SECTION II.— CHLORIDE OF LIME.
The comparative cheapness of chlorinated lime, and its efficiency as a disinfectant, as shown by extended experiments made under the writer's direction in 1SS5, induced the Committee on Disinfectants to give to this agent the first place among chemical disinfectants.
In the " Conclusions" given in the report of this committee for 1S85, a four per cent, solution is recommended for the destruction of" spore- containing infectious material, " and for excreta. In a foot note, the standard of strength in available chlorine is fixed at '* at least twenty-five per cent."
In the same report (Reports and Papers, A. P. H. A., vol. xi, p. 202) the writer calls attention to the fact that an oxidizing disinfectant is itself destroyed in the reaction to which its disinfecting power is due, and that therefore it is necessary to use such disinfecting agents " in excess of the organic material to be destroyed, otherwise germs included in masses of material not acted upon would be left intact in a fluid which is no longer of any value for their destruction ; and as a few germs may be as potent for mischief as a large number, there would be a complete failure to accomplish the object in view."
Keeping this fact in view, and guided by the experimental data given on pages 199-201 of the report referred to, and by the writer's experi- ments upon normal feces (p. 269), the committee recommended (p. 278)
1 Zeitschrift fiir Hyigene, Bd. iii, Heft. 2, p. 322.
154 REPORT OF COMMITTEE ON DISINFECTANTS.
the use of one quart of a standard solution of chloride of lime containing- four ounces to the gallon for the disinfection of each discharge in typhoid fever, cholera, etc.
In summing up the results obtained in his experiments for the Com- mittee on Disinfectants, Dr. Duggan says, —
The foregoing experiments show that a solution containing .25 of 1 per cent. (1 part to 400) of chlorine, as hypochlorite, is an effective germicide, even when allowed to act only- one or two minutes, while .06 of 1 per cent. (6 parts to 10,000) will kill spores of B. an- thracis and B. subtilis in two hours. A simple calculation will show that all the solutions used were effective when diluted to about this strength, and failed a little below it. No better evidence could be had of the excellent method of Dr. Sternberg for testing agents of this kind. These experiments were all made in duplicate, and they showed a con- cordance which I am satisfied can be obtained by no other method with which I am acquainted.
Notwithstanding the very satisfactory nature of the experimental evi- dence above referred to, I have thought best, in view of the great impor- tance of the subject, to have additional experiments made by an indepen- dent investigator and by a different method. This seemed the more desirable, as some foreign experimenters have reached results which seem not to be in accord with those above referred to. As, however, the amount of available chlorine in the samples of chloride of lime which these investi- gators have employed in their experiments has in no case been stated, it is impossible to compare their results with our own, or to attach any great scientific value to them.
In Koch's experiments, published in the first volume of the Mitthei- lungen aus dem Kaiserlichen Gcsundheitsamte, the statement is made that a five per cent, solution of chloride of lime (value in available chlo- rine not given) failed in two days to destroy the vitality of anthrax spores, but was effective in five days.
Van Ermengem, in his work entitled " Le Microbe du Cholera Asiatiquc (1S85), says, —
Dry chloride of lime, the mixtures of the hypochlorites known under the name of Labarraque's solution, Javelle water, and the sulphate of iron enjoy a reputation which is not sustained by laboratory experiments. A few tests have convinced me that these sub- stances have only a doubtful efficacy for disinfecting the excreta of cholera patients.
Experiment XXV. I have added a notable quantity of a commercial product known under the name of liquid chloride of lime (hypochlorite of soda) to a culture bouillon, before obtaining a complete sterilization of this liquid. Mixtures in the proportion of 1 : 30 have been required to give sterile products.
Dry chloride of lime is scarcely more active when one adds it to a culture in bouillon.
Seitz, in an extended series of experiments upon the bacillus of typhoid fever1 reports a few experiments with this agent. A five per cent, solu- tion was found to destroy vitality in five minutes (p. 39) when a pure culture was used, but a solution of the same strength failed after three days to disinfect typhoid stools. Unfortunately, this author also fails to state the amount of available chlorine present in his solution.
Chloride of lime must be kept in air-tight receptacles, or it soon loses
1 " Bakterialogischen Studien zur Typhus — Aetiologie." Munchen, 1886.
REPORT OF COMMITTEE ON DISINFECTANTS.
155
its value for disinfecting purposes. But, when properly packed, it keeps perfectly well, and as offered for sale in this country I have usually found it to exceed the standard of strength fixed by the Committee on Disin- fectants— 25 per cent. A sample bought a few days since at the nearest drug store was found to contain 34.5 per cent, of available chlorine. It was contained in a pasteboard box, lined with rosin (Rozengrantz patent), and bore the label of C. F. Risley & Co., New York. The package contained four ounces, and cost five cents.
Dr. Bolton's experiments have been made with chloride of lime put up for the medical department of the army in twenty-pound jars, which bear the label of Trubner, Whyland & Co., New York.
TABLE NO. XIX. CHLORIDE OF LIME. RECENT CULTURES IN BOUILLON.3
Organism.
Bacillus of typhoid fever.
Spirillum of Asiatic Cholera.
Friedlander's bacillus, so-called pneumo- coccus.
Bacillus of mouse sep- ticaemia.
Bacillus of foul brood with spores.
Anthrax bacillus, with spores.
Bacillus butrycus, with spores.
Wurzel bacillus, with spores.
Date.
Nov. 11.
Nov. 22.
Nov. 23.
Jan. 25.
1887. Jan. 4.
Jan. 18.
Jan. 25.
1886. Dec. 14.
1887. Feb. 2.
March 10.
March 10.
1886. Dec. 12.
Dec. 14.
March 10. March II.
Amount of Chloride of Lime.
: 100, 1 : 200, Cont. |The amount of avail-
able chlorine in a
5,000, 1:10,000, Cont.! solution of 1 : 2000 is 0.015 per cent.
2,000, 1 : 5,000, Cont.
500, I : 1 ,000, I : 2,000.
50, I : 100, 1 : 200, Cont.
: 2,000, 1 : 5,000, Cont
500, I : 1,000, I : 2,000, Cont.
: 1,000, 1 : 2,000, 1 : 5,000, Cont.
1
1 : 50, 1 : 100, Cont.
: 1,000, 1 : 2,000, 1 : 5,000, Cont.
1 : 50, I : 100, Cont.
1 :5o, 1 : 100.
1 : 50, 1 : 100, Cont.
1 : 100, 1 : 200, 1 : 500, Cont.
I : 50, I : 100, Cont. 1 : 50, 1 : 100.
1:50, 1 : 100, Cont. 1 : 50, 1 : 100.
Colonies in control numberless.
Available chlorine 30 per cent.
Available chlorine 23.75 per cent.
Available chlorine 23.7 5 per cent.
Available chlorine 30"
per cent. Available chlorine 3a
per cent.
Available chlorine 23.75 per cent
Available chlorine 23.75 per cent.
1 The bouillon used in all of Dr. Bolton's peptone-gelatine — without the gelatine.
experiments was prepared exactly as for Koch's flesh-
156 REPORT OF COMMITTEE ON DISINFECTANTS.
TABLE NO. XX.
CHLORIDE OF LIME (AVAILABLE CHLORINE 30 PER CENT.). RECENT CULTURES IN FLESH-PEPTONE-GELATINE, CONTAINING IO PER CENT. OF GELATINE.
Organism.
Date.
Amount of Chloride of Lime.
Remarks.
1886.
Bacillus of typhoid
Dec. 29.
1.: 50, 1 : 100, 1 : 200.
There is a discrep-
fever.
1887.
ancy in the results
Jan. 8.
1 : 100, 1 : 200, 1 : 500, Cont.
obtained in experi- ments of January 13, and in those of
Jan. 13.
1:500, 1:1,000 Cont.
January 8 and Jan- uary 19.
Jan. 19.
1 : 200, I : 500, 1 : 1,000, Cont.
1886.
Anthrax bacillus.
Dec. 15.
1 : 50, 1 : 100, 1 : 200, 1 : 500,
1 : 1,000, Cont.
Eriedlander's bacillus.
Dec. 15.
1 : 50, 1 : 100, 1 : 200, 1 : 500, Cont.
Staphylococcus pyog.
Dec. 30.
1 : 50, 1 : 100, 1 : 200, Cont.
aureus.
Staphylococcus pyog.
Dec. 30.
1:50, 1:100, 1:200,
citreus.
Cont.
Staphylococcus pyog.
Dec. 30.
1 : 50, 1 : loo, 1 : 200, Cont.
albus.
TABLE NO. XXL CHLORIDE OF LIME (AVAILABLE CHLORINE 30 PER CENT.). CULTURES
in bouillon with 10 per cent, of egg albumen added.
Organism.
Bacillus of typhoid fever.
Date.
Dec. 29, 1886. Jan. 6, 1887. April 6.
I : 50, I : 100, I : 200, I : 500, Cont.
1 : 1,000, 1 : 2,000, 1 : 5,000, Cont.
i : 50, 1 : 50, 1 : 100, 1 : 100, 1 : 200, 1 : 200, Cont.
TABLE NO. XXII. CHLORIDE OF LIME (AVAILABLE CHLORINE 28.5 PER CENT.).
Material Disinfected. Date
Typhoid feces (liquid) from a patient in the third week of the disease.
Amount of Chloride of Lime.
1 : 100, 1 : 200, Cont. 1 : 100,1 1:200, Cont. 1 : 50, 1 : 100,2 ] : 200. 1:700,4 Cont.
Remarks.
1 20 colonies in Es- march tube con- taining 1 : 100, none in 1 : 200.
2 Five colonies.
3 Eight colonies.
4 Countless colonies
in control.
REPORT OF COMMITTEE ON DISINFECTANTS. 157
In the above experiments on typhoid feces, as in all other experiments reported, the amount of material to be disinfected has been made equal to the amount of the solution of the disinfecting agent (5 cc. of each)T and the time of exposure has been uniformly two hours. The small number of colonies which developed after the use of a solution of 1 : 100 and 1 : 200 was probably due to the survival of the spores of some com- mon bacillus present in the feces.
In the experiment made Nov. nth, it was noted that when a solution containing 2 per cent, of chloride of lime was used, the presence of a surplus of available chlorine was shown at the end of two hours by the usual test ; 1 when a solution of 1 per cent, was used, there was a slight trace of chlorine at the end of two hours ; when the proportion was reduced to 0.5 per cent., there was no trace of chlorine left. The writer made the following experiment on Dec. 4, 1886, by the method used in the experiments made in 1885. At the same time, Dr. Bolton made a similar experiment with Esmarch tubes.
TABLE NO. XXIII.
BROKEN DOWN BEEF INFUSION, OLD STOCK, AND CHLORIDE OF LIME
(AVAILABLE CHLORINE 30 PER CENT.).
Dr. Sternberg's culture tubes. Esmarch tubes
Amount of Disinfectant.
1 : 50, 1 : 100, 1 : 200, 1 : 50, 1 : 100, 1 : 200. 1 : 50, 1 : 100, 1 : 200, Cont.
The experimental data herein recorded, and the comparative cheap- ness of this agent, fully justify the recommendations made by the com- mittee in their previous report. But the writer would suggest that Standard Solution No. 1 be made by adding six ounces of chloride of lime to the gallon of water (about 4 per cent.) instead of four ounces, as heretofore recommended. This would be 40 grams to the litre.