The highest cumulative radiation dose received by the teenagers employed at the crippled Fukushima No. 1 power plant is 56.89 millisieverts, Tokyo Electric Power Co. said Thursday.
About 20,000 nuclear workers have been exposed to radiation since the Fukushima crisis began in March 2011.
Of them, 64 were 18 to 19 years old and the oldest was 84, according to data up to February submitted to the World Health Organization. There were also 26 workers aged 70 and over.
On average, doses were highest for those in their 20s, at 15.86 millisieverts, followed by 11.64 millisieverts for those in their 40s, who comprised the largest age group, with 5,893 people.
The average dose for teenagers was 8.26 millisieverts, with the one who got the highest dose an actual Tepco employee rather than a subcontractor.
The oldest Tepco worker was 73.
Tepco added up both external and internal radiation exposure to compile the data.