NATURAL RADIUM ISOTOPES PRESENT IN SOME COSMETIC PRODUCTS: DETERMINATION OF ACTIVITY CONCENTRATION AND DOSE ESTIMATION.

Since the early days, clays, plant extracts and raw materials have been used for therapeutic and beauty purposes. Nowadays, this use is widely spread, as a huge amount of companies have developed new cosmetics based on natural sources. This may lead to an accumulation of radionuclides that can be hazardous for people. Especially dangerous are radium isotopes (Ra-226,Ra-228), which can be part of the raw materials that cosmetics are made from. In this paper, the concentration of radium isotopes of 18 natural cosmetics was determined. Concentrations resulted in the range 7.9 +/- 5.0-37.6 +/- 12.5 Bq kg(-1) for Ra-226; and 2.5 +/- 1.7-35.4 +/- 2.6 Bq kg(-1) for Ra-228. The effective dose in the skin has been estimated, obtaining a mean value of 13.1 +/- 4.9 mu Sv y(-1). This value is far from the reference level of 50 mSv y(-1) for the public members. Therefore, no radiological risk derived from the use of these samples, has been found.