contact with it, or who were close to it for a period of many weeks.