"An increasing number of the cases taken to the Rights Commissioner service come from non-Irish workers, and they are largely successful in the vindication of their rights, " said Kieran Mulvey, chief executive of the Labour Relations Commission.

Rights Commissioners hear complaints from individual workers concerning non-payment of the minimum wage, holidays etc.

"In the month of May alone this year, the service handled a record 654 cases or almost 30 per working day, " Mulvey told the Sunday Tribune. He added that he expects more than 7,000 referrals to be made to the LRC by the end of the year, almost double the service's 2005 caseload.

Mulvey admitted that the increase is putting a strain on the country's nine Rights Commissioners but said that an extra six commissioners would be recruited next year to cope with the demand.

Most of the claims from non-Irish workers are from people working in the country for a few years who are by now aware of the basic rights which they are being denied, said Mulvey.

"Most are over-qualified for the type of work they are doing and there is a lot of angst out there about the way they are being treated at work, " he said.

While the disputes in Gama and Irish Ferries . . . which replaced its Irish workforce with cheaper, non-Irish labour . . . had their own unique history, the "increasing frequency of such disputes" was a cause for concern, said Mulvey.

"With our history of emigration, we above all should be conscious of the need to treat migrant workers fairly. But it appears we have forgotten where we came from, " he said.

Mulvey said he was confident, however, that the tough new worker protection laws proposed under the Towards 2016 national pay agreement will, if operated appropriately, address the issue.

"We invite migrant workers here to keep the economy going. We cannot afford to get a reputation worldwide for then turning around and exploiting the same workers, " he warned.

With regard to discrimination claims under the Employment Equality Act, 64 race cases have been referred to the equality tribunal in the first six months of this year, more than twice as many as in the same six-month period last year.

"Race cases now account for 32% of all employment referrals, " said Melanie Pine, director of the equality tribunal. This is despite the fact that race is just one of nine grounds under which discrimination claims can be made.