Deuterium

The international electromagnetic field (EMF) project of the World Health Organization (WHO) is a collaborative effort of the WHO teams for Environment, Climate Change and Health (ECCH) and Radiation and Health (ionizing and non-ionizing). The purpose of the effort is twofold. Firstly it seeks to create and house a database of legislation pertaining to EMF exposure. Secondly, it seeks to promote dialogue on the risks related to EMF exposure.


The establishment of the EMF Project is motivated by the fact that EMF of a very broad range of frequencies represents one of the most common and fastest growing environmental influences on human health. EMF may have notable positive or negative effects on health, depending on the exposure context. EMF has been around since the birth of the universe, with light being its most familiar form. Electric and magnetic fields are part of the spectrum of electromagnetic radiation, which extends from static electric and magnetic fields, through radiofrequency, ultraviolet, and infrared radiation, to X-rays.


Various Organs of State have reviewed the research endeavors of the NRF in this emerging field and found that the research is innovative and strongly aligned with South Africa’s national interests. The EMF project is a multidisciplinary research endeavor integrating efforts from multiple sectors. Of particular import to South Africa is research into EMF exposure risks, EMF shielding modifications, and bio-adaptation mitigation options related to climate change. The EMF Project is endorsed by the Surgeon General, and the Nation’s doctor is provided with the best available scientific information on how to improve health outcomes and reduce the risk of illness and injury. The mission of the EMF Project is to protect, promote, and advance the health of our Nation.

Assessing hydration, that is, total body water (TBW) in adolescent athletes should be part of a comprehensive training program. However, there are no specific methods to assess TBW in young athletes. Moreover, the use of traditional techniques developed in healthy youths, based on a 2-compartment model, may yield inaccurate TBW estimates in young athletes. Therefore, the purpose of this study was to assess the accuracy of TBW non-reference field methods with a criterion method (i.e., deuterium dilution) in 118 adolescent athletes. Body volume was assessed by air displacement plethysmography, bone mineral was measured by dual-energy X-ray absorptiometry, and TBW by deuterium dilution. Non-reference TBW methods included 2 bioelectrical impedance analysis techniques (Tanita Body Composition Analyzer, model TBF-310) and bioelectrical impedance spectroscopy (BIS) (model 4000B); the Lohman's hydration constants of fat-free mass (FFM); and 3 derived anthropometric equations developed, respectively, by Kushner et al., Wells et al., and Morgenstern et al. The highest accuracy between TBW estimates and the reference model in both girls and boys was observed using the Lohman's constants (r2= 0.94, SEE = 1.56 kg; r2 = 0.92, SEE = 2.42 kg, respectively; p < 0.001), followed by both foot-to-foot Tanita (r2 = 0.88, SEE = 2.15 kg; r2 = 0.87, SEE = 3.01 kg, respectively; p < 0.001) and BIS (r2 = 0.92, SEE = 1.70 kg; r2 = 0.87, SEE = 3.04 kg, respectively; p < 0.001) with slopes and intercepts not significantly different from the line of identity. The regressions between anthropometric equations and the criterion method deviated from the line of identity (p < 0.05). The practical application of this study is that the specific constants of FFM hydration developed by Lohman seem to accurately estimate TBW in adolescent athletes. Foot-to-foot Tanita and BIS were also found to be valid and non-biased tools for predicting TBW. It would appear that the 3 anthropometric equations used are not appropriate for young athletes.

Prompt gamma-ray neutron activation analysis (PGNAA) is a nuclear analytical technique for the determination of trace and other elements in solid, liquid or gaseous samples. The method consists in observing gamma rays emitted by a sample during neutron irradiation. The PGNAA system was built using a moderated and shielded deuterium–deuterium (D–D) neutron generator. This facility has been developed to determine the chemical composition of materials. The neutron generator is composed of three major components: An RF-Induction Ion Source, the Secondary Electron Shroud, and the Diode Accelerator Structure and Target. The generator produces monoenergetic neutrons (2.5 MeV) with a yield of 1010 n/s using 25–50 mA of beam current and 125 kV of  acceleration voltage. Prompt c-ray neutron activation analysis of 10B concentrations in Si and SiO2 matrices was carried out using a germanium detector (HPGe) and the results obtained are compared with a PGNAA system using a NaI detector. Neutron flux and energy distribution from D–D neutron generator at the sample position was calculated using Monte Carlo simulation. The interaction properties of neutrons in a Germanium detector have been studied.