Impact des gisements des phosphates sur la radioactivité dans les échantillons d’eau naturelle et d’air au Marocag

Impact of the phosphate layers on the radioactivity in the natural water samples and air in Morocco In this work, we present the results of radioactivity measurements in some samples of phosphate deposits and in samples in interaction with these  phosphate deposits such air and water. In phosphate samples, we have determined with gamma spectrometry using a well NaI(Tl) detector, concentrations of uranium in some samples of unrefined Moroccan phosphates. In air, we have measured, with nuclear solid track detector LR 115 type II,the volumic activity of 222 Rn in some dwellings situated in phosphate areas. In water, we have measured activities of uranium and radium radio-isotopes ( 234 U, 238 U) with alpha spectrometry and those of radium ( 226 Ra, 228 Ra) with gamma spectrometry using a 220 cm 3 low-background well type gamma ray detector in the aboratoire Souterrain de Modane (LSM-Centre National de la Recherche Scientifique (CNRS/CEA, France). The obtained results in Moroccan  phosphate samples and in samples in interaction with them are comparable to those habitually obtained in the same samples in the world and these activity do not present any risk for public health. Some harmful effects in the longterm could be avoided by simple precautions such ventilation of dwellings and localities of mining treatment.