An Employment Training Corporation scheme, called community work scheme, is resulting in precarious work, according to GWU general secretary Tony Zarb.
These workers work 30 hours a week within local councils for which they get paid a flat rate of €25.
The union will be meeting the Government to ensure that this abuse is brought to an end by removing or changing the scheme.
To add insult to injury, he said, if workers refused to work under the scheme they were struck off the unemployment register.
Mr Zarb added that the time had come for a law that specifically tackled precarious employment.