asked the Minister for the Environment if he will approximate the percentage figure for transboundary air pollution to this country principally for acid rain and its components.

Information of the kind referred to in the question is available only in relation to the deposition of sulphur (dry and wet).

Data from the European Monitoring and Evaluation Programme (EMEP) for the period from October 1980 to May 1981 and from March 1982 to November 1982 in relation to estimated emissions and depositions of sulphur shows that during that period some 28 per cent of the total deposition of sulphur in Ireland resulted from sources in Ireland. A further 30 per cent resulted from emissions in other EC countries; some 3 per cent resulted from emissions in non EC countries; and the source of 39 per cent of depositions was undetermined. These estimates are based on computer models designed to predict transboundary fluxes and depositions of sulphur throughout Europe. The work of updating sulphur emission inventories in the EMEP context is continuing.