Radionuclides Transfer from Soil to Tea Leaves and Estimation of Committed Effective Dose to the Bangladesh Populace

Abstract

Considering the probable health risks due to radioactivity input via drinking tea, the concentrations of 226Ra, 232Th,40K and 137Cs radionuclides in the soil and the corresponding tea leaves of a large tea plantation were measured using high purity germanium (HPGe) γ-ray spectrometry. Different layers of soil and fresh tea leaf samples were collected from the Udalia Tea Estate (UTE) in the Fatickchari area of Chittagong, Bangladesh. The mean concentrations (in Bq/kg) of radionuclides in the studied soil samples were found to be 34 ± 9 to 45 ± 3 for 226Ra, 50 ± 13 to 63 ± 5 for 232Th, 245 ± 30 to 635 ± 35 for 40K and 3 ± 1 to 10 ± 1 for 137Cs, while the respective values in the corresponding tea leaf samples were 3.6 ± 0.7 to 5.7 ± 1.0, 2.4 ± 0.5 to 5.8 ± 0.9, 132 ± 25 to 258 ± 29 and <0.4. The mean transfer factors for 226Ra, 232Th and 40K from soil to tea leaves were calculated to be 0.12, 0.08 and 0.46, respectively, the complete range being 1.1 × 10−2 to 1.0, in accordance with IAEA values. Additionally, the most popularly consumed tea brands available in the Bangladeshi market were also analyzed and, with the exception of 40K, were found to have similar concentrations to the fresh tea leaves collected from the UTE. The committed effective dose via the consumption of tea was estimated to be low in comparison with the United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR) reference ingestion dose limit of 290 μSv/y. Current indicative tea consumption of 4 g/day/person shows an insignificant radiological risk to public health, while cumulative dietary exposures may not be entirely negligible, because the UNSCEAR reference dose limit is derived from total dietary exposures. This study suggests a periodic monitoring of radiation levels in tea leaves in seeking to ensure the safety of human health.

Radıometrıc Measurements in of Ladybird (Berberis Thunbergii), Bowood (Buxus Sempervirens Rotundifolia) and Gold Tassel (Euonymus Japonica Var. Aurea) Under Cadmıum and Zınc Stress

“…Potassium has an important role in photosynthesis, translocation of starches and sugars, plant-water relations, protein synthesis, activation of plant enzymes, resistance to plant diseases [8,29]. Similar results were reported in the studies examining the herbaceous and woody plants [7,15,27]. Manigandan et al [3] reported the 40K activity concentration in some plant species grown in rain forests of India to vary between 160.4 ± 12.3 and 206.4 ± 13.4 Bq kg -1 and TF value to vary between 0.802 and 0.954.…”

“…[32] analyzing 45 wheat flour samples reported 232Th activity concentration values that were much lower than in the present study. Similarly, Absar et al [27] reported the 232Th activity concentration of tea plant leaves to be 2.4 ±0.5-5.8 ±0.9 Bq kg -1 and that of soil to be 50±13-63±5 Bq kg -1 , whereas TF (232Th) was found to be 0.05±0.04. Bilgici Cengic & Çağlar [20] analyzed various herbs widely used in the Eastern Anatolian region and reported the 232Th activity concentration to be 55.99±4.32 Bq kg -1 and TF value to be 0.88.…”

“…15 (0-5 cm: 61-280 Bqkg -1 ; 10-15 cm: 14-224 Bq kg -1 ). But Absar et al [27] reported the 232Th, 40K, and 137Cs activity concentrations in soil to be in the ranges of 50 ±19-65± 21, 245 ±30-635 ±35, and 137Cs 3±1-9±1, respectively. In the present study, 232Th and 137Cs values were lower than those values but 40K was found to be in a similar range.…”

Study of Natural Radionuclides in Frequently Consumed Foodstuffs in Ode-Irele, Ondo State, Nigeria

“…Van et al (2019) compared the Annual Committed Effective Dose Rate (ACED) of foodstuffs consumed by the people of Red River Delta in Vietnam to the ACED of other countries and concluded that the foodstuffs in Vietnam are safe for consumption because the ACEDs estimated for all the NORMs were found to be below the Global Limit of 1 mSv/yr. Absar et al (2021) examine tea leaves' naturally occurring radioactive elements using a Gamma-ray spectrometer.…”

Transfer Factors of Natural Radionuclides from Soil to Medicinal Plants used by Local People in Eastern Anatolia, Turkey

“…In some studies, the concentration of natural radioactivity and associated effective dose levels for 226 Ra, 232 Th, 40 K and 137 Cs radioisotopes were measured on agricultural lands, fertilizers and plant samples (grain crops, vegetables, medicinal plants and etc.) from different countries in the world (Al-Hamarneh et al, 2016;Bilgici Cengiz and Çağlar, 2019;Jibiri, and Fasae, 2012;Uchida and Tagami, 2007;Asaduzzaman et al, 2014;Absar et al, 2021;Bilgici Cengiz, 2019;Alfred et al, 2014).…”