PRINCIPAL INVESTIGATOR (S ) 



Cornelius A. Tobias, Tracy C. H. Yang, M. 

 Freeling, S. Fogel, Horst Buecker, M. Delpoux, E. 

 H. Graul, G. Horneck, A. R. Kranz, H. Planel, W. 

 Ruether, U. Scheidemann, C.Thomas, B. Toth, 0. C. 

 Allkofer, R. Beaujean, E. V. Benton, W. Enge, R. 

 Facius, H. Francois, W. Heinrich, D. Hildebrand, 



C. Jacquot, R. Kaiser, J. P. Massue, E. Obst, D. 



D. Peterson, R. Pfohl, G. Portal, G. Reitz, E. 

 Schopper, M. Schaeffer, J. U. Schott, and G. 

 Siegmon 



EXPERIMENT TITLE/NUMBER : BIOSTACK III 



PROGRAM/MISSION : Apollo-Soyuz Test Project 



CLASSIFICATION : Plant - Corn seeds ( Zea mavs ) 



DISCIPLINE(S) : Radiobiology , Cell biology, Behavioral science 



OBJECTIVES : To study the influence of HZE particles on growth, differen- 

 tiation and morphogenesis, and mutation induction. 



PROTOCOL : The BIOSTACK flight experiment was stored in the R-1 compartment on 

 the Apollo capsule where there was the least shielding from ambient radiation. 

 The specimens were arranged in monolayers, imbedded in polyvinyl alcohol, and 

 stacked between track detector sheets. Particle tracks were located in 

 relation to biological objects and the physical quantities of these particles 

 were determined. 



EQUIPMENT : Two cylindrical aluminum containers which each enclosed a stack of 

 biological specimens and dosimeters. 



RESULTS : Growth and development of some seeds hit by HZE was retarded, but it 

 was not significant. Results are incomplete. Of 160 seeds, 90 were hit. 



CONCLUSIONS : HZE-particle-induced damage might become manifest if nonreplace- 

 able cells are destroyed. In manned space flight, the primary concern would 

 be the nervous system. However, the risk to man from HZE particles during 

 space flight can be sufficiently lowered if the maximum possible shielding 

 against HZE particle bombardment is ensured in the design and construction of 

 future space vehicles. 



PUBLICATIONS : 2b, 39, 116, 121, 122, 124, 185, 186, 188, 212, 419, 420 



153 



