All except two of the affected NPCIL workers, who had consumed contaminated water with traces of tritium, have been certified as normal and resumed their duties in the non-radiation area of the Kaiga atomic power station in Karnataka, a top official said on Monday.
Only two persons, who have been found having higher doses of tritiated water in their body, are undergoing the process of removing it, Nuclear Power Corporation of India (NPCIL) Chairman and Managing Director S.K. Jain said.
“No one was hospitalised and all of them were given diuretic agents for excess urination and also re-hydration process to restore their body fluids,” he told reporters here.
“Even the two persons who had high tritium in their body, further medical management is being carried out to bring down their potential radiation exposure to less than that prescribed by the Atomic Energy Regulatory Board (AERB) in a short time,” he said.
Forty eight people had a quicker response to treatment, but the remaining two are taking more time. However, all of them are normal and working in the non-radiation area of the plant, Mr. Jain said.
While the International Commission on Radiation Protection (ICRP) prescribes a radiation exposure limit of 50 mSv per year, the AERB’s limit permits only 30 mSv annually as a matter of abundant caution.
Mr. Jain said contamination of the water cooler, which was located outside the radiation area, was a “mischievous act” by some worker and the company has already filed an FIR with the local district authorities.
“In all NPCIL plants, drinking water is kept in the form of a fountain, where there is no storage of water but in this particular case, it was a water cooler with storage facility as demanded by the workers,” he said.
“Even this water cooler was locked and it has been found that the culprit had used the overflow pipe to contaminate the water,” he added.
Mr. Jain said that only a marginal amount of 5 ml (vial) of tritiated heavy water was put in the cooler.
However, the cooler has been isolated to facilitate the ongoing investigation, he added.