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Abstract: Adequate radioprotection of the environment requires the identification of biomonitors sensitive to the variation of its radionuclide content. Due to the chemical similarities between calcium and strontium, calcified tissues of mammals are considered to be good 90Sr biomonitors. This work considered Cervus elaphus antlers which, being shed annually, can give information about the importance of radiostrontium contamination in an ecosystem in the time period required for the growth of the antler. The samples were collected at various points of W and SW Spain. The mean value of their 90Sr content was (70 ± 43 (S.D.)) Bq/kg d.w., range (16–218) Bq/kg d.w., and the radionuclide was evenly distributed in the different parts of the antler. There was a good correlation between the antlers’ 90Sr content and the 90Sr deposited in the soil. The antlers’ content of 226Ra (from the natural uranium series) and the contents of some stable elements (Ca, Mg, Sr, and K) were also determined. The values for these stable elements were practically constant in the analyzed samples, and the concentrations measured decreased in the following order: Ca » Mg > K > Sr » 90Sr > 226Ra [Copyright &y& Elsevier]

The anthropogenic ( 137 Cs, 90 Sr, 239+240 Pu and 241 Am) and naturally occurring radionuclide ( 40 K, 234,238 U, 228,230,232 Th, 226 Ra and 210 Pb) content in near surface air present seasonal variations related to natural processes, such as soil erosion, resuspension of fine particles of soil and radon exhalation from soil ( 210 Pb). The objective is to analyze seasonal variations of their concentrations and compare with radiological events (Fukushima fallout and wild fire) in a location without any known source of anthropogenic radionuclides. The 210 Pb, 40 K, and 137 Cs presented annual variations, with maximum activity levels in summer. Solar radiation and rainfall were correlated with 210 Pb and 40 K. The 234,238 U, 228,230,232 Th, 226 Ra, 137 Cs and 90 Sr presented positive correlation with monthly mean values of temperature. The ratio 90 Sr/ 137 Cs was within the range of those reported for soils in Spain. Finally, the maximal effective dose rate was estimated to be 37 and 88 μSv/y for infants and adults, respectively, well below 1 mSv/y reference level. The main contributor to effective dose was 210 Pb, about 92%, followed by: 210 Pb ≫  228,230,232 Th >  226 Ra, 234,238 U >  7 Be, 239+240 Pu >  40 K, 90 Sr >  137 Cs >  22 Na., (Copyright © 2016 Elsevier Ltd. All rights reserved.)