Neutron activation analysis applied to some medical and occupational health studies:Dissertation

The application of neutron activation analysis in five analytical and occupational health studies is illustrated the present work.In all of the five studies the multielement analysis of small size biological samples is performed by neutron activation analysis.The analytical aspects concerning sampling and sample handling prior to neutron activation analysis with particular emphasis on contamination problems will be discussed.Irradiation and the measuring of biological samples in neutron activation analysis involve special aspects which may bear effect on the detection limits of different elements as well as on the precision and accuracy of the analysis.Multielement analyses of human cataractous lenses, of lenses with pseudo-exfoliation, of human cerebrospinal fluid as well as of tissue samples of rats after the rats exposure to stainless steel manual metal arc welding fumes have been carried out.Se, Cr, Ni, Sc, Rb, Fe, Zn and Co could be detected in human lenses, Na, K, Cl, Fe, Co, Zn, Se, Rb and Ag in human cerebrospinal fluid and Cr, Ni, Fe, Zn, Se, Rb and Co in organ samples of rats.The differences of element concentrations both in cataractous lenses as well as in pseudo-exfoliative lenses are looked into.In the application of activation analysis to the study of cerebrospinal fluid the principal emphasis was laid on the risk of contamination during sampling and the problems when analyzing small amounts of samples with low element concentrations.The retention kinetics of Cr, Ni and magnetic Fe into different organs of exposed rats yield knowledge on the welding of stainless steel as an occupational health problem.Neutron activation analysis is a suitable multielement analytical method when the samples are liable to be contaminated, when the sample size is small and furthermore, when the element concentrations are low.However, the analysis of biological samples of different kinds will call for special attention during all stages of the analytical procedure so as to ensure the reliability of the analytical results