The operator of the crippled Fukushima Daiichi nuclear power plant says it found in the facility’s No.2 reactor radioactive substances that could have resulted from continuous nuclear fission.
The Tokyo Electric Power Company, or TEPCO, said on Wednesday that it detected xenon-133 and xenon-135 in gas taken from the reactor’s containment vessel on the previous day. The substances were reportedly in concentrations of 6 to more than 10 parts per million becquerels per cubic centimeter.
Xenon-135 was also detected in gas samples collected on Wednesday.
Radioactive xenon is produced during nuclear fission.
The half-life of xenon-133 is 5 days, and that of xenon-135 is 9 hours.
TEPCO workers poured a boric acid solution into the reactor on Wednesday to suppress nuclear fission.