NUMEROUS authors123 have described the toxic effects observed in different species of warm-blooded animals exposed to DDT — 2,2 bis (p-chlorophenyl)-l, 1,1-trichlorethane — in various ways. By and large, clinical4 and pathological5 studies of these animals revealed that the principal action of DDT was on the central nervous system and liver.The general consensus is that, used with reasonable care, preparations containing DDT do not present significant toxic hazards to human beings. Case,6 however, reported toxic effects of a 2 per cent solution of DDT on 2 men exposed for forty-eight hours under special conditions, consisting of an oily surface, . . .