. Cranberries; : the national cranberry magazine. Cranberries. whether or not hepatomas consti- tute the early stages in malignant tumor formation. Dr. John Higgin- son, director of lARC and well known pathologist and epidemi- ologist, testified that the signifi- cance to man of hepatomas in mice fed DDT is unknown. The fact that some of the strains of mice used for testing carcinogenicity of DDT have a tendency to form hepatomas and the fact that the hepatoma formed cannot be compared to anything found in man makes the use of mice in this type of study of questionable value. For example, at l
. Cranberries; : the national cranberry magazine. Cranberries. whether or not hepatomas consti- tute the early stages in malignant tumor formation. Dr. John Higgin- son, director of lARC and well known pathologist and epidemi- ologist, testified that the signifi- cance to man of hepatomas in mice fed DDT is unknown. The fact that some of the strains of mice used for testing carcinogenicity of DDT have a tendency to form hepatomas and the fact that the hepatoma formed cannot be compared to anything found in man makes the use of mice in this type of study of questionable value. For example, at least two substances which have produced tumors in mice, isonia- zide and penicillin-G, are com- pletely safe for man based on human experience. In addition, results from epidemiological tests are completely negative so far. Extensive epidemiological studies, conducted by the World Health Organization, are now in progress in many countries including the United States, Brazil, Israel, and India. To date no correlation be- tween the levels of DDT found and the prevalence of cancer has been shown. Based on the present know- ledge Dr. Higginson has concluded that there is no evidence that DDT. BOG SANDERS BUILT Also DITCH CLEANERS Richard A. Fielding Route 28 Wareham, Mass. 295-0446 is in any way a carcinogen to man. The human organism contains compounds that are necessary for its existence but if present in too high a concentration are toxic and can even cause death. For example, iodine is necessary for the proper function of the thyroid gland but if present in excessive concentration is definitely poisonous. It is there- fore essential, when evaluating the safety of a chemical, that we consider its dose-response relation- ship with regard to the particular species in question. Man, it appears, is quite tolerant of DDT. In a study by Dr. Way land J. Hayes, ten volunteers were fed DDT up to 200 times the amount they would normally encounter from their every-day intake of food. After
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