Dynamics of deuterium turnover in the human body using 2(1)D(gamma, n) reaction

A rapid non-destructive and sensitive technique is used by which total body water and its rate of turnover (excretion) in human subjects can be easily measured. Subsequently, a simple calculation is made in estimating the total body fat and lean body mass. The measurements are, therefore, expected to shed useful light on the measurement technique as well as on the movement of body water in humans, and this will glean an understanding of physiological laws governing such movements. The method employs the activation of deuterium in water by bremsstrahlung radiations which are produced by stopping 3 MeV electrons in a gold target. The detection of photoneutrons, so obtained in the reaction 2(1)D(gamma, n), is accomplished by the capture of fission fragments in Solid State Nuclear Track Detector (SSNTD) issuing from the 235U(n, f) reaction. These fission events are then automatically counted by a spark counter. Thermal neutrons, required for the 235U fissioning, are obtained by employing a graphite moderator assembly at the core of which water and urine samples are being irradiated. The development of a few basic measurement parameters and their utilization in such measurements are also reported in the paper.