Slashing the minimum wage exposes thousands to exploitation by unscrupulous employers while raising nothing for the exchequer, it has been claimed.
As the Dail passed the controversial one euro cut opposition politicians accused the Government of a race to the bottom for the most vulnerable in society.
The Financial Emergency Measures Bill also covers cuts to public sector pensions and reduces the Taoiseach's pay by 14,000 euro and ministers' pay by more than 10,000 euro.
But the Labour Party said the sweetener of Government pay cuts would not leave Brian Cowen or his Cabinet on the breadline.
Joe Costello, Dublin Central TD, said: "The 11.5% cut in the minimum wage is not going to add one cent to the exchequer while it will expose thousands of people to exploitation by unscrupulous employers and to poverty.
"Already nearly 120,000 workers are deemed to be living below the poverty line in Ireland. This assault on the minimum wage could open the floodgates and sharply increase the numbers of working poor."
The Bill reduces the minimum wage from 8.65 euro to 7.65 euro and the change will only apply to new employees and not those on existing contracts.
Michael Noonan, Fine Gael's finance spokesman, said the Bill could leave workers on the wage at risk of losing their job.
"I don't want to cast aspersions on any group of employers but there is a real and genuine fear that people on the existing minimum wage will be let go and they'll be replaced by people on the new minimum wage which is 40 euro a week less."
As the Dail debated the measure protesters demonstrated outside over the Budget, which also cuts child benefit and social welfare, and brings lower earners into the tax base.