Body Potassium Content and Radiation Dose from ⁴⁰K for the Urals Population (Russia)

<div><p>Long-term whole-body monitoring of radionuclides in residents of the Urals Region has been performed at the Urals Research Center for Radiation Medicine (URCRM, Chelyabinsk). Quantification of ⁴⁰K was achieved by measuring the ⁴⁰K photopeak with four phoswich detectors in whole body counter SICH-9.1M. The current study presents the results of ⁴⁰K measurements in 3,651 women and 1,961 <i>t</i>-test; <i>U</i>-test men aged 11–90; measurements were performed in 2006–2014. The residents belonged to two ethnic groups, Turkic (Tatar, Bashkir) and Slavs (mainly Russian). The levels of ⁴⁰K-body contents depend upon gender, age, and body mass. Significant ethnic-differences were not found in ⁴⁰K-body contents and ⁴⁰K concentrations in terms of Bq per kg of body weight (in groups homogenous by age and gender). Both ⁴⁰K-body contents and concentrations were significantly higher in men than in women in all age-groups; the difference was about 25%. The measured ⁴⁰K-body content in men of 20–50 years was about 4200 Bq (134 g of K) and about 3000 Bq (95 g of K) in women. By the age of 80 these values decreased to 3200 Bq (102 g of K) in men and 2500 Bq (80 g of K) in women. Annual dose rates were maximal in the age group of 20–30 years– 0.16 mGy/y for men and 0.13 mGy/y for women. Further, the dose-rates decreased with age and in the groups of 60–80 years were 0.13 mGy/y for men and 0.10 mGy/y for women. Within groups homogeneous by age and gender, individual dose rates are described by a normal statistical distribution. The coefficient of variation ranges from 9 to 14%, and on the average is 12.5%. Doses from naturally occurring ⁴⁰K accumulated over 70 years were found to be 9.9 mGy for men and 8.3 mGy for women; over 90 years - 12.5 and 10.4 mGy.</p></div

Anthropometric characteristic of persons under study.

<p>Anthropometric characteristic of persons under study.</p

Characteristics of annual dose rates for Urals residents depending on gender and age.

<p>Characteristics of annual dose rates for Urals residents depending on gender and age.</p

Characteristics of phantoms, DF-values and dose coefficients for ⁴⁰K derived from [12].

<p>Characteristics of phantoms, DF-values and dose coefficients for ⁴⁰K derived from [<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0154266#pone.0154266.ref012" target="_blank">12</a>].</p

Parameters of multiple regressions for two independent variables (age, BMI) which predict specific activity of ⁴⁰K.

<p>Parameters of multiple regressions for two independent variables (age, BMI) which predict specific activity of ⁴⁰K.</p

Dependence of dose coefficient on body weight.

<p>Dependence of dose coefficient on body weight.</p

Comparison of the results of ⁴⁰K measurements for adult persons with published data.

<p>Comparison of the results of ⁴⁰K measurements for adult persons with published data.</p