Event Notification Report for June 06, 2025

MEDICAL EVENT

The following summary of information was provided by the licensee via phone and email:

On June 6, 2025, a technologist injected Tc-99m Pertechnetate into the nebulizer instead of Tc-99m DTPA (diethylene-triamine-pentaacetate) for a lung perfusion ventilation study. The patient was an 11-year-old child with a weight of 61 lbs. (27.72 kg). The nuclear medicine technologist grabbed the wrong syringe and did not verify the information on the label before injecting into the nebulizer. The technologist has been advised by the physician on the need to ensure the labeling is correct prior to injection or use and to verify that it contains the correct compound for the correct study. The patient's family and the referring physician have been notified.

Initial indications of patient dose was 63.9 rem whole body (due to Tc-99m pertechnetate) with an initially prescribed activity of 18 mCi (Tc-99m DTPA) to the lungs. No indication of acute blood changes or radiation sickness. The licensee does not intend to call REAC/TS.

* * * RETRACTION ON 06/10/25 AT 1435 EDT FROM DAVID RHOE TO KERBY SCALES * * *

The following information was provided by the licensee via phone and email:

"The original dosimetry estimate has been revised and indicates no organ dose exceeds the 50 rem limit or the 5 rem effective dose. The dose that was reported as 63.9 Rem was meant to be for an organ dose and not whole body. After much assistance from the NRC staff, a revised dosimetry estimate has been performed.

"The estimate was performed using the MIRDcalc program with the dose of 18 mCi Tc-99m for a 10-year-old female."


Notified R1DO (Warnek), NMSS (Allen), and NMSS Events Notification via email.

A Medical Event may indicate potential problems in a medical facility's use of radioactive materials. It does not necessarily result in harm to the patient.

AGREEMENT STATE REPORT - MEDICAL EVENT

The following report was received by the Pennsylvania Bureau of Radiation Protection, Department of Environmental Protection (the Department) via email:

"On June 6, 2025, the licensee informed the Department of a medical event. It is reportable as per 10 CFR 35.3045. On that day, the licensee was performing a Lu-177 dotatate procedure when it was noticed about halfway into the procedure that the pump infusion setup had a slow, obscured, and contained leak onto underlying absorbent paper. The procedure was then stopped. The prescribed dose was 200mCi and it is estimated at this time that approximately 70-90 mCi were administered. Both the referring physician and the patient were notified the same day. No overexposures were recorded. No harm is expected to the patient.

"The Department will perform a reactive inspection. More information will be provided as received."

PA NMED Event Number: PA250010

* * * UPDATE ON 6/12/2025 AT 0934 EDT FROM JOHN CHIPPO TO ERNEST WEST * * *

The following report was received by the Pennsylvania Bureau of Radiation Protection via email:

"On June 6, 2025, the licensee was performing the second (of four) Lu-177 dotatate (Lutathera) treatments. The patient was prescribed 200 mCi of Lu-177 dotatate. A slow, obscured leak in the side port of the 3-way stopcock was discovered approximately halfway through the 30-minute administration despite the side-port being properly capped. The remaining dosage (11.4 ml of 25 ml) was slowly pushed by hand after an adjustment was made to the stopcock to stop the leak and the infusion was completed. Subsequent radiological measurements by radiation safety of the absorbent containing the leaked material and of the patient were immediately presumptive for a significant loss of material, which was confirmed by additional measurements and calculations. A medical event was declared upon finding the patient received less than 80 percent of the intended dose. It is estimated that approximately 88.4 mCi were administered. All leaked material was contained to the underlying, leakproof absorbent and the articles situated upon it; no other areas of contamination were found. Both the referring physician and the patient were notified the same day. No overexposures were recorded. No harm is expected to the patient."

Notified R1DO (Warnek), and NMSS Events Notification (email)

A Medical Event may indicate potential problems in a medical facility's use of radioactive materials. It does not necessarily result in harm to the patient.

PART 21 - THERMAL OVERLOAD OF VOLTAGE REGULATORS

The following information was provided by the licensee via phone and email:

"This is an initial report notification pursuant to 10 CFR Part 21.21.

"Cook Nuclear Plant completed an internal evaluation concerning an issue with an emergency diesel generator (EDG) voltage regulator (VR) supplied by Paragon Energy Solutions, LLC. An issue was identified during a surveillance test conducted on April 22, 2025, concerning a thermal overload (TOL) for the VR which spuriously trips causing a condition where the EDG VR can no longer control the generator voltage, resulting in the inability of the EDG to supply automatic onsite emergency AC power. A failure analysis was completed on June 6, 2025, determined that the cause of the spurious trips is associated with a heater dimensional tolerance deficiency lowering the activation threshold of the TOL bimetallic strip and a workmanship deficiency associated with a braided control wire restricting the movement of the TOL pressure bar. Extent of condition examinations were performed and one additional TOL was found to be impacted. The two impacted TOLs have been replaced. A written notification will be provided within 30 days."

Affected Plants: Cook Nuclear Power Plant.

The NRC Resident has been notified.