Up to 1, 000 people protested in Limerick city today against plans by the Irish Cement plant in Mungret to change the fuel it uses as part of its production process.
The company want to change from burning fossil fuels to industrial fuels in its giant kiln.
Local people are protesting over the decision by Limerick City and County council to grant permission to the plant to burn fuels such as used tyres and solvents.
The company insisted the practice is safe, that there will be no change in emissions from the plant and that the practice of using industrial fuels is common in cement factories across Europe.
They also said Limerick is the last plant in Ireland to still use fossil fuels, and the change is necessary if it wants to stay competitive and protect the 84 jobs there.
However, people living in the growing suburb of Mungret believe the change in fuel use could result in toxic emissions and affect people's health.
Mungret is a large residential suburb where three new schools are being built to cope with a predicted rise in its population.
Limerick Against Pollution spokesperson Clare Keating, who organised today's march, said they are angry that Limerick Council awarded the planning permission so early without proper consultation or taking into account the concerns of almost 1,500 local householders who objected.
Ms Keating said they remain fundamentally opposed to the plan and their opposition will continue.
She said the granting of permission by the local council to Irish Cement was a setback but they will appeal that decision, and will fight any plans by the Environmental Protection Agency to grant the company a permit to carry out the planned change.