Asher J. Finkel

THE CANCER HAZARDS OF INDUSTRIAL AND ACCIDENTAL EXPOSURE TO RADIOACTIVE ISOTOPES

Data are reviewed from studies carried out during the past 27 years on the toxicity of Ra, the incidence of lung cancer in uranium miners, and animal studies on the induction of tumors by inhaled or ingested radioactive materials. The relation between body content and tumor induction in man is discussed. It is pointed out that the sites of tumors induced by Ra are related to the sites of deposition in the skeleton and physical factors concerned with the decay of Ra and Rn in the body. Finally, data on Ra dial painters and U miners constitute all the data available on hazards to man from industrial and accidental exposure to radioactive isotopes.

THE EFFECT OF DEUTERIUM OXIDE ON ASCITES TUMOR GROWTH IN MICE

The growth of Krebs-2A ascites tumors in mice was appreciably depressed by the presence of deuterium in the body fluids in concentrations ranging from 13 to 32%. Measurement of the glutamic oxalacetic transaminase (GO-T) levels revealed that with increasing deuteration there was a prcgressive elevation of serum GO-T in tumor-bearing mice and an even more rapid rise of ascitic plasma GO- T. These data suggest that deuteration of the organism leads to tumor-cell injury with resulting release of GO-T into the ascitic fiuid, whence it is carried into the general circulation. The notion that deuterium injures and possibly destroys mouse ascites tumor cells is supported, in part, by the terminal increase in the incidence of eosin-stainable tumor cells and, in part, by the absence of any striking difference in mitotic index of deuterated and nondeuterated tumor cells. These conclusions also apply to transplantable mouse ascites tumors. (auth)

Radium retention in mice after single intravenous injection.

The retention of intravenously injected radium was studied in mice by means of whole-body 7-ray spectroscopy in order to acquire some understanding of the radium retention pattern in a laboratory mammal. This study was done with the hope that such information could eventually be applied to the interpretation of data acquired in our studies with human patients who ingested or were injected with radium thirty to forty years ago. In particular, we were interested in the validity of the power function proposed by Norris et al. (1) as a description of radium retention after intravenous injection and in the possibilities of extrapolating from mouse data to the human situation. We were also interested in evaluating the pattern of retention of radon daughters with time and in ascertaining whether the situation in mice paralleled that found by Mays et al. (2) for rats, dogs, and man. Radium-226 and the radon daughters present in small animals can be determined repeatedly by external y-ray spectroscopy without injury to the animal. The retained radon, which does not emit 7-rays, is determined by quantitative measurement of its short-lived daughters, RaB(Pb214) and RaC(Bi214), by a refinement of a method proposed by Gustafson and Marinelli (3). The Ra226 content is determined by stripping the RaB and RaC spectra from the gross y-ray spectrum of the animal. This method is limited to small animals and to small biological specimens where absorption and scattering of the y-rays within the test object are minimal. This paper deals with an intensive study of four young adult female mice after each had received an intravenous injection of Ra226 bromide. Preliminary findings (4) encouraged us to pursue these studies further and to apply electronic computer techniques in the analyses of the data. The results obtained, which are presented here, formed the basis for subsequent investigations dealing with other aspects of radium metabolism in the mouse and in man, which will be described in forthcoming reports. METHODS

137Cesium retention in mice of different ages.

Summary Analysis of the retention data of mice of various ages demonstrated that after intravenous injection the retention of 137Cs chloride varied as a function both of the age of the animal at the time of injection and of the time since injection. The effective retention of cesium was lowest in the youngest mice, progressively higher for the older mice and then somewhat lower again for very old mice. Moreover, the retention does not change in a uniform manner that can be described by the sum of a series of exponential terms. If the retention is to be described accurately, it is frequently necessary to use a series of discontinuous exponential terms, each of which describes the retention over a limited time span.

Effect of adrenocorticotrophic hormone on tissue distribution and acute toxicity of beryllium

Summary Adrenocorticotrophic hormone (ACTH) had no appreciable effect on the distribution or retention of radioberyllium, injected into mice with and without carrier beryllium sulfate. The survival of mice acutely poisoned with beryllium sulfate was not influenced by ACTH.

Salicylates and Experimental Beryllium Poisoning.

Summary Intravenously or intraperiton-eally administered sodium salicylate in dose levels of 600 mg per kg is an effective antidote for acute beryllium poisoning in mice when given up to 8 hours after the administration of intravenous beryllium sulfate in LD95 amounts. Salicylate analogues without the ortho-hydroxy, carboxylic acid grouping were generally ineffective as were 2 dihydroxyben-zoates.