Lab results on a ‘suspect package' found at An Post’s Cardiff Lane sorting office have returned negative.
Postal deliveries in the Dublin 2 postal area were suspended because of the incident and will not resume until tomorrow.
Employees at the sorting office were evacuated early this morning when a package 'leaking white powder’ alerted staff to a possible anthrax scare.
The area where the letter was opened was temporarily sealed by Gardaí and the Army to prevent any further possible contamination.
Three workers who may have come into contact with the package were given decontamination showers and were given 'precautionary medical treatment.'
The sorting office off Pearse Street in Dublin is the largest and busiest sorting office in the State, according to An Post.
The vast majority of the 260,000 items of mail waiting to be delivered are business-related and are due to be sorted and delivered tomorrow morning.