Nonlethal damage

The sequel to acute injury depends on the potency and concentration of the toxic agent and the duration of exposure. Potent gases produce a severe vascular reaction and alveolar flooding. The fluid prevents gaseous exchange, and death of the human or animal ensues. After acute mild nonlethal damage, excess fluid is removed and the resistant Type II cells proliferate and reline the alveoli. The cells subsequently differentiate into Type I cells. 

Some radiation effects result from nonlethal damage to a single cell. These effects are called stochastic. They have the property that there is no threshold for these effects to occur. It is the probability of occurrence rather than its severity which increases with dose. The causation of some cancers may be rooted in a stochastic effect. 

Pain Sensitivity This side effect causes the pain of injuries to be intensified for the user of the drag the more intense the pain, the more debilitating the effects. For every 5 points of damage the user suffers, he suffers ld3 points of nonlethal damage as well. 

In their literature review, Diller and Zante (1982) also identified nonlethal effects from phosgene exposure (lethal effects are described in Section 2.1). Nonlethal information synthesized from this review is presented in Table 1-4. From the above data and from animal data for initial lung damage, Diller and Zante (1982) synthesized information for nonlethal effects of phosgene in humans (Table 1-5). 

Simple experimental approaches to this problem recently started postulate that the repair of clustered DNA damage leads to conversion of nonlethal lesions, e.g., dihydrothymine, or mutagenic lesions, such as 8-OxoGuanine, into lethal double strand breaks. These early experiments have studied kinetics and influence of excision of base lesion within clustered DNA damage by E. coli and nuclear extracts [27,123-129]. 

There is no evidence to argue that the other half result from prenatal environmental effects. But it s reasonable to assume that the prenatal environment in its various forms can be an important factor, and that countless possibilities exist for both lethal and nonlethal effects due to that factor. The simple fact that so many embryos are apparently lost means embryos are particularly vulnerable to damage. 

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