It's being claimed Irish Water has questions to answer, after unsafe levels of chlorine were found in the supply for about a thousand households in Meath.
A number of children got sick and suffered skin rashes as a result.
Irish Water Customers around the Kilcloon area between Maynooth and Dunboyne are being warned not to drink, wash or use their water for cooking.
The warning affects customers in Kilcloon, Moygaddy, Killeany, Kilgraigue, Harristown, Brownstown, Ballynare, Butlerstown, Staffordstown, Brownrath, Blackhall Little, Waynestown, Harlockstown, Ballymacoll in Co Meath.
Meath East TD Thomas Byrne says the utility was very slow to respond to complaints from customers:
The utility says it is currently flushing out the network in order to make the supply safe again.
Bottled water is being made available to customers in the area at Kilcloon Church.
Customers are being told to run taps and flush toilets to get rid of the chlorinated water in homes.
