On its meeting on 20 June 2003 the Technical and Scientific Committee for the Nuclear Emergency Preparedness (NBE MTT) of the Governmental Co-ordination Committee requested the participants of the National Environmental Radiation Monitoring System (HAKSER) that, in addition to their regular annual summary of the results of environmental monitoring around the Paks Nuclear Power Plant, they prepare a special report on the environmental effects and additional exposure of the population caused by the severe incident that occurred on 10-11 April 2003. The special report under the editorship of Andor Kerekes OKK-OSSKI, National Research Institute for Radiobiology and Radiohygiene) has been completed and published on the web sites of HAEA and OSSKI. ((http://www.osski.hu/sugeu/szammer/paksuzav.htm) (www.oah.hu/kiadvanyok/egyeb kiadványok)) Major findings of the report are the following: · As for the air-born emissions, the severe incident occurring on 10-11 April 2003 caused significant emissions approaching the annual limit values imposed on the whole plant in the case of radio-iodine. · Relying on the results of the environmental monitoring program it can be stated that, except for the immediate neighbourhood (the area of the monitoring stations of type A), effect of the emissions could only be detected in a small fraction of samples /measurements. · 131I concentration values measured within 30 km around the NPP exceeded the detection limit only in a few instances. As for their impact on the environment and the population, these levels are insignificant. · The specialised institution of the public health authority (OKK OSSKI) assessed the dose contribution of air-born and liquid emissions and found 120 nSv for the population on the south part of Paks and 16 nSv for the adult inhabitants of Gerjen. These values supported the conclusion, that the incident did not give significant contribution to the radiation exposure of the population.