An extensive study of internal radiation exposure in Fukushima Prefecture children detected no radioactive cesium among the examinees, according to the results of a study published Friday.

The study, the first of its kind, involved over 2,700 infants and small children mostly from Fukushima who could have been exposed to radiation during and after the Fukushima No. 1 power plant crisis in 2011. The children were examined by three local medical institutions: Hirata Central Hospital, Minamisoma Municipal General Hospital and Tokiwakai Hospital.

Published in the Proceedings of the Japan Academy magazine, the study examined 2,707 children up to 11 years of age from December 2013 to March 2015, using newly developed whole body counters designed especially for scanning small children.