Determination of natural radioactivity levels and gamma radiation attenuation coefficients in propolis samples and the study of its antioxidant properties

Abstract

Thanks to its rich content, propolis has been used to protect the hive from all kinds of external influences and for disinfection by bees. Furthermore, it is an important marker for monitoring environmental pollution because the main sources of propolis are plant and secretions. So, the present study aimed to research radiation attenuation capability and the natural radioactivity level of propolis samples. For this reason, both natural radioactivity concentrations (226Ra, 232Th and 40K) and attenuation coefficients (Linear and Mass) in the propolis samples collected from 10 different points in Turkey were measured using high purity germanium detector (HPGe). The average natural radioactivity concentrations in samples were found to be 0.56 ± 0.19, 2.65 ± 0.31 and 70.08 ± 2.42 Bq/kg for 226Ra, 232Th and 40K, respectively. These values were much lower than the average world values (35 Bq/kg for 226Ra, 30 Bq/kg for 232Th and 400 Bq/kg for 40K) reported by United Nations Scientific Committee on Effects of Atomic Radiation (UNSCEAR) in foodstuff. The average linear attenuation coefficient, mass attenuation coefficients and half value layer values for gamma rays with 59.54 keV energy were determined as 0.1970 cm−1, 0.1831 cm2 g−1 and 3.56 cm, respectively. In addition, antioxidant properties of the samples were measured using total phenolic content and ferric reducing antioxidant power. Their correlations with radioactivity were investigated.

Bazı Seramiklerin Radyasyon Soğurma Kapasitelerinin Belirlenmesi

“…Seramiklerin radyasyon soğurma kapasitelerinin ölçülmesinde Şekil 1'de gösterilen deney düzeneği kullanıldı [1]. Gama ışını kaynağı olarak 370 MBq aktiviteye sahip silindirik bir radyoaktif 241 Am 524 nokta kaynağı kullanıldı.…”

“…İnsanların doğal radyasyona maruz kalmasının ana kaynakları olan doğal olarak oluşan radyonüklitler, özellikle potasyum, uranyum ve toryum serilerinin radyonüklitleridir. Çevresel örneklerdeki doğal radyonüklit konsantrasyonları coğrafi ve jeolojik faktörler nedeniyle çok farklı olabilirler [1].…”