Estimation of external irradiation of children due to the use of coal-slag as building material in Tatabánya, Hungary

Slags, derived from coal mined in the neighborhood of the town of Tatabánya in Hungary, have elevated concentrations of 226Ra (850–2400 Bq kg−1). These slags and ashes have been used as filling and insulating material for building houses, blocks of flats, schools and kindergartens and to fill playgrounds and roads. Therefore, the concentrations of radionuclides in the slag samples were determined and compared to the regulations of some European countries on radiological aspects of building materials. According to these regulations, most of the slags would not be allowed to be used without restrictions. We considered the measured dose rates and the time children spend in the kindergartens, schools, dwellings and playgrounds containing these slags. The external gamma dose gives 33 mSv to age 18 while the world average is 9.6 mSv considering the same occupancy. This means an extra 1.3 mSv average annual dose.