Legislative and administrative controls are in place to ensure there is no overuse of nitrates or other fertilisers by farmers on food crops. The code of good agricultural practice, which was agreed with the Department of the Environment and Local Government, covers the timing and application of fertilisers and the precautions necessary to prevent pollution of water, etc. Farmers participating in the regional operational programmes are being obliged to conform with the code. In addition, manufacturers and retailers of fertilisers are under regular supervision by the Department's inspectors to ensure full compliance with their legal obligations and requirements in this area.