. Cranberries; : the national cranberry magazine. Cranberries. DDT Continued from Page 10 been tested in a great number of experiments with mice, rats, ham- sters, and dogs. Although in the vast majority of cases negative results have been obtained the interest, of course, is in those experiments that suggest that the pesticide might have some carcino- genic properties. A study by Fitzhugh and Nelson (1947) of the Food and Drug Administration on rats fed DDT for two years gave the first hint of possible carcinogenic properties. The authors described the treated rats as having a tendency toward
. Cranberries; : the national cranberry magazine. Cranberries. DDT Continued from Page 10 been tested in a great number of experiments with mice, rats, ham- sters, and dogs. Although in the vast majority of cases negative results have been obtained the interest, of course, is in those experiments that suggest that the pesticide might have some carcino- genic properties. A study by Fitzhugh and Nelson (1947) of the Food and Drug Administration on rats fed DDT for two years gave the first hint of possible carcinogenic properties. The authors described the treated rats as having a tendency toward hepatocarcinogenisis (formation of liver tumors). They felf that the liver tumors found could be re- garded as low grade hepatic cell carcinomas. Their dlDservations, however, have been criticised be- cause it was shown in their paper that the DDT effects on the liver were reversible. It is now well known that the effects of carcin- ogens on target tissues leading to tumor formation are irreversible. At a later time when the above study was reviewed along with many others by Lehman (at that time Director of the Division of Pharma- cology, Bureau of Scientific Re- search, Food and Drug Administration) he concluded simply by saying: "DDT is not a ; To be fair with the Fitzhugh and Nelson study, it was not known at the time of their work that the changes produced by DDT in the liver were not charac- teristic of DDT alone but similar if not identical to those produced by phenobarbital, the botanical insecti- cide pyrethrum, and a number of other compounds. The changes in the liver produced by these com- pounds primarily involve the endo- plasmic reticulum for formation of microsomal enzymes. These changes are now known to be reversible. By far the study that has created the greatest furor concerning DDT and cancer is that performed by the Bionetics Research Laboratories (BRL) for the National Cancer Institute-published in 1969. This was a broad study of the ca
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