nanifest only in futuf,'e generations. They are caused by rad,iatiOn-induced changes i.n the gonad ce1ls. These defects nidht consist of lovered fertility, spontaneous abortion, stillborn children, children born vith ma]formations or nonspecific constitutional ve€.knesses, To assess any precise xelationship betveen ladiation doses and frequencies of genetic dsmage is difficuLt. It is, hovever, bel-ieved to be of about the same order of roagnitude as that of rad iation-induc ed. cancsl.. According to ICRP, the total- risk for serious genetic defects is estimated. at one case in l-o,ooo nanrad. About haJ-f of these defects will show up in the first two generations following the irrad.iated parents. \5, The preceding discussions have, in essence, been restricted to one effect at a time, and interactions of various effects have ].argely been disregarded' Such interactions will occur, howeve? r end generally speaking they ale expected to be synergic, which means that a conbination of weapons effects vi1l produce a more severe result than the sum of the injuries or darnage caused by each single effect. )+5. For study pr.rrposes, ir,rnerli at e casualties fron a nuclear explosion can be treated. as caused by one dominating effect - 1.e,, the one having the l-argest lethai radlus with respect to yield, height-of-burst , degree of protection, etc. rn every situation, ho'wever, there 1"Ii11 be a zone where one effect by itsel-f ltould not cause large numbers of fatalities but lrhere many peopl-e night stil1 succrmb due to a co!0bination of injuries. rhis vas observed in hurnans after the l-945 bonbings in Japan" and later animal experiments have contributed. to the und.erstand.in8 of the biological mechanisms involved.. These are related to the depletion, caused' by ionizing radiation, of certain corpuscl-es in the blood which produces a state of
**Analysis**
The text appears to be discussing the effects of radiation on human health, specifically the genetic defects caused by radiation-induced changes in gonad cells. The text also touches on the concept of synergic interactions between different effects of radiation, which could lead to more severe consequences. The language used is technical and scientific, suggesting a focus on scientific research rather than practical applications.

**Category**
Health, Science and technology