Canadian Cytogenetic Emergency Network (CEN) for biological dosimetry following radiological/nuclear accidents

TLDR

The study aimed to evaluate the Canadian Cytogenetic Emergency Network’s capacity to deliver rapid dicentric‑assay based biological dosimetry for triage in large‑scale radiation emergencies, and to establish it as Canada’s first operational network for such response. A May 2004 workshop recruited 22 clinical cytogenetic laboratories across Canada, which prepared slides from in‑vitro gamma‑irradiated blood, analyzed at least 50 metaphases per slide by 41 technicians, and generated dose estimates using a Health Canada dose‑response curve. Out of 104 dose estimates, 96 (92.3 %) fell within the expected triage range, with half of the laboratories scoring 50 metaphases in ≤1 hour, demonstrating acceptable capacity and expertise for emergency dosimetry and expanding international cytogenetic networks.

Abstract

Purpose: To test the ability of the cytogenetic emergency network (CEN) of laboratories, currently under development across Canada, to provide rapid biological dosimetry using the dicentric assay for triage assessment, that could be implemented in the event of a large-scale radiation/nuclear emergency.Materials and methods: A workshop was held in May 2004 in Toronto, Canada, to introduce the concept of CEN and recruit clinical cytogenetic laboratories at hospitals across the country. Slides were prepared for dicentric assay analysis following in vitro irradiation of blood to a range of gamma-ray doses. A minimum of 50 metaphases per slide were analyzed by 41 people at 22 different laboratories to estimate the exposure level.Results: Dose estimates were calculated based on a dose response curve generated at Health Canada. There were a total of 104 dose estimates and 96 (92.3%) of them fell within the expected range using triage scoring criteria. Half of the laboratories analyzed 50 metaphases in ≤ 1 hour and the time to score them was proportional to dose. The capacity and scoring expertise of the various participating laboratories were found to be generally acceptable.Conclusions: The dose estimates generated through triage scoring by this network were acceptable for emergency biological dosimetry. When this network is fully operational, it will be the first of its kind in Canada able to respond to radiological/nuclear emergencies by providing triage quality biological dosimetry for a large number of samples. This network represents an alternate expansion of existing international emergency biological dosimetry cytogenetic networks.