Air pollution in Dublin was at its worst point in the past week in over 30 years.
Data from the Environmental Protection Agency found high levels of pollution last week in Dublin, Clare, Kerry, Cork and Wexford.
The Irish Times reports data from the EPA shows samples taken in Rathmines and Ringsend were 15 times higher than the EU and WHO guidelines.
Levels in Ennis in Co Clare were as high, while guideline limits were also breached in Tralee, Co Kerry, Cork city and Macroom and Enniscorthy, Co Wexford.
The agency says this type of pollution is associated with the burning of solid fuels.
It says air pollution causes the death of 1,300 people every year in the Republic of Ireland.