抄録
The author has already informed in the previous report, that the rabbit poisoned by the inhalation of carbon disulphide gas dies without fail by the paralysis of the respiratory centre. This report is based on the results obtained from the research with regard to the determination of the minimal lethal dose in the case of very acute intoxication by the inhalation of evaporated carbon disulphide gas. The experimental method is as follows:
10c.c. that is about 12.7g. of carbon disulphide is put in a small gas washing bottle, which has a capacity of about 100c.c. and is weighing about 80g. The bottle is weighed immediately after the two openings of it are corked closely by means of gum hat. The expiratory opening of the bottle is then connected with the inspiratory opening of the tracheal tube, which is inserted into the trachea of rabbit. Thus the evaporated gas of carbon disulphide in the bottle, together with the air passing through this liquid, is allowed to enter the lung of the animal, which will consequently be poisoned at once. When the respiration of the poisoned animal is ceased, the bottle is quickly taken off from the connection, thereupon the two openings being corked with the gum hat, and is weighed. The difference between the two weights is the total dose, evaporated in the bottle and mixed with the inspired air.
Four of the same gas washing bottle, each of them containing 30c.c. of 10% caustic kali alcoholic solution, are connected with each other by means of gum tube. The inspiratory opening of these bottles on one end is connected with the expiratory opening of the tracheal tube, inserted into the trachea of the animal, and the expiratory opening on the other end is also connected witd a large bottle containing about five litres of water, which flows out in the constant pressure. In this way a negative pressure arises in this large bottle, and it induces the expired air of animal into the latter through the caustic kali alcoholic solution contained in the four gas washing bottles.
The carbon disulphide, while passing through the caustic kali alcoholic solution together with the expired air, is changed into kali xanthogenate and is dissolved in this solution, thereby only the air gets off from it and comes into the large water bottle. The quantity of the kali xanthogenate to be found in the four gas washing bottles is calculated by means of 1/20 normal cupper sulphate solution. The calculated quantity is then substituted from the total quantity consumed as above mentioned, and the remaining corresponds to the absorbed quantity in she blood of animal, that means the minimal lethal dose.
As the water in the large bottle is kept at about the same temperature as that of the experimental chamber, and flows out in the constant pressure so as to make a negative pressure in this bottle as well as in the four connected gas washing bottles, thus inducing the expired air containing carbon disulphide into the bottles, so the volume of the water flowing out from the large bottle corresponds on the whole to the volume of the air (except the carbon disulphide gas contained in it.) inspired by the animal. It has been found by calculation that the quantity of poisonous gas in the inspired air averages about 17vol.%.
From the experiments on nineteen cases the author came to the following results:
The total quantity of the carbon disulphide evaporated in the bottle and mixed in the inspired air of the animal amounts to about 1g. on an average, of which about the half (0.5g.), that is 0.3g. for 1 kilogram of bodily weight, is absorbed into the blood of the animal. This is the real minimal lethal dose pro kilogram of bodily weight in the case of very acute intoxication in the rabbit by the inhalation of carbon disulphide gas. And the animal, inspiring the air which contains about 17vol.% of carbon disulphide dies in only 4 minutes on an average owing to intoxication.
