| Popis: |
In order to determine the toxic effects of a compound administered by the inhalation route it is frequently necessary to employ exposure periods of long duration. It is of interest, therefore, to establish whether or not an inverse relationship exists between exposure time and the concentration of the test compound. Here some preliminary data on the toxicity of carbon tetrachloride when administered to rats via the inhalation route is presented. Exposure of the rats was performed with whole body equipment and the concentration of carbon tetrachloride (CCl4) in the air stream was routinely monitored. The rats were exposed once on each of 5 consecutive days. Blood samples were taken at the end of this period and the haematological and blood chemistry parameters were analysed. Samples of lung, trachea, stomach, liver, and kidney were processed for histopathological evaluation. The results of the biochemical analyses (see Table) indicated that the toxicity was a function of the total concentration of CCl4 absorbed. These data suggest that a threshold exists at the highest doses administered during the shortest exposure time, resulting in a decrease in toxicity. |
