Abstract |
The primary objective of the research project was to determine whether arsenite (AsIII), arsenate (AsV), dimethylarsinic (DMA) and monomethylarsonic acid (MA) were initiator carcinogens and/or promoters of DENA-initiated tumors in the rat liver. The maximum tolerated doses (MTD) of the arsenics to be used in this study were determined by treating male Wistar rats in the drinking water increasing concentrations ranging from 10ppm-2560ppm for 7 weeks, depending upon the arsenic studied. To determine whether the arsenic compounds had an initiator or promoter activity, male Wistar rats were partially hepatectomized, treated with a single dose of diethylnitrosamine and on day 7 started treatment with the MTD of each arsenic for 7, 25 and 43 weeks in the drinking water. |