Why is Blood Irradiated?

As described in the Technical Manual (21st Edition) and Circular of Information (December 2021), cellular blood components are irradiated prior to transfusion to prevent the proliferation of viable T lymphocytes which are the immediate cause of Transfusion Associated-Graft Versus Host Disease (TA-GVHD). TA-GVHD, a rare complication (fewer than one per million transfusions result in TA-GVHD), has a fatality rate greater than 90%. Patients at particular risk of TA-GVHD include:

  • Fetal and neonatal recipients of intrauterine transfusions
  • Selected immunocompromised recipients
  • Recipients of cellular components known to be from a blood relative
  • Recipients who have undergone marrow or peripheral blood progenitor cell transplantation
  • Recipients of cellular components whose donor is selected for HLA compatibility

Where Can I Find More Clinical Information?

The Circular of Information for Human Blood and Blood Components has detailed information on indications for use, safety and hazards.

The AABB Technical Manual discusses TA-GVHD, blood irradiation, and radiation safety.

What Type of Blood Irradiation Devices are FDA Cleared?

The following devices are FDA-approved/cleared “for use in the irradiation of blood and blood products (packaged in transfusion bags) to inactivate T-lymphocytes for the prevention of Graft Versus Host Disease...”:

Refer to the FDA website for more information.

US Government Efforts: Risk Reduction and Elimination of Gamma Irradiators

The US NRC requires increased security measures to reduce the risk of unauthorized use of radioactive materials for gamma irradiators.
The US Office of Radiological Security (ORS) offers federally funded security enhancements for radioisotope-based blood irradiators that are above and beyond the NRC’s Part 37 requirements – see Additional Resources section.

The goal of the Cesium Irradiator Replacement Project and the Off-Site Source Recovery Program is to eliminate the use of blood irradiation devices that rely on cesium chloride (Cs-137) in the United States through voluntary replacement. Section 3141 of the John S. McCain National Defense Authorization Act for Fiscal Year 2019 includes a provision that requires the Administrator for Nuclear Security to ensure that goal is met by December 31, 2027.

ORS – Information on X-ray vs. Radioisotopic Irradiator Considerations

ORS - Cesium Irradiator Replacement Project Learn More About Permanent Risk Reduction and Incentives Offered by the Office of Radiological Security

ORS – Frequently Asked Questions

ORS - Viable Alternative Technologies for Permanent Risk Reduction

ORS - Cesium Irradiator Replacement Program (video)

NTI - Preventing a Dirty Bomb: Resources for Hospitals and Research Centers

NTI - NTI Partners with the State of California on Radiological “Dirty Bomb” Risk Reduction

NTI - Nuclear Threat Initiative Partners with New York City on First-of-its-Kind, Citywide Approach to Remove Radiological “Dirty Bomb” Risks

Recent Actions

The Radiological Devices Panel of the Medical Device Advisory Committee met to advise FDA on the device classification of blood irradiators. In its public statement, AABB recommended that no measures be added for use of blood irradiators and that the devices be classified as class I or II. After discussions, the panel advised FDA that class II with general and special controls would be appropriate.