Officials on Wednesday said two of the five workers had died from “acute leukaemia”, the Korea Times reported, citing a study by the Korea National Open University.
The affected workers were responsible for maintaining trains on Lines 1 through 8 of the Seoul Metro.
All five had spent years performing core maintenance tasks, including dismantling, cleaning, repairing, welding, grinding and repainting subway trains.
According to the Korea Times, one was diagnosed in 2009 at age 39 and retired three years later. Another was diagnosed in the same year and retired in 2011 at age 51. The remaining three are still employed.
The latest cases follow last year’s discovery of eight other workers diagnosed with the same conditions – including three deaths – bringing the total number of affected employees at Seoul Metro to 13.
