Seven Christchurch Hospital staff have suffered life-long issues, from toxic fume exposure while working

A Health NZ memo sent to staff, and seen by Newstalk ZB, confirms more than 120-staff fell ill - and one was hospitalised - in October last year, after suffering from exposure.

The radiology workers suffered breathing problems, rashes and headaches from a chemical used in paint work.

The paint has been replaced with an alternate product, and work on the Hospital's third tower re-started last week.

The APEX union says an independent investigation confirmed the seven most seriously impacted by the fumes may have to work elsewhere, while construction is completed.