Northern Ireland's Health Minister said yesterday a full investigation would be conducted into chemical contamination at a DHSS office block in Lisahally on the outskirts of Derry on Monday night. Twenty-seven civil servants suffered minor contamination.
Three men and four women were still being treated in Altnagelvin Hospital yesterday after they had inhaled methol bromide fumes. The chemical is an insecticide which was used to fumigate the offices after the discovery of paper lice.
Among the casualties still detained in hospital are two officers of the civil servants' union, NIPSA, and two others who took up posts in the office block on Monday. None of the detained casualties is in a serious condition.
Dr Colin Hamilton, a public health consultant, said both the casualties and hospital staff had to be decontaminated after the incident.
The Minister, Mr George Howarth, said the contaminated office block, where 250 civil servants work, would remain closed until the problem had been resolved. Mr Howarth, who visited the casualties in hospital yesterday, said he was gravely concerned by what had happened. "There was fumigation carried out at the offices over the weekend and when people arrived for work, they started to feel progressively more ill as the day wore on," he said.