An analysis of the literature shows a lack of data about basic biological parameters regarding cytogenetic dosimetry as applied to neutron fields, in the dose range below 50 rad. Human peripheral blood lymphocytes were exposed in vitro to a degraded fission neutron spectrum of mean energy 0.4 MeV. The dose-range was 0.2--50 rad delivered at a dose-rate of about 0.2 or 7 rad/min. The results were processed using a computer programme. Both experimental data for dicentric induction, and theoretical considerations indicate the first-order polynomial as the best fitting dose--response function. The implications of these results for cytogenetic dosimetry are discussed. A comparison with 250 kV X-ray data in the same range gives an r.b.e. of 18.5 +/- 3.1.
Chromosome Aberrations Dose-Response Relationship, Radiation