Strategy for population triage based on dicentric analysis.
After large-scale accidental overexposure to ionizing radiation, a rapid triage of the exposed population can be performed by scoring dicentrics and ring chromosomes among 50 metaphases. This is rapid but is not accurate because the sensitivity is around 0.5 Gy. After the triage step, dose can be estimated by scoring 500 metaphases. This is lengthy but very accurate because the sensitivity is between 0.1 and 0.2 Gy. To improve the methodology, we propose the use of software for automatic dicentric scoring that was tested on victims of an accident in Dakar. Manual scoring of 50 metaphases was carried out, then manual scoring of 500 metaphases, and automatic scoring. Comparison between the dose classifications obtained with manual scoring on 50 metaphases and 500 metaphases showed 50% misclassification with the manual scoring on 50 metaphases. Comparison between the dose classifications obtained with the automatic scoring and manual scoring on 500 metaphases showed only 4.35% misclassification with the automatic scoring. The automatic scoring method is more accurate than the manual scoring on 50 metaphases and can therefore be used for triage, and in place of the manual scoring on 500 metaphases method for individual dose estimation, because it is as accurate and much faster.
Vaurijoux
Aurélie
A
Laboratoire de Dosimétrie Biologique, Institut de Radioprotection et de Sûreté Nucléaire (IRSN), 92262 Fontenay-aux-Roses, France. aurelie.vaurijoux@irsn.fr
Gruel
Gaëtan
G
Pouzoulet
Frédéric
F
Grégoire
Eric
E
Martin
Cécile
C
Roch-Lefèvre
Sandrine
S
Voisin
Pascale
P
Voisin
Philippe
P
Roy
Laurence
L
D002869:Chromosome Aberrations; D004307:Dose-Response Relationship, Radiation; D006801:Humans; D008677:Metaphase; D011829:Radiation Dosage; D018788:Radioactive Hazard Release; D014218:Triage