There are calls for the Government to introduce incentives to stop people using smoky coal.
It comes as a decision was made to not bring in an outright ban against the fuel that causes high levels of air pollution.
It’s since reported Letterkenny had higher levels of dangerous particles in the air than in New Delhi at a time last week.
Spikes in air pollution have also been recorded in Waterford, Kerry and Clare.
Mayor of Letterkenny, Independent Councillor John O’Donnell, says there’s only so much local authorities can do: