A total of 683 complaints were received about smells compared to 300 in 2019. April, the first full month of lockdown, saw the highest number of complaints overall, with 187 lodged.
The EPA is responsible for licencing and monitoring activities at 830 factories and industrial installations across the country and it said 86pc of them attracted no complaints at all.
But it added it was seriously concerned about a number of plants on its ‘national priority sites’ list for the second year in a row.
The Arrow Group attracted 198 complaints about its operations in Naas, Co Kildare where its site includes Dawn Farm Foods, the Culinary Food Group, QK Coldstores and Maudlins Waste Management. Odours and noise were the main issues reported.