Five sites are on the latest list for failing to meet the necessary environmental standards set out by the Environment Protection Agency (EPA).
One of the companies, food processor Arrow Group, is owned by the Queally brothers, who also own Dawn Meats.
Arrow Group previously appeared on the environment watchlist in January this year.
All the companies on the list face further enforcement action from the EPA to secure compliance.
The five sites represent less than 1% of industrial sites licensed by the EPA, but account for 21% of complaints received.
Three sites are new to the list, while Glanbia Food Ireland Ltd and Rosderra Irish Meats have been removed from the list that was published in January.
The five companies included are:
- Arrow Group, Kildare – noise and odour complaints.
- Euroflex Teoranta, Donegal – emissions to air and waste management.
- Western Brand Group Ltd, Mayo – wastewater management.
- East Cork Landfill Site, Cork – landfill gas and leachate management.
- Arran Chemical Company Ltd, Roscommon – emissions to air and groundwater.
Licensed facilities are identified as national priority sites for enforcement using a system developed by the EPA.
Points are allocated to each site based on compliance data such as complaints, incidents and non-compliances over the previous six months.
Sites which exceed a certain threshold become a national priority site and are targeted by the EPA for further enforcement action.