The second part of this paper concerns whole body autoradiography and results obtained
similar to those reported in the first paper. Both (14)C-DDT and (14)C-Dieldrin were taken up by all tissues 12 hours after their oral administration with high concentrations in fat tissues, next in liver and kidneys. Deposition in fat tissues increased gradually and then decreased gradually, but even after 5 days, these compounds were found in all tissues, especially more in fat tissues. Another interesting point is that these chemicals were also taken up by the bone marrow. Therefore, hypoplastic anemia or other blood dyscrasias may have something to do with this observation. These results suggest that once being taken up, organo-chlorine pesticides remain in animal tissues for a prolonged period of time, and the repeated, excessive exposure to them may, prodce chronic poisoning or various deleterious effects on human bodies.